WO2023281599A1

WO2023281599A1 - Treatment apparatus

Info

Publication number: WO2023281599A1
Application number: PCT/JP2021/025348
Authority: WO
Inventors: 邦生桑原; 雄一大森; 悠暉豊田
Original assignee: 日本ライフライン株式会社
Priority date: 2021-07-05
Filing date: 2021-07-05
Publication date: 2023-01-12
Also published as: JPWO2023281599A1; JP2023008909A

Abstract

The treatment apparatus according to one embodiment of the present invention comprises: a catheter having a shaft extending along the axial direction; a stent graft configured to include a stent and an additional structure part, the stent graft having a first region and a second region, wherein the first region includes only the stent disposed therein along the axial direction, and the second region includes at least the additional structure part disposed therein; and a cover for keeping the stent in the first region in a diameter-contracted state in a direction in which, in the tip end region of the shaft, the first region is positioned on the tip end side of the shaft, and the second region is positioned on the base end side of the shaft. The cover has: a cylindrical outer layer part that is positioned on the outer peripheral side of the shaft; an inner layer part that is positioned on the inner peripheral side of the shaft and extends through the inside of the shaft to the base end side of the catheter; and a turn-back part that connects the outer layer part and the inner layer part on the tip end side of the shaft. The stent is kept between the outer layer part and the shaft in the diameter-contracted state.

Description

therapy equipment

The present invention relates to a treatment device used for treatment of, for example, arterial dissection (dissecting aneurysm).

In recent years, when stenosis or occlusion occurs in blood vessels or other tubular organs in the body, or when dissecting aneurysms occur in blood vessels, stents made of wires (elemental wires) are placed in the affected area. Thus, a method (stent placement) is used to expand and maintain the lumen of a tubular organ and prevent rupture of an aneurysm or the like. In particular, stent-grafts, which are provided with tubular grafts covering such stents, are used, for example, in the treatment of arterial dissection in blood vessels.

By the way, recently, the OSG (Open Stent Graft) method has been proposed as one of the treatment methods for arterial dissection in the thoracic aorta. In this OSG method, the aorta is incised after thoracotomy, a stent graft is inserted through the incision, and the proximal end of the stent graft and the patient's blood vessel are anastomosed by suturing. is designed to anastomose another artificial blood vessel to this anastomosis.

In addition, in a procedure using such an OSG method, a delivery catheter as disclosed in Patent Document 1, for example, is used. This catheter is adapted to mount (hold) a stent-graft whose diameter is reduced when the stent-graft is inserted through the above-described incision.

Japanese Patent No. 6718455

By the way, treatment devices such as catheters for delivery are generally required to improve convenience during treatment. Therefore, a proposal that can improve the convenience of such treatment is desired.

It is desirable to provide a treatment device that can improve convenience during treatment.

A therapeutic device according to one embodiment of the present invention includes a catheter having a shaft extending along the axial direction, a stent, and an additional structure. and a second region where at least an additional structure is arranged; and a distal region of the shaft in which the first region is located distally of the shaft and the second region is located on the distal side of the shaft. a cover for holding the stent in the first region in a reduced diameter condition with the shaft oriented proximally of the shaft. The cover includes a cylindrical outer layer located on the outer peripheral side of the shaft, an inner layer located on the inner peripheral side of the shaft and extending to the proximal side of the catheter through the shaft, and the shaft. and a folded portion connecting the outer layer portion and the inner layer portion on the distal end side. A stent is held in a reduced diameter state between the outer layer and the shaft.

In the therapeutic device according to one embodiment of the present invention, the outer layer portion, the inner layer portion, and the folded portion are provided in the cover, respectively, and the stent in the first region of the stent graft is: It is held in a reduced diameter state between the outer layer portion and the shaft. As a result, when the diameter-reduced stent is expanded from within the cover by pulling the proximal side of the inner layer portion of the cover toward the proximal direction of the catheter (pulling operation), the diameter is expanded as follows. Become. That is, the outer layer of the cover is pulled into the shaft through the folded portion and gradually pulled toward the proximal end of the catheter, so that the stent in a reduced diameter state is gradually expanded from within the cover by its self-expanding force. It will expand and expand in diameter. Therefore, for example, a stent graft (such as a stent) having a reduced diameter is placed between the inner layer of the cover and the shaft, and the proximal end of the outer layer of the cover is pulled (comparative example). different, as follows: That is, when the stent in a diameter-reduced state is deployed from within the cover by a pulling operation, the additional structural portion positioned on the proximal side (the second region) of the stent is operated on the proximal side (proximal side). is avoided.

In the treatment apparatus according to one embodiment of the present invention, a pull tube extending from the vicinity of the distal end of the catheter to the proximal end along the axial direction is further provided, and the distal end of the pull tube is provided with the reduced diameter state. A pusher may be provided to abut against the stent on the distal end side of the stent. In this case, when deploying the reduced-diameter stent from within the cover, the pull tube is pulled toward the proximal end of the catheter along with the operation of pulling the inner layer portion of the cover toward the proximal end. So, it becomes as follows. That is, since the diameter-reduced stent is pushed toward the proximal end of the shaft by the plunger, it is deployed from within the cover and expanded in diameter, so that the distal end (distal end) of the stent moves toward the proximal end. The stent is deployed from the proximal side while moving gradually. Therefore, when the stent graft is left in the patient's body, the jumping phenomenon of the stent (movement of rapidly shortening toward the base end when deployed) is suppressed, resulting in further improvement of convenience during treatment. will do.

In this case, the pull tube is pulled in the proximal direction of the catheter after the first pulling operation is started, which is the operation of pulling the proximal side of the inner layer of the cover in the proximal direction of the catheter. By performing the second pulling operation, the diameter-reduced stent is expanded from within the cover while being pushed toward the proximal end of the shaft by the plunger. may In this case, when the second pulling operation is started after the first pulling operation is started, jumping of the stent occurs as described above when the stent graft is left in the patient's body. This will prevent the phenomenon from occurring.

Furthermore, in this case, a marker may be provided in the base end region of the inner layer of the cover to indicate the start timing of the second pulling operation after the start of the first pulling operation. In this case, the marker can be used by the operator to easily grasp the approximate start timing of the second pulling operation after the start of the first pulling operation. As a result, convenience in treatment is further improved.

In addition, in the treatment apparatus according to one embodiment of the present invention, the additional structural section includes, for example, a tubular graft and a cuff section disposed near the end of the graft on the stent side. You may do so.

According to the treatment device according to one embodiment of the present invention, the outer layer portion, the inner layer portion, and the folded portion are provided in the cover, respectively, and the stent graft in the first region of the stent graft is provided with the inner layer portion and the folded portion. However, since it is held between the outer layer portion and the shaft in a diameter-reduced state, the following is obtained. In other words, it is possible to avoid the possibility that the additional structural portion will interfere with the operation on the hand side when the stent in the reduced diameter state is deployed from the inside of the cover by the pulling operation. Therefore, by performing treatment using a treatment apparatus having such a cover, it is possible to improve convenience during treatment.

1 is a schematic diagram showing a schematic configuration example of a treatment apparatus according to an embodiment of the present invention; FIG. 2 is a schematic diagram showing an example of the detailed configuration inside the cover shown in FIG. 1, etc. FIG. FIG. 2 is a schematic diagram showing a detailed configuration example of the stent graft shown in FIG. 1; FIG. 2 is a schematic diagram showing an example of how to use the treatment apparatus shown in FIG. 1; FIG. 5 is a schematic diagram showing an example of a treatment method following FIG. 4 ; FIG. 6 is a schematic diagram showing an example of a treatment method following FIG. 5 ; FIG. 4 is a schematic diagram showing an example of a method of placing a stent graft using a therapeutic device according to a comparative example; FIG. 4 is a schematic diagram showing an example of a method of placing a stent graft using a therapeutic device according to an embodiment; FIG. 9 is a schematic diagram showing an example of a placement method following FIG. 8;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The description will be given in the following order.
1. Embodiment (example of therapeutic device provided with a pull tube having a pusher)
2. Modification

<1. Embodiment>
[Outline configuration]
FIG. 1 is a schematic side view showing an example of a schematic configuration of a therapeutic device (therapeutic device 5) according to an embodiment of the present invention. The therapeutic device 5 is a device used for treatment of arterial dissection or the like using the OSG method, for example. In this example, as shown in FIG. A tube 41 is provided. Although the details will be described later, the stent graft 2 is designed to be indwelled in a site to be treated (for example, in a blood vessel such as an artery) using the catheter 1 during the treatment described above.

(Catheter 1)
A catheter 1 is a medical device used when carrying a stent graft 2 to the site to be treated in a patient. This catheter 1, as shown in FIG. 1, has a delivery shaft 11 and a handle 12 (grasping portion, grip). The delivery shaft 11 corresponds to a specific example of "shaft" in the present invention.

The delivery shaft 11 is made of a flexible tubular structure (tubular member), and has a shape that extends (stretches) along the Z-axis direction, which is its own axial direction (longitudinal direction). In the distal end region along the axial direction of the delivery shaft 11, as shown in FIG. ) is held inside a cover 3 to be described later in a reduced diameter state. Also, the base end region of the delivery shaft 11 corresponds to the portion accommodated within the handle 12 . The intermediate area between the distal area and the proximal area is an area located between the cover 3 and the handle 12 as shown in FIG.

The length (total length) along the axial direction of the delivery shaft 11 is, for example, about 300 to 900 mm, preferably about 400 to 800 mm, more preferably about 450 to 600 mm. , 570 mm. In addition, the length of the tip region described above is appropriately set according to the length of the stent graft 2 to be mounted, and is, for example, about 30 to 350 mm, preferably about 50 to 300 mm, more preferably about 50 to 300 mm. It is about 100 to 280 mm. The length of the intermediate region is, for example, approximately 100 to 250 mm, preferably approximately 120 to 220 mm, more preferably approximately 130 to 200 mm, and a preferred example is 150 mm.

Further, the outer diameter of the tip region is, for example, about 5 to 20 mm, preferably about 8 to 15 mm, and a preferred example is 11 mm. The outer diameter of the intermediate region is, for example, approximately 5 to 20 mm, preferably approximately 8 to 15 mm, and a preferred example is 10 mm.

As shown in FIG. 1, the handle 12 is attached to the proximal end portion (base end region) of the delivery shaft 11, and is the portion that the operator (doctor) grasps (grips) when using the catheter 1. The handle 12 has a shape extending along its axial direction (Z-axis direction).

The length of the handle 12 along the axial direction is, for example, about 50 to 200 mm, preferably about 60 to 180 mm, more preferably about 80 to 170 mm, and a preferred example is 145 mm. The outer diameter of the handle 12 is, for example, approximately 3 to 50 mm, preferably approximately 5 to 25 mm, and a preferred example is 20 mm. The handle 12 is made of synthetic resin such as polycarbonate or acrylonitrile-butadiene-styrene copolymer (ABS).

Here, FIG. 2 (FIG. 2(A), FIG. 2(B)) is a side view schematically showing an example of the detailed configuration inside the cover 3 shown in FIG. In addition, in FIG. 2B, illustration of the stent 21 in the cover 3 is omitted for the sake of convenience. FIG. 3 schematically shows a detailed configuration example of the stent graft 2 shown in FIG. Specifically, FIG. 3A schematically shows an example of the external configuration of the stent graft 2, and FIG. there is

(Stent graft 2)
The stent graft 2, as shown in FIGS. 1 and 3, has a tubular (cylindrical) structure extending along its axial direction (Z-axis direction), and includes a stent 21, a graft 22 and a cuff portion. 23 (see FIG. 3). Also, this stent graft 2 (stent 21) has a self-expanding structure that can be held in a reduced diameter state. The length of the stent graft 2 when expanded along the axial direction is, for example, about 270 to 370 mm. The expanded outer diameter of the stent 21 is, for example, about 30 mm, and the expanded inner diameter of the stent 21 is, for example, about 28 mm.

As shown in FIGS. 1 and 3, the stent 21 is configured using one or a plurality of wire rods W (element wires), and in this example has a tubular (cylindrical) structure. Specifically, for example, this tubular structure is configured by a mesh structure, and such a tubular mesh structure is formed by braiding the wire W in a predetermined pattern. The knitting pattern includes, for example, plain weave, twill weave, and knitting. Alternatively, a cylindrical network structure may be formed by arranging one or more cylindrically processed wire rods W that are bent in a zigzag shape.

As the material of the wire rod W, a metal wire rod is preferable, and in particular, a shape memory alloy, which is imparted with a shape memory effect and superelasticity by heat treatment, is preferably adopted. However, depending on the application, stainless steel, tantalum (Ta), titanium (Ti), platinum (Pt), gold (Au), tungsten (W), or the like may be used as the material of the wire W. Examples of the above-mentioned shape memory alloy include nickel (Ni)-Ti alloy, copper (Cu)-zinc (Zn)-X (X = aluminum (Al), iron (Fe), etc.) alloy, Ni-Ti-X (X=Fe, Cu, vanadium (V), cobalt (Co), etc.) alloys and the like are preferably used. As such a wire W, for example, a synthetic resin may be used. Also, a metal wire whose surface is coated with Au, Pt, etc. by means of plating, etc., or a composite wire, in which a core made of a radiopaque material such as Au, Pt, etc. is covered with an alloy, is used as a wire. W may be used.

The graft 22 has a tubular (cylindrical) shape as shown in FIGS. 1 and 3, and is arranged on the proximal end side of the stent 21 and the cuff portion 23 (see FIG. 3). In addition, as shown in FIG. 3, the cuff 23 is arranged near the end of the graft 22 on the side of the stent 21 . Specifically, for example, as shown in FIG. 3B, the cuff 23 is arranged so as to cover the outer peripheral side of the graft 22 in the vicinity of such an end. Also, in the region within the cuff portion 23, the portions near the ends of the graft 22 and the stent 21 are sutured together (see FIG. 3(B)).

Here, the graft 22 and the cuff portion 23 each correspond to a specific example of the "additional structural portion" in the present invention. Alternatively, the graft 22 and the cuff portion 23 may be fixed to the delivery shaft 11 and the handle 12, respectively. This is because such a configuration prevents the graft 12 and the cuff portion 23 from being dislocated due to the retraction of the cover 3 .

Here, in the examples shown in FIGS. 1 and 3, the first region A1 and the second region A2 are provided along the axial direction (Z-axis direction) of the stent graft 2. The first area A1 is located on the distal end side of the stent graft 2 and is an area where only the stent 21 is arranged. On the other hand, the second region A2 is located on the proximal side of the stent graft 2 (the proximal side of the first region A1) and is a region where at least the graft 22 and the cuff portion 23 are arranged. In addition, in the example of the present embodiment, the graft 22 and the cuff portion 23 are arranged in the second region A2, and the stent 21 is not arranged, but the present invention is not limited to this example. That is, in the second region A2, in addition to the graft 22 and the cuff portion 23, the stent 21 may also be arranged (on the inner peripheral side of the graft 22).

The length of the first region A1 when expanded along the axial direction is, for example, about 200 mm, and the length of the second region A2 along the axial direction is, for example, about 70 to 170 mm. The axial length of the graft 22 is, for example, about 50 to 150 mm, and the axial length of the cuff portion 23 is, for example, about 20 mm.

As such a graft 22, for example, a thermoplastic resin is formed into a tubular shape by a molding method such as extrusion molding or blow molding, or a knitted or woven fabric made of thermoplastic resin fibers or ultrafine metal wires formed into a tubular shape. , Cylindrical nonwoven fabrics made of thermoplastic resin or ultra-fine metal, Cylindrical flexible resin sheets or porous sheets, Solvent-dissolved resin formed into thin cylinders by electrospinning structure, etc. can be used.

Here, as the knitted fabric described above, known knitted fabrics and woven fabrics such as plain weave and twill weave can be used. In addition, it is also possible to use a material with pleats such as crimping. Among these, woven and woven fabrics of thermoplastic resin fibers formed in a cylindrical shape, and furthermore, plain weave fabrics of thermoplastic resin fibers formed in a cylindrical shape are excellent in strength, porosity, and productivity. can be said to be preferable.

Examples of the above thermoplastic resins include polyolefins such as polyethylene, polypropylene, and ethylene-α-olefin copolymers, polyamides, polyurethanes, polyethylene terephthalate, polybutylene terephthalate, polycyclohexane terephthalate, polyethylene-2,6-naphthalate, and the like. polyester, fluororesin such as polyethylene fluoride and polypropylene fluoride, and other resins with less durability and tissue reaction can be used. Of these, polyesters such as polyethylene terephthalate, and fluororesins such as polyethylene fluoride and polypropylene fluoride, which are chemically stable, highly durable, and less prone to tissue reaction, can be preferably used.

(Cover 3)
As described above, the cover 3 is a member for holding the stent 21 of the stent graft 2 in a diameter-reduced state in the distal region of the delivery shaft 11 . Specifically, in this example, as shown in FIGS. 1 to 3, the first area A1 is located on the distal side of the delivery shaft 11, and the second area A2 is located on the proximal side of the delivery shaft 11. , the stent 21 in the first region A1 is held within the cover 3 . The outer diameter of the cover 3 is, for example, approximately 5.0 to 20.0 mm, preferably approximately 10 to 15 mm.

Such a cover 3 is composed of a soft cover in this example. By covering the diameter-reduced stent 21 with a soft cover, the stent 21 can be reliably held. Further, since the cover 3 is soft, it is possible for the cover 3 to easily follow changes in the shape of the distal end region of the delivery shaft 11 compared to a hard tubular body (sheath) or the like. .

Here, as shown in FIGS. 1, 2(A), and 2(B), the cover 3 of this embodiment has a cylindrical structure extending along the axial direction. The axial length of the cover 3 (the total length of the outer layer portion 32, the inner layer portion 31 and the folded portion 33: the total length of the cover 3) is, for example, about 300 to 1300 mm.

Such a cover 3 has a two-layer structure (double structure) having an inner layer portion 31 and an outer layer portion 32 as shown in FIGS. 1, 2(A) and 2(B). In other words, the cover 3 has a cylindrical outer layer portion 32 and an inner layer portion 31 positioned on the inner peripheral side of the outer layer portion 32 . In the example shown in FIG. 2A , the outer layer portion 32 is positioned on the outer peripheral side of the delivery shaft 11 and the inner layer portion 31 is positioned on the inner peripheral side of the delivery shaft 11 . Further, the cover 3 is provided with a folded portion 33 which is a portion that connects (connects) the outer layer portion 32 and the inner layer portion 31 at the distal end side of the delivery shaft 11 (see FIGS. 1 and 2). (A)). Specifically, the cover 3 is formed by folding a cylindrical tube member inward, and the folded portion corresponds to the inner layer portion 31 . 1, 2(A), and 2(B), the proximal side of the inner layer portion 31 extends to the proximal side of the catheter 1 through the delivery shaft 11. exist. Specifically, as shown in FIG. 1 , the proximal end side of the inner layer portion 31 is inserted through the insides of the delivery shaft 11 and the handle 12 , respectively, and protrudes from the proximal end side of the handle 12 .

Here, as shown in FIG. 2(A), the stent 21 of the stent graft 2 is held between the outer layer portion 32 of the cover 3 and the delivery shaft 11 in the diameter-reduced state described above. (see arrow P0). In addition, in the present embodiment, as shown in FIGS. 1 and 2A, for example, a marker 310 is provided in the base end region of the inner layer portion 31 of the cover 3 (the inner region of the handle 12). The marker 310 indicates the start timing of the pull tube 41, which will be described later, after the operation of pulling the cover 3 (inner layer portion 31), which will be described later, is started. It is

The cover 3 (the outer layer portion 32, the inner layer portion 31, the folded portion 33, etc.) is made of, for example, a material exhibiting translucency or transparency (optical transparency). Examples of such translucent or transparent materials include polyolefins such as polyethylene, polypropylene, and ethylene-α-olefin copolymers, polyamides, polyimides, polyurethanes, polyethylene terephthalate, polybutylene terephthalate, polycyclohexane terephthalate, Polyester such as polyethylene-2,6-naphthalate, fluororesin such as polyethylene fluoride and polypropylene fluoride, woven fabric or knitted fabric made of fibers of resin such as silicone, or structure such as film or sheet, or a combination thereof things, etc. For the purpose of reinforcement or the like in these, thin wires or short fibers such as metal may be included. By the way, as the member constituting the cover 3, there are those which are manufactured in advance into a cylindrical shape using the above-mentioned materials, those which are flat and processed into a cylindrical shape, and those which are a combination thereof. mentioned.

Due to such a configuration of the cover 3, an operation for expanding the stent graft 2 is performed by pulling the cover 3, which will be described later. The details of the operation of expanding the stent graft 2 (the method of placing the stent graft 2 during treatment) will be described later (FIGS. 8 and 9).

(Pull tube 41)
As shown in FIGS. 1, 2A, and 2B, the pull tube 41 described above extends along the axial direction (Z-axis direction) from the vicinity of the distal end of the catheter 1 to the proximal end side. It is a tubular member. Specifically, the pull tube 41 is located near the tip of the delivery shaft 11 (as shown in FIG. 2A, between the outer layer portion 32 and the inner layer portion 31 of the cover 3). (arranged between the layers of the stent 21), and protrudes from the proximal side of the handle 12 through the inside of the handle 12 or the like. In addition, as shown in FIG. 2B, the pull tube 41 has a half-split shape in which the base end portion is split in half along the radial direction (the lower half is a notch). It has become. This is to prevent the base end portion of the pull tube 41 from coming into contact with the handle 12 . The axial length of the pull tube 41 (axial length L41 shown in FIG. 2B) is, for example, about 300 to 700 mm. Further, the axial length L40 (see FIG. 2(B)) of the half portion of the pull tube 41 is, for example, about 370 mm.

As shown in FIGS. 1, 2A, and 2B, at the distal end of the pull tube 41 is a pusher 42 which abuts the stent 21 on the distal end side of the stent 21 in a diameter-reduced state. is provided. Specifically, as shown in FIG. 2(A), the pusher 42 is disposed between the stent 21 in a diameter-reduced state and the folded portion 33 on the outer peripheral side of the delivery shaft 11 . An axial length L42 (see FIG. 2B) of such a pusher 42 is, for example, about 10 mm.

[Operation and action/effect]
(A. Basic operation)
The therapeutic device 5 of this embodiment is used, for example, in the treatment of arterial dissection or the like. Specifically, the operator manipulates the catheter 1 to carry the stent graft 2 in a reduced diameter state to a site to be treated (for example, inside a blood vessel such as an artery) in a patient, and then indwell it after being expanded. . By indwelling the stent graft 2 at the site to be treated in this manner, it is possible to expand and maintain the vascular lumen while suppressing blood flow to the cleft of the inner wall of the blood vessel. In particular, the stent graft 2 is used, for example, in treatment using the OSG method, which is one of treatment methods such as arterial dissection in the thoracic aorta.

Here, with reference to FIGS. 4 to 6, an outline of a treatment method for arterial dissection or the like using this OSG method (a method of using the treatment device 5) will be described.

4 to 6 are schematic diagrams of an example of how to use the treatment device 5 during such treatment. Here, the artery 9 (thoracic aorta), which is the blood vessel to be treated, is a portion including the distal arch aorta (the portion of the arch bifurcation 9B shown in FIGS. 4 to 6) and the proximal descending aorta. A certain case will be described as an example. In addition, FIG. 6 also shows an enlarged view of the portion indicated by reference numeral P7.

First, as shown in FIG. 4, for example, in this OSG method, after the patient's chest is opened, a portion of the artery 9 is incised using the therapeutic device 5 configured as shown in FIGS. The stent graft 2 in a reduced diameter state is inserted through the opening (see arrow P8). Specifically, the stent graft 2 is inserted from the distal end side (cover 3 side) of the delivery shaft 11 in the catheter 1 . At this time, as shown in FIGS. 1 and 2A, for example, the stent graft 2 is held inside the cover 3 at the distal end region of the delivery shaft 11 of the catheter 1 in a reduced diameter state.

Here, when the artery 9 to be treated is, for example, in an arterial dissection state, the artery 9 contains an arterial lumen (true lumen), which is the original blood flow path, and a new artery caused by tearing the inner wall of the blood vessel. There will be a lumen (false lumen). In such a case, the catheter 1 is inserted along a predetermined guide wire in order to avoid the risk of the catheter 1 being erroneously inserted into the false lumen. That is, the catheter 1 is inserted while inserting such a guide wire into the lumen of the catheter 1 .

Specifically, first, a guide wire is inserted into the artery 9 from the patient's groin (groin), passed through the artery 9, and pulled out from the opening described above. Since the guidewire is inserted into the artery 9 from the peripheral side, the guidewire is reliably inserted into the true lumen without being accidentally inserted into the false lumen. The length of such a guide wire is, for example, approximately 50 to 450 cm, and its outer diameter is, for example, approximately 0.2 to 1.0 mm.

Subsequently, the catheter 1 is inserted into the artery 9 along the guide wire using the opening as an entrance (see arrow P8 in FIG. 4). As described above, since the guide wire is surely inserted into the true lumen, by inserting the catheter 1 into the artery 9 along the guide wire, the catheter 1 can also be reliably inserted. It will be inserted into the true lumen. That is, even in the case of arterial dissection, the risk of the catheter 1 being inserted into the false lumen is avoided.

Next, as shown in FIG. 4, for example, the treatment device 5 is used to allow the stent graft 2 to reach a site in the artery 9 beyond the site to be treated (near the arterial dissection site) (see arrow P8). ).

Subsequently, by using the self-expanding force of the stent 21, the diameter of the stent graft 2 is expanded (deployed). Specifically, first, the operator of the catheter 1 performs a pulling operation (pulling operation to the proximal end side) on the cover 3 and the like, which will be described later. Then, the cover 3 is removed from the stent graft 2, details of which will be described later. As a result, this stent graft 2 gradually expands due to the self-expanding force of the stent 21 . After that, the catheter 1, the cover 3 and the pull tube 41 are each removed from the patient's body.

In this way, the stent graft 2 is fixed to the inner wall of the artery 9, for example as shown in FIG. As a result, the lumen of artery 9 near the site of arterial dissection formation is dilated and retained. After that, the graft 22 is cut to a required length, and the cuff portion 23 is also cut to a required length.

Then, for example, as shown in FIG. 6, felt 80 is wrapped around the outer peripheral side of the cuff portion 23 and anastomosed, and the proximal end side of the cuff portion 23 is anastomosed with the artery 9 (arch aorta) (reference P80). reference). Further, the felt 80 is wrapped around the outer peripheral side of the proximal end of the graft 22 and anastomosed, and this anastomosed portion and the aorta arch are anastomosed (see symbol P80).

In this way, the stent graft 2 covers the inner periphery near the artery dissection formation site, allowing blood flow to pass through the stent graft 2, blocking the inflow of blood into the cleft (false lumen) in the inner wall of the blood vessel. will be

In particular, in the treatment method using this OSG method, compared with the treatment method (conventional treatment method) in which a catheter is inserted from the patient's groin (groin) to carry the stent graft to the treatment target site, the following points are observed. You get the advantage. That is, there is the advantage of being able to treat sites with important branches (eg, the aortic arch) that are extremely difficult to treat with this conventional treatment method. In addition, compared with the method of resecting the lesion site, replacing it with an artificial blood vessel, and anastomosing both ends of the anastomosis, the descending aorta suture (peripheral anastomosis) is replaced by fixation with the stent graft 2 . In other words, the OSG method omits the anastomosis between the distal end of the stent graft 2 and the descending aorta, thereby simplifying the anastomosis. Therefore, the operation time (extracorporeal circulation time) can be shortened, and the left thoracotomy or large chest incision required for suturing the descending aorta can be avoided, thereby reducing the surgical invasiveness to the patient (treatment reduce the burden on the patient when Furthermore, this OSG method has the advantage that the grafting range of the artificial blood vessel can be set in a wide range, and surgical treatment of nearby complications is also possible. In addition, since the stent graft applied to the OSG method is not introduced from the groin as in the above-described conventional treatment method, there is no need to pass through a thin blood vessel, and the outer diameter can be reduced to some extent even when the diameter is reduced. Even if it is big (thick), it is good.

Furthermore, in the present embodiment, as shown in FIGS. 5 and 6, for example, the gap between the stent 21 and the branching portion (arch bifurcation 9B) from the blood vessel (artery 9, etc.) in which the stent graft 2 is placed is reduced. From there, blood begins to flow. Therefore, reconstruction treatment (anastomosis with an artificial blood vessel, etc.) for this bifurcated portion becomes unnecessary, so that it is possible to shorten the operation time and reduce invasiveness during treatment.

(B. Functions and effects of cover 3, etc.)
Next, with reference to FIGS. 7 to 9 in addition to FIGS. 1 to 6, the action and effect of the cover 3 and the like of the present embodiment will be described in detail while comparing with a comparative example.

FIG. 7 schematically shows an example of a placement method of the stent graft 2 when using a therapeutic device (therapeutic device 105) according to a comparative example. 8 and 9 schematically show an example of a placement method of the stent graft 2 when using the therapeutic device 5 of this embodiment. 7 and 8 also show the insertion direction (arrow P8) of the catheter into the artery 9 described above with reference to FIG. In addition, in the comparative example shown in FIG. 7, only the stent 21 of the stent graft 2 is illustrated for convenience, and the illustration of the graft 22 and the cuff portion 23 is omitted.

(B-1. Placement method of comparative example)
First, in the therapeutic device 105 of the comparative example shown in FIG. 7, the stent graft 2 is placed in the blood vessel (artery 9) to be treated as follows. In the treatment apparatus 105 of this comparative example, instead of the cover 3 and the delivery shaft 11 described above in the treatment apparatus 5 of the embodiment, a cover 103 and a delivery shaft 101 are provided, and the pull tube 41 described above is provided. It's something you don't want to do. Further, in the treatment apparatus 105 of this comparative example, unlike the treatment apparatus 5 of the present embodiment described above (see FIG. 2A), as shown in FIG. and the delivery shaft 11 (between layers), the stent graft 2 (stent 21, etc.) in a reduced diameter state is arranged (see arrow P0).

In this comparative example, first, a catheter is inserted into the artery 9 (see arrow P8), as shown in FIG. 7(A), for example. Then, for example, as shown in FIG. 7B, the operator of this catheter pulls the proximal end of the outer layer 32 of the cover 103 toward the proximal end of the delivery shaft 101 (see arrow P101). By performing such a pulling operation on the outer layer portion 32 of the cover 103, the inner layer portion 31 of the cover 103 is gradually pulled out toward the proximal end side of the delivery shaft 11 via the folded portion 33 (see arrow P102). ). Then, as shown in FIG. 7B, for example, the diameter-reduced stent graft 2 is sequentially expanded from within the cover 103 by the self-expanding force of the stent 21, and expands in diameter (see arrow P103). Specifically, the stent graft 2 is gradually deployed from the distal end side to the proximal end side to expand its diameter. As a result, the entire stent graft 2 is finally deployed and expanded in diameter.

However, in the comparative example using the therapeutic device 105 having such a cover 103 and the like, when the diameter-reduced stent graft 2 is deployed from within the cover 103 and expanded in diameter by the pulling operation described above, for example, the following Problems such as

That is, first, in this comparative example, as described above, the stent graft 2 (stent 21 or the like) having a reduced diameter is arranged between the inner layer portion 31 of the cover 103 and the delivery shaft 101, and the outer layer portion 32 of the cover 103 is arranged. A pulling operation is performed on the proximal side of the . Therefore, when the outer layer portion 32 of the cover 103 is pulled, the graft 22 and the cuff portion 23 (additional structure portion) located on the proximal side (second region A2) of the stent 21 are pulled from the proximal side (base portion). (end side) may interfere with the operation.

In addition, when the stent 21 is deployed, it also extends along its axial direction (Z-axis direction). There is a risk that an abrupt shortening action toward the proximal end may occur when doing so. If such a jumping phenomenon of the stent 21 increases, the placement position of the stent graft 2 may be displaced, or the patient's blood vessel (artery 9 or the like) may be damaged.

For these reasons, in this comparative example, convenience may be impaired when treating arterial dissection using the OSG method.

(B-2. Placement method according to the present embodiment)
On the other hand, in the treatment apparatus 5 of the present embodiment shown in FIGS. 8 and 9, the cover 3 described above is used to attach the stent graft 2 to the blood vessel (artery 9) to be treated as follows. placement is performed.

That is, first, as shown in FIG. 8(A), for example, the catheter 1 is inserted into the artery 9 (see arrow P8). Then, the operator of the catheter 1 performs an operation (first pulling operation) of pulling the proximal end side of the inner layer portion 31 of the cover 3 in the proximal direction of the catheter 1 (see arrow P11). By performing such a pulling operation on the inner layer portion 31 of the cover 3, the outer layer portion 32 of the cover 3 is pulled into the delivery shaft 11 via the folded portion 33 (see arrow P2), and the catheter 1 is pulled. It will be gradually pulled proximally.

Therefore, for example, as shown in FIG. 8B, the stent 21 in a diameter-reduced state is sequentially deployed from within the cover 3 by the self-expanding force of the stent 21, and expands in diameter (see arrow P3). . Specifically, the stent 21 is gradually deployed from its proximal end toward its distal end to expand its diameter.

Subsequently, as shown in FIGS. 9A and 9B, for example, the operator of the catheter 1 pulls the pull tube 41 toward the proximal end of the delivery shaft 11 (second pulling operation). is performed (see arrow P12). That is, in the example shown in FIGS. 8 and 9, after the pulling operation (first pulling operation) on the inner layer portion 31 of the cover 3 is started, the pull tube 41 is pulled (second pulling operation). is started. After the start of the first pulling operation, the start timing of the second pulling operation can be determined by the operator using a marker 310 provided in the base end region of the inner layer portion 31 of the cover 3. will be grasped by In other words, the timing at which such a marker 310 is displaced from the inside of the handle 12 to the outside as shown in FIGS. As a result, the above-described second pulling operation is started.

In this manner, in addition to the pulling operation on the inner layer portion 31 of the cover 3, the pulling operation on the pull tube 41 is also performed, resulting in the following. That is, as shown in FIGS. 9A to 9C, for example, the diameter-reduced stent 21 is pushed toward the proximal end of the delivery shaft 11 by the pusher 42 (see arrow P4). , it is deployed from inside the cover 3 and expanded in diameter (see arrow P3). As a result, the stent 21 gradually moves toward the proximal side and is gradually deployed from the distal side toward the proximal side to expand its diameter.

As a result, as shown in FIG. 9C, the stent 21 as a whole is finally deployed and expanded in diameter. The start timing of the second pulling operation (pulling operation on the pull tube 41) after the start of the first pulling operation is preferably set within the following range, for example. That is, when LA1 is the length of the first region A1 and LB1 is the axial length of the portion of the stent 21 exposed to the outside by the first pulling operation (the length of the exposed portion of the stent 21), for example, the following (1) It is desirable to start the second pulling operation within the range that satisfies the formula.
0.3≦(LB1/LA1)≦0.7 (1)

(B-3. Action and effect)
Thus, in the therapeutic device 5 of the present embodiment, the outer layer portion 32, the inner layer portion 31, and the folded portion 33 are provided on the cover 3, respectively, and the stent 21 in the first region A1 of the stent graft 2 is provided. is held between the outer layer portion 32 and the delivery shaft 11 in a reduced diameter state. Thus, in the present embodiment, when the diameter-reduced stent 21 is expanded from the cover 3 by pulling the proximal end side of the inner layer portion 31 of the cover 3 toward the proximal direction of the catheter 1, the diameter of the stent 21 is expanded. , becomes:

That is, the outer layer portion 32 of the cover 3 is pulled into the delivery shaft 11 through the folded portion 33 and gradually pulled toward the proximal end of the catheter 1, so that the diameter-reduced stent 21 self-expands. Due to the force, they are sequentially deployed from the inside of the cover 3 and expanded in diameter. Therefore, for example, as in the comparative example, the stent graft 2 (stent 21 or the like) having a reduced diameter is arranged between the inner layer portion 31 of the cover 103 and the delivery shaft 101, and the proximal end of the outer layer portion 32 of the cover 103 is placed. Unlike the case where the pulling operation is performed to the side, it is as follows. That is, when the stent 21 in a diameter-reduced state is pulled out from within the cover 3, the graft 22 and the cuff portion 23 (additional structural portion) positioned on the proximal end side (second region A2) of the stent 21 are This avoids the possibility of obstructing the operation on the proximal side (proximal side). Therefore, in the present embodiment, by performing treatment using the treatment device 5 having such a cover 3, it is possible to improve the convenience of the above-described treatment.

In addition, in the present embodiment, a pull tube 41 is provided that extends from the vicinity of the distal end of the catheter 1 to the proximal end along the axial direction (Z-axis direction), and at the distal end of the pull tube 41, A pusher 42 is provided on the distal end side of the stent 21 in a diameter-reduced state to abut against the stent 21 . Therefore, when deploying the stent 21 in a diameter-reduced state from the inside of the cover 3, it is necessary to pull the catheter 1 toward the proximal end of the pull tube 41 in addition to pulling the inner layer portion 31 of the cover 3 toward the proximal end. What is done is as follows. That is, the diameter-reduced stent 21 is pushed toward the proximal end of the delivery shaft 11 by the pusher 42, and is deployed from the cover 3 and expanded in diameter. ) gradually moves to the proximal side, the stent 21 is deployed from the proximal side. Therefore, when the stent graft 2 is left in the patient's body, the above-described jumping phenomenon of the stent 21 can be suppressed (for example, the "x" mark indicated by the dashed arrow m in FIG. 9C). See) As a result, it is possible to further improve the convenience of treatment.

Furthermore, in the present embodiment, after the operation of pulling the proximal end of the inner layer portion 31 of the cover 3 toward the proximal direction of the catheter 1 (first pulling operation) is started, the pull tube 41 is pulled from the proximal end of the catheter 1 . By performing the operation of pulling in the end direction (second pulling operation), the stent 21 in a diameter-reduced state is pushed toward the proximal end side of the delivery shaft 11 by the pusher 42, and is pulled into the cover 3. It is designed to be deployed from and expanded in diameter. In this manner, the second pulling operation is started after the first pulling operation is started, so that when the stent graft 2 is indwelled in the patient's body, the stent is pulled as described above. 21 jumping phenomenon can be suppressed.

In addition, in the present embodiment, the above-described marker 310 is provided in the base end region of the inner layer portion 31 of the cover 3, so the following is achieved. That is, by using such a marker 310, the operator can easily grasp the guideline of the start timing of the above-described second pulling operation after the start of the above-described first pulling operation. As a result, it is possible to further improve the convenience of treatment.

<2. Variation>
Although the present invention has been described above with reference to the embodiments, the present invention is not limited to these embodiments, and various modifications are possible.

For example, the configuration (shape, arrangement position, size, number, material, etc.) of each member described in the above embodiment is not limited, and other shapes, arrangement positions, sizes, numbers, materials, etc. may be used. . Specifically, in the above-described embodiment, an example of the configuration of the cover 3 has been specifically described. The shape, arrangement position, size, number, material, and the like may be used. Specifically, for example, the inner layer portion 31 of the cover 3 may not be provided with the markers 310 described above.

In addition, in the above-described embodiment, as an example of the "additional structural section" in the stent graft of the present invention, a case in which the graft 22 and the cuff section 23 are included has been described as an example, but the present invention is not limited to this example. . That is, for example, at least one of the graft 22 and the cuff portion 23 may be omitted from the stent graft 2, or another member may be included as the "additional structural portion" described above. Also, for example, the graft 22 may be further provided with a branched feeding tube.

Furthermore, in the above embodiment, the case where the inner layer portion 31 and the outer layer portion 32 of the cover 3 are integrated with each other via the folded portion 33 has been described, but the present invention is not limited to this case. That is, for example, the inner layer portion and the outer layer portion of the cover are separated from each other, and the inner layer portion and the outer layer portion are connected (connected) by the separate folding portion (connecting portion). You may do so.

Further, in the above-described embodiment, a specific configuration example of the pull tube 41 has been described, but it is not limited to this configuration example. Specifically, for example, the pusher 42 described above may not be provided at the tip of the pull tube 41 . In some cases, for example, the pull tube 41 itself may not be provided inside the therapeutic device 5 .

In addition, in the above embodiment, the stent graft is provided with one each of the first region arranged on the distal side within the cover and the second region arranged on the proximal side within the cover. Although the example of the case has been described, it is not limited to this example. That is, for example, another second region may be further provided on the distal end side of the first region in the stent graft. In other words, in the stent graft, the first region may be sandwiched between two second regions.

Further, in the above embodiment, the method of placing a stent graft using a treatment device has been described with specific examples, but the method of placing a stent graft is limited to the example described in the above embodiment. Absent. Specifically, for example, in the above-described embodiment, after the pulling operation (first pulling operation) on the base end side of the inner layer portion 31 of the cover 3 is started, the pulling operation (second pulling operation) on the pull tube 41 is performed. ) is started, but it is not limited to this example. That is, for example, the first and second pulling operations are performed in parallel, respectively, or conversely, depending on the case, the first pulling operation is performed after the second pulling operation is initiated. An operation may be initiated.

Furthermore, in the above embodiment, the case where the therapeutic device is configured by the catheter, the stent graft, and the cover has been described as an example, but the present invention is not limited to this. That is, for example, the therapeutic device may be configured with only the catheter, the therapeutic device with the catheter and the stent graft, or the therapeutic device with the catheter and the cover.

In addition, in the above-described embodiments, treatment devices (catheters, stent grafts, covers, etc.) that are mainly applied to treatment of the thoracic aorta, including the distal arch aorta and the proximal descending aorta, will be described as examples. However, it is not limited to this example. That is, the treatment apparatus of the present invention can also be applied to treatment of blood vessels such as other arteries (for example, ascending aorta, thoracoabdominal aorta, abdominal aorta, iliac artery, femoral artery, etc.). is.

Claims

a catheter having an axially extending shaft;
a first region including a stent and an additional structural portion, wherein only the stent is arranged along the axial direction; and a second region in which at least the additional structural portion is arranged; a stent graft having
In the distal region of the shaft, the stent in the first region is reduced in diameter such that the first region is located on the distal side of the shaft and the second region is located on the proximal side of the shaft. and a cover for holding the
The cover is
a cylindrical outer layer portion positioned on the outer peripheral side of the shaft;
an inner layer portion located on the inner peripheral side of the shaft and extending through the shaft to the proximal end side of the catheter;
a folded portion that connects the outer layer portion and the inner layer portion on the distal end side of the shaft;
The therapeutic device, wherein the stent is held in the reduced diameter state between the outer layer and the shaft.
further comprising a pull tube extending from near the distal end of the catheter to the proximal end along the axial direction;
2. The treatment apparatus according to claim 1, wherein the distal end of the pull tube is provided with a pusher that contacts the stent on the distal end side of the stent in the reduced diameter state.
After starting a first pulling operation, which is an operation for pulling the proximal side of the inner layer portion of the cover in the proximal direction of the catheter,
By performing a second pulling operation, which is an operation of pulling the pull tube in the proximal direction of the catheter,
The treatment according to claim 2, wherein the diameter-reduced stent is expanded from within the cover while being pushed toward the proximal end of the shaft by the pusher. Device.
In the base end region of the inner layer portion of the cover,
4. The treatment apparatus according to claim 3, wherein a marker is provided to indicate an approximate start timing of the second pulling operation after the start of the first pulling operation.
The additional structural part is
a tubular graft;
a cuff disposed near an end of the graft on the stent side;
5. The therapeutic device of any one of claims 1-4, comprising: