WO2023281598A1

WO2023281598A1 - Therapeutic device

Info

Publication number: WO2023281598A1
Application number: PCT/JP2021/025347
Authority: WO
Inventors: 邦生桑原; 英一中野; 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: JPWO2023281598A1

Abstract

A therapeutic device according to one embodiment of the present invention comprises: a catheter having a shaft that extends in the axial direction; a stent graft that is configured by including a cylindrical graft and a stent; and first and second covers that are for holding the stent graft in a reduced-diameter state in a leading-end region of the shaft and that are disposed so as to be separated from each other along the axial direction. The first cover is disposed on a base-end side of the second cover along the axial direction. The second cover has: a cylindrical outer layer portion situated on the outer circumferential side of the shaft; an inner layer portion that is disposed on the inner circumferential side of the shaft and the outer layer portion and that extends up to the base-end side of the catheter through the interior of the shaft; and a fold-back portion that connects the outer layer portion and the inner layer portion on the leading-end side of the shaft. The stent graft is so configured as to be held in a reduced-diameter state between the first cover and the shaft and between the shaft and the outer layer portion of the second cover.

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. 4494144

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 treatment device according to one embodiment of the present invention includes a catheter having a shaft extending along the axial direction, a stent graft including a tubular graft and a stent, and a stent graft at the distal end region of the shaft. first and second covers axially spaced apart from each other for retaining the reduced diameter condition. The first cover is arranged axially proximal to the second cover. The second cover has a cylindrical outer layer located on the outer peripheral side of the shaft, and the outer layer and the inner peripheral side of the shaft, and extends through the shaft to the proximal end side of the catheter. It has an inner layer portion and a folded portion connecting the outer layer portion and the inner layer portion on the distal end side of the shaft. A stent graft is held in a reduced diameter state between the first cover and the shaft and between the outer layer of the second cover and the shaft, respectively.

In the treatment apparatus according to one embodiment of the present invention, the cover for holding the stent graft in a diameter-reduced state in the distal end region of the shaft is the first cover on the proximal end side along the axial direction. , and the second cover on the distal end side along the axial direction. The stent graft is held in the reduced diameter state between the first cover and the shaft and between the outer layer portion of the second cover and the shaft. As a result, the proximal side of the first cover is pulled in the proximal direction of the shaft, and the proximal side of the inner layer of the second cover is pulled in the proximal direction of the catheter (pulling operation). As the radial stent-graft is deployed from within the first and second covers and expanded, the following occurs. That is, the stent graft is pulled along the axial direction toward the vicinity of the boundary between the first and second covers (near the intermediate position of the stent graft). As a result, when the expanded stent graft is left in the patient's body, displacement of the indwelling position (positional displacement in the axial direction) of the stent graft is suppressed.

In the treatment apparatus according to one embodiment of the present invention, the first pulling operation, which is an operation of pulling the proximal side of the first cover toward the proximal direction of the shaft, and the inner layer portion of the second cover and a second pulling operation, which is an operation of pulling the proximal side of the catheter in the proximal direction of the catheter, so that the stent-grafts in a reduced diameter state are deployed from inside the first and second covers, respectively. It may be arranged such that it expands in diameter. In this case, when the diameter-reduced stent graft is deployed from inside the first and second covers and expanded by performing the first and second pulling operations as the pulling operations, respectively. , the displacement of the indwelling position of the stent graft is suppressed as described above.

In this case, by starting the first pulling operation after starting the second pulling operation, the stent-grafts in the reduced diameter state are pulled from within the second and first covers, respectively, in this order. It may be adapted to be deployed and expanded in diameter. In this case, the deviation of the indwelling position of the stent graft described above can be more easily suppressed, and as a result, the convenience of the treatment can be further improved.

In addition, in the therapeutic device according to one embodiment of the present invention, the stent graft may be partially provided with a window portion in which at least the graft of the graft and the stent is not arranged. In this case, for example, blood flows from the window to a bifurcation (for example, arch bifurcation) from a blood vessel (artery or the like) in which the stent graft is placed. Therefore, reconstruction treatment (anastomosis with an artificial blood vessel, etc.) for this bifurcated portion is not necessary, so that the operation time can be shortened and the invasiveness can be reduced during the treatment.

In this case, in the diameter-reduced stent graft, the tip of the window may be located near the boundary between the first and second covers. In this case, when the diameter-reduced stent graft is expanded from within the first and second covers by the above-described pulling operation, the first and second covers are separated from each other as described above. As the stent-graft is pulled toward the boundary, the following is true. That is, since the tip of the window portion is positioned near such a boundary, when the expanded stent graft is placed in the patient's body, the window portion may be misaligned (displaced in the axial direction). ) is suppressed. As a result, convenience during treatment is further improved.

According to the therapeutic device according to one embodiment of the present invention, the cover for holding the stent graft in a diameter-reduced state at the distal end region of the shaft is arranged separately from the first and second covers. As a result, displacement of the placement position of the stent graft within the patient's body can be suppressed. Therefore, by performing treatment using a treatment apparatus having such first and second covers, it is possible to improve the convenience of 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. 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. 10 is a schematic diagram showing a configuration example of a stent graft applied to a treatment device according to a modification;

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 having two types of covers arranged separately from each other)
2. Modification (another configuration example of a stent graft applied to a therapeutic device)
3. Other variations

<1. Embodiment>
[Outline configuration]
FIG. 1 is a schematic side view showing an example of a schematic configuration of a therapeutic device (therapeutic device 4) according to an embodiment of the present invention. The therapeutic device 4 is a device used for treatment of arterial dissection or the like using the OSG method, for example, and in this example, as shown in FIG. ing. 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). At the distal end region of the delivery shaft 11 along the axial direction, as shown in FIG. 1, the stent graft 2, which will be described later, is held inside the cover 3, which will be described later, with its diameter reduced, as shown in FIG. It has become so. Also, the base end region of the delivery shaft 11 corresponds to the portion accommodated within the handle 12 . The intermediate region between the distal end region and the proximal end region is a region located between the cover 3 and the handle 12 as shown in FIG. there is

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 750 mm. , 670 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 300 mm, preferably about 50 to 270 mm, more preferably about 50 to 270 mm. It is about 80 to 250 mm. The length of the intermediate region is, for example, approximately 100 to 600 mm, preferably approximately 150 to 550 mm, more preferably approximately 200 to 500 mm, and a preferred example is 260 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 150 mm, and a preferred example is 130 mm. The outer diameter of the handle 12 is, for example, approximately 3 to 30 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 is a side view schematically showing an example of the detailed configuration inside the cover 3 shown in FIG. FIG. 3 schematically shows a detailed configuration example of the stent graft 2 shown in FIG.

(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 and a graft 22. It is configured. Also, the stent graft 2 has a self-expanding structure that can be held in a reduced diameter state. The axial length of the stent graft 2 is, for example, about 150 to 270 mm. Further, the outer diameter of the stent graft 2 when expanded is, for example, about 17 to 39 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 to cover (cover) at least a portion of the stent 21 . Specifically, for example, the graft 22 is arranged so as to cover the inner peripheral side or the outer peripheral side of the stent 21 (wire W), or the graft 22 is arranged on the outer peripheral side and the inner peripheral side of the stent 21 (wire W). are arranged to cover both sides of the

In the example shown in FIG. 3, along the axial direction (Z-axis direction) of the stent graft 2, a stent-arranged area A1 and a stent-unarranged area A2 are provided. The stent arrangement area A1 is located on the distal end side of the stent graft 2 and is an area where the stent 21 is arranged on the graft 22 (both the stent 21 and the graft 22 are present). On the other hand, the non-stented region A2 is located on the proximal side of the stent graft 2 (the proximal side of the stented region A1), and is a region where the stent 21 is not placed on the graft 22 (only the graft 22 exists). is. The axial length of the stent-arranged region A1 is, for example, about 130 to 250 mm, and the axial length of the non-stent-arranged region A2 is, for example, about 20 mm.

In addition, in the examples shown in FIGS. 1 and 3, a portion of the stent graft 2 is provided with a window 20 in which at least the graft 22 of the graft 22 and the stent 21 is not arranged. Specifically, in this example, a portion of the stent placement region A1 is provided with a window 20 in which the graft 22 is not placed (the stent 21 is exposed to the outside from the graft 22). In the example shown in FIG. 3, the window 20 has a substantially rectangular shape with a long axis along the axial direction (Z-axis direction) of the stent graft 2 . The length of the window portion 20 in the major axis direction is, for example, about 50 to 100 mm, and the length of the window portion 20 in the minor axis direction (the width along the circumferential direction of the stent graft 2) is, for example, The length is about 30 to 50% of the outer peripheral length of the stent graft 2 . The length from the end of the window 20 on the side of the non-stented region A2 to the boundary position between the non-stented region A1 and the non-stented region A2 is, for example, about 20 mm. On the other hand, the length from the end of the window 20 opposite to the non-stented region A2 to the end of the stent graft 2 is, for example, about 60 to 150 mm.

The graft 22 is connected to the stent 21 by means of sewing, adhesion, welding, or the like. In this case, the graft 22 covers and connects the stent 21 so as not to affect the expansion and contraction of the stent 21 . Note that such connecting portions between the graft 22 and the stent 21 are appropriately provided, for example, at both end portions or an intermediate portion of the stent 21 .

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 graft 2 in a diameter-reduced state in the distal region of the delivery shaft 11 . Specifically, in this example, as shown in Figs. In a sideways orientation the stent graft 2 is adapted to be retained within the cover 3 . The outer diameter of the cover 3 is, for example, approximately 5.0 to 20.0 mm, preferably approximately 7.5 to 18.0 mm, and a preferred example is 13.0 mm.

Such a cover 3 is composed of a soft cover in this example. By covering the stent graft 2 in a diameter-reduced state with a soft cover, the stent graft 2 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 and 2, the cover 3 of the present embodiment includes two types of covers (covers 31 , 32). The cover 31 is arranged on the base end side of the cover 32 along the axial direction, and the cover 32 is arranged on the distal end side of the cover 31 along the axial direction.

Note that the cover 31 corresponds to a specific example of the "first cover" in the present invention. Also, the cover 32 corresponds to a specific example of the "second cover" in the present invention.

As shown in FIGS. 1 and 2, the cover 31 has a cylindrical structure extending along the axial direction. The axial length of the cover 31 is, for example, about 30 to 150 mm.

The cover 32 has a two-layer structure (double structure) having an inner layer portion 321 and an outer layer portion 322, as shown in FIGS. In other words, the cover 32 has a tubular outer layer portion 322 and an inner layer portion 321 located on the inner peripheral side of the outer layer portion 322 . In the example shown in FIG. 2 , the outer layer portion 322 is positioned on the outer peripheral side of the delivery shaft 11 and the inner layer portion 321 is positioned on the inner peripheral side of the delivery shaft 11 . Further, the cover 32 is provided with a folded portion 323 which is a portion that connects (connects) the outer layer portion 322 and the inner layer portion 321 at the distal end side of the delivery shaft 11 (see FIGS. 1 and 2). reference). Specifically, the cover 32 is formed by folding a cylindrical tube member inward, and the folded portion corresponds to the inner layer portion 321 . 1 and 2, the proximal side of the inner layer portion 321 extends to the proximal side of the catheter 1 through the inside of the delivery shaft 11. As shown in FIGS. Specifically, as shown in FIG. 1 , the proximal side of the inner layer portion 321 is inserted through the insides of the delivery shaft 11 and the handle 12 , respectively, and protrudes from the proximal side of the handle 12 .

Further, as shown in FIG. 2, the stent graft 2 is placed between the cover 31 and the delivery shaft 11 (between the layers) and between the outer layer portion 322 of the cover 32 and the delivery shaft 11 in the diameter-reduced state described above. , is held (see arrow P0). In the example shown in FIGS. 1 and 2, in the stent graft 2 in such a diameter-reduced state, the tip of the window 20 is positioned near the boundary Pb between the

covers

31 and 32. . In other words, the stent graft 2 is held in a diameter-reduced state within these

covers

31 and 32 so that the tip of the window 20 in the stent graft 2 is positioned near the boundary Pb between the

covers

31 and 32. It's like

The cover 31 and the cover 32 (the outer layer portion 322, the inner layer portion 321, the folded portion 323, etc.) are each 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, fluorine resin 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. Incidentally, the members constituting the cover 3 (covers 31 and 32) described above may be those which are manufactured in advance into a tubular shape using the above-mentioned materials, or those which are flattened into a tubular shape, or those which are formed into a tubular shape. The thing which consists of a combination, etc. are mentioned.

With such a configuration of the cover 3 (covers 31 and 32), the stent graft 2 is expanded by pulling the

covers

31 and 32, which will be described later. The details of the operation for expanding the stent graft 2 (the method of placing the stent graft 2 during treatment) will be described later (FIG. 6).

[Operation and action/effect]
(A. Basic operation)
The treatment device 4 of the present embodiment is used, for example, for treatment of arterial dissection and 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 FIG. 4, an outline of a treatment method for arterial dissection (aneurysm) using this OSG method (a method of using the treatment device 4) will be described.

FIG. 4 is a schematic diagram showing an example of how to use the treatment device 4 during such treatment. Here, it is assumed that the artery 9 (thoracic aorta), which is the blood vessel to be treated, includes the distal arch aorta (the portion of the arch bifurcation 9B shown in FIG. 4) and the proximal descending aorta. , will be described as an example.

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 4 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, for example, as shown in FIGS. 1 and 2, 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 in an arterial dissection state, for example, as shown in FIG. A new lumen (false lumen 9F) is present as a result of tearing of the inner wall of the blood vessel. 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 9F. 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 9T without being mistakenly inserted into the false lumen 9F. 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). As described above, since the guide wire is surely inserted into the true lumen 9T, by inserting the catheter 1 into the artery 9 along the guide wire, the catheter 1 can also be reliably inserted. is inserted into the true lumen 9T. That is, even in the case of arterial dissection, the risk of the catheter 1 being inserted into the false lumen 9F is avoided.

Next, as shown in FIG. 4, for example, the treatment device 4 is used to allow the stent graft 2 to reach a site in the artery 9 beyond the site to be treated (near the aneurysm formation 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 (an operation of pulling toward the proximal end) with respect to the

covers

31 and 32, which will be described later. Then, the

covers

31 and 32 are 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 .

Thereby, the stent graft 2 is fixed to the inner wall of the artery 9 as shown in FIG. 4, for example. As a result, the lumen of artery 9 near the site of aneurysm formation is dilated and retained. Thereafter, the proximal end side of the stent graft 2 (the graft 22 in the non-stented region A2) and the artery 9 (vessel of the patient) are sutured to form an anastomosis. Further, as shown in FIG. 4, for example, an artificial blood vessel 90 other than the stent graft 2 may be anastomosed with the anastomosis portion, if necessary.

In this way, the inner periphery of the aneurysm is covered with the stent graft 2, allowing blood flow to pass through the stent graft 2 (see arrow P91 in FIG. 4) and flow into the cleft in the inner wall of the blood vessel (false lumen 9F). As a result of blocking the inflow of blood to the aneurysm, blood pressure and the like cease to act on the aneurysm. Therefore, enlargement of the aneurysm diameter and rupture of the blood vessel can be prevented.

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, although the details will be described later, in this embodiment, as shown in FIG. Blood flows through the gaps between the stents 21 in the windows 20 (see arrow P92). 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)
Next, with reference to FIGS. 5 and 6 in addition to FIGS. 1 to 4, the action and effect of the cover 3 (covers 31 and 32) of the present embodiment will be described in detail while comparing with a comparative example. .

FIG. 5 schematically shows an example of a placement method of the stent graft 2 when using a therapeutic device (therapeutic device 104) according to a comparative example. Moreover, FIG. 6 schematically shows an example of a placement method of the stent graft 2 in the case of using the therapeutic device 4 of the present embodiment. 5 and 6 also show the insertion direction (arrow P8) of the catheter 1 into the artery 9 described above with reference to FIG.

(B-1. Placement method of comparative example)
First, in the therapeutic device 104 of the comparative example shown in FIG. 5, the stent graft 2 is placed in the blood vessel (artery 9) to be treated as follows. In the treatment apparatus 104 of this comparative example, instead of the cover 3 composed of the two types of

covers

31 and 32 in the treatment apparatus 4 of the embodiment, a single cover 103 is provided. It is a thing.

In this comparative example, first, as shown in FIG. 5A, for example, the operator of the catheter 1 pulls the proximal end of the cover 103 toward the proximal end of the delivery shaft 11 (see arrow P101). . By performing such a pulling operation on the cover 103, the stent graft 2 in a diameter-reduced state is pulled by the self-expanding force of the stent 21, as shown in FIGS. It expands sequentially from the inside and expands in diameter (see arrow P102). 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, as shown in FIG. 5(C), the entire stent graft 2 is finally deployed and expanded in diameter.

However, in the comparative example using the therapeutic device 104 having such a cover 103, when the diameter-reduced stent graft 2 is deployed from within the cover 103 and expanded in diameter by the pulling operation described above, the following problems occur. Problems can arise. That is, when the diameter of the stent graft 2 expands, the stent graft 2 also extends along its axial direction (Z-axis direction). (See arrow m shown in FIG. 5(C)). Further, if such deviation of the indwelling position of the stent graft 2 becomes large, there is a possibility that the convenience will be impaired in the treatment of arterial dissection or the like using the OSG method.

(B-2. Placement method according to the present embodiment)
On the other hand, in the treatment apparatus 4 of the present embodiment shown in FIG. 6, the above-described two types of

covers

31 and 32 are used to perform Placement of the stent graft 2 is performed.

First, as shown in FIG. 6A, for example, the operator of the catheter 1 pulls the proximal side of the inner layer 321 of the cover 32 toward the proximal direction of the catheter 1 (second pulling). operation) is performed (see arrow P12). By performing such a pulling operation on the inner layer portion 321 of the cover 32, the outer layer portion 322 of the cover 32 is pulled into the delivery shaft 11 via the folded portion 323 (see arrow P120), and the catheter 1 is pulled. It will be gradually pulled proximally.

Therefore, for example, as shown in FIG. 6(B), the stent graft 2 in a diameter-reduced state is sequentially expanded from within the cover 32 by the self-expanding force of the stent 21 and expands in diameter (see arrow P2). Specifically, the stent graft 2 is gradually deployed from the distal end side to the proximal end side (near the boundary Pb between the

covers

31 and 32 in this example) and expands in diameter.

Subsequently, as shown in FIG. 6B, for example, the operator of the catheter 1 pulls the proximal side of the cover 31 toward the proximal end of the delivery shaft 11 (first pulling operation). (see arrow P11). That is, in the example shown in FIG. 6, the pulling operation (first pulling operation) for the cover 31 is started after the above-described pulling operation (second pulling operation) for the cover 32 is started.

By also performing such a pulling operation on the cover 31, as shown in FIGS. They are also successively expanded from inside the cover 31 to expand in diameter (see arrow P2). Specifically, in this example, the portion of the stent graft 2 on the proximal side (the proximal side of the boundary Pb described above) is gradually deployed from the distal side toward the proximal side and expands in diameter. .

As a result, for example, as shown in FIG. 6(D), the entire stent graft 2 (the entire area including the window 20) is finally deployed and expanded in diameter.

(B-3. Action and effect)
Thus, in the therapeutic device 4 of the present embodiment, the cover 3 for holding the stent graft 2 in a diameter-reduced state in the distal end region of the delivery shaft 11 includes two types of covers (the proximal cover 31 and the distal end cover 31). It is axially separated on the side cover 32). The stent graft 2 is held in a diameter-reduced state between the cover 31 and the delivery shaft 11 and between the outer layer portion 322 of the cover 32 and the delivery shaft 11 .

As a result, in this embodiment, for example, when the stent graft 2 is placed in the affected area of the artery 9 or the like, the treatment is as follows. That is, during such treatment, an operation of pulling the proximal side of the cover 31 toward the proximal direction of the delivery shaft 11 and pulling the proximal side of the inner layer portion 321 of the cover 32 toward the proximal direction of the catheter 1 is performed. When the diameter-reduced stent graft 2 is expanded from the

covers

31 and 32 by (pulling operation), the following occurs. That is, the stent graft is pulled along the axial direction toward the vicinity of the boundary Pb between the covers 31 and 32 (near the intermediate position of the stent graft 2). As a result, when the diameter-expanded stent graft 2 is left in the patient's body, in the present embodiment, unlike the comparative example, displacement of the stent graft 2 (positional displacement in the axial direction) is suppressed. be. Therefore, in the present embodiment, by performing treatment using the treatment apparatus 4 having such two types of

covers

31 and 32, it is possible to improve the convenience of the treatment described above. .

Further, in the present embodiment, by performing the above-described pulling operation (first pulling operation) on the cover 31 and the above-described pulling operation (second pulling operation) on the inner layer portion 321 of the cover 32, The diameter-reduced stent graft 2 is expanded from the

covers

31 and 32 to expand its diameter. By performing the first and second pulling operations as the pulling operations in this way, when the diameter-reduced stent graft 2 is deployed from the

covers

31 and 32 and expanded in diameter, the above-mentioned In this way, it is possible to suppress the displacement of the indwelling position of the stent graft 2 .

Furthermore, in the present embodiment, the above-described first pulling operation is started after the above-described second pulling operation is started, so that the diameter-reduced stent graft 2 is pulled from inside the

covers

31 and 32, respectively. They are deployed and expanded in this order. As a result, the displacement of the indwelling position of the stent graft 2 described above can be more easily suppressed, and as a result, convenience during treatment can be further improved.

In addition, in the present embodiment, the stent graft 2 is partially provided with the window 20 in which at least the graft 22 out of the graft 22 and the stent 21 is not arranged. That is, for example, as shown in FIG. 4 described above, the window portion 20 (in the example of FIG. 4, the window portion 20), blood flows (see arrow P92 in FIG. 4). In other words, in addition to the inside of the blood vessel (artery 9, etc.) in which the stent graft 2 is indwelled (see arrow P91 in FIG. 4), blood can also flow through the window 20 to the arch branch 9B. become. 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.

In addition, in the present embodiment, in the stent graft 2 in a diameter-reduced state, the tip of the window portion 20 is positioned near the boundary Pb between the

covers

31 and 32, so the following is the case. That is, when the diameter-reduced stent graft 2 is deployed from within the

covers

31 and 32 and expanded in diameter by the above-described pulling operations (the first and second pulling operations), The stent graft 2 will be pulled. Therefore, since the tip of the window 20 is positioned near the boundary Pb, the position of the window 20 may shift (position in the axial direction) when the expanded stent graft 2 is placed in the patient's body. deviation) is suppressed. As a result, it is possible to further improve the convenience of treatment.

<2. Variation>
Next, a modification of the above embodiment will be described. In addition, the same code|symbol is attached|subjected to the same thing as the component in embodiment, and description is abbreviate|omitted suitably.

[Constitution]
FIG. 7 schematically shows a configuration example of a stent graft (stent graft 2A according to a modification) applied to a therapeutic device according to a modification. It should be noted that, like the therapeutic device 4 described in the embodiment, the therapeutic device of this modified example is also a device that is used, for example, in the treatment of arterial dissection using the OSG method.

The treatment apparatus of this modification is provided with a stent graft 2A described below instead of the stent graft 2 in the treatment apparatus 4 of the embodiment, and has other configurations (each configuration of the catheter 1 and the cover 3). The same is true for

As shown in FIG. 7, the stent graft 2A of this modification corresponds to the stent of the embodiment (see FIG. 3, etc.) in which the window 20 is not provided in the stent placement region A1. Other configurations are the same. That is, in this stent graft 2A, unlike the stent graft 2, the stent 21 is not exposed from the graft 22 in the entire area of the stent arrangement area A1.

[Action/effect]
Also in this modified example having such a configuration, basically, it is possible to obtain the same effect by the same operation as the embodiment. That is, in this modified example as well, by performing treatment using the treatment apparatus having the two types of

covers

31 and 32 described above, it is possible to improve the convenience of the treatment described above.

<3. Other modified examples>
Although the present invention has been described above with reference to the embodiments and modifications, the present invention is not limited to these embodiments and the like, and various modifications are possible.

For example, the configuration (shape, arrangement position, size, number, material, etc.) of each member described in the above embodiments and the like is not limited, and other shapes, arrangement positions, sizes, number, materials, etc. may be used. good. Specifically, in the above-described embodiment and the like, specific configuration examples of the

covers

31 and 32 have been described. etc.) may be changed to other shapes, positions, sizes, numbers, materials, and the like. More specifically, for example, the cover 31 may have a two-layer structure similar to the cover 32, having an outer layer portion, an inner layer portion, and a folded portion. Also, in the above-described embodiment and the like, the case where the ends of the

covers

31 and 32 do not overlap each other along the axial direction has been described as an example, but the present invention is not limited to this example. That is, if the

covers

31 and 32 are arranged apart from each other along the axial direction, the ends of these

covers

31 and 32 may partially overlap along the axial direction. .

In addition, in the above-described embodiment and the like, the case where the inner layer portion 321 and the outer layer portion 322 of the cover 32 are integrated with each other via the folded portion 323 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.

Furthermore, in the above-described embodiment and the like, the case where the distal end of the window portion 20 is positioned near the boundary Pb between the

covers

31 and 32 in the stent graft in a diameter-reduced state has been described as an example. is not limited. That is, for example, the diameter-reduced stent graft may be arranged so that the tip of the window portion 20 is not positioned near such a boundary Pb. Further, in the above-described embodiment and the like, an example in which the window portion 20 in which the graft 22 is not arranged is provided in a part of the stent graft 2 (stent arrangement region A1) has been described. Examples are not limited. That is, for example, a window portion in which neither the graft 22 nor the stent 21 is arranged may be provided in a part of the stent arrangement region A1 or the stent non-arrangement region A2.

In addition, in the above-described embodiments and the like, the stent graft is provided with one stent-arranged region arranged on the distal end side within the cover and a non-stent-arranged region arranged on the proximal end side within the cover. Although an example of a case in which the number of That is, for example, another non-stented region may be further provided on the distal end side of the stented region of the stent graft. In other words, in the stent graft, the stent-placed region may be sandwiched between two non-stented regions.

In addition, in the above-described embodiments and the like, the stent graft placement method using the therapeutic device has been described with specific examples. Not limited. Specifically, for example, in the above embodiment and the like, after the pulling operation (second pulling operation) on the proximal side of the inner layer portion 321 of the cover 32 is started, the pulling operation (second pulling operation) on the proximal side of the cover 31 is performed. 1 pulling operation) has been described, but the present invention 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 second pulling operation is performed after the first pulling operation is started. An operation may be initiated.

Furthermore, in the above embodiments and the like, 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 embodiments and the like, 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 are taken as examples. Although described, 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 stent graft comprising a tubular graft and a stent;
first and second covers spaced apart from each other along the axial direction for holding the stent graft in a reduced diameter state at the distal end region of the shaft;
The first cover is arranged on the proximal end side of the second cover along the axial direction,
The second 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 outer layer portion and the shaft and extending to the proximal end side of the catheter through the inside of the shaft;
a folded portion that connects the outer layer portion and the inner layer portion on the distal end side of the shaft;
wherein the stent graft is held in the reduced diameter state between the first cover and the shaft and between the outer layer of the second cover and the shaft, respectively. .
a first pulling operation, which is an operation of pulling the proximal side of the first cover toward the proximal direction of the shaft;
a second pulling operation, which is an operation of pulling the proximal side of the inner layer portion of the second cover in the proximal direction of the catheter;
are performed,
2. The treatment device of claim 1, wherein the stent graft in the reduced diameter state is deployed from within the first and second covers, respectively, to expand.
By starting the first pulling operation after the second pulling operation is started,
3. The therapeutic device of claim 2, wherein the stent-graft in the reduced diameter state is adapted to be deployed and expanded from within the second and first covers, respectively, in that order.
The treatment apparatus according to any one of claims 1 to 3, wherein a portion of the stent graft is provided with a window portion in which at least the graft of the graft and the stent is not arranged.
5. The treatment apparatus according to claim 4, wherein in the stent graft in the diameter-reduced state, the tip of the window portion is positioned near the boundary between the first and second covers.