JP6832111B2 - Stent graft, stent graft set, and stent graft indwelling device - Google Patents

Description

The present invention relates to a stent graft, a stent graft set which is a combination of the stent graft and another stent graft, and a stent graft indwelling device for indwelling the stent graft in a blood vessel.

Conventionally, stent grafts used for the treatment of aortic aneurysm and aortic dissection occurring in the aorta have been known. A stent graft generally has a tubular shape that defines a flow path through which blood flow can pass, and has a skeleton (stent) capable of contracting inward in the radial direction and expanding in the outward direction in the radial direction, and a skeleton thereof. It is provided with a film portion (graft) provided along the portion. The stent graft is carried to the affected area (where the aortic aneurysm or the like is occurring) in a contracted state in which the skeleton is contracted, and then deformed into an expanded state in which the skeleton is expanded. As a result, the stent graft reinforces the blood vessels, blocks the inflow of blood into the aortic aneurysm and the like, and suppresses the expansion (growth) of the aortic aneurysm and the like.

For example, one of the conventional stent grafts (hereinafter referred to as "conventional stent graft") maintains the blood flow from the main blood vessel to the bifurcated blood vessel while blocking the blood inflow to the aortic aneurysm or the like generated in the main blood vessel. Therefore, a conical trapezoidal opening (side opening) protruding toward the bifurcated blood vessel is provided on the side surface of the stent graft to be placed in the main blood vessel. Conventional stent grafts are provided with a skeleton (for example, a spiral stent extending from the base end of the side opening toward the opening) at the side opening to push the side opening toward a bifurcated blood vessel at the time of placement. (Expand) (see, for example, Patent Document 1).

Japanese Patent No. 5789867

As described above, the conventional stent graft is adapted to insert the lateral opening into the vascular opening of the bifurcated blood vessel by pushing the truncated cone-shaped lateral opening toward the bifurcated blood vessel at the time of indwelling. However, due to the function of such a lateral opening, the conventional stent graft needs to be placed with high positional accuracy so that the positional deviation between the lateral opening and the vascular opening of the bifurcated vessel is as small as possible. In other words, in the conventional stent graft, when the position accuracy is insufficient at the time of placement, the lateral opening contacts (interferes) with the inner wall of the main blood vessel and is not sufficiently inserted into the vascular opening of the bifurcated blood vessel (the lateral opening is sufficient). May not open).

On the other hand, the placement of the stent graft is usually performed based on a fluoroscopic image (two-dimensional plane image) obtained by an X-ray fluoroscope. Therefore, it is generally difficult to place the conventional stent graft so that the lateral openings of the conventional stent graft are sufficiently aligned with the bifurcated blood vessels (particularly so that they are sufficiently aligned in the rotational direction around the axis of the conventional stent graft). Yes, very advanced technology will be required for such an arrangement.

However, from the viewpoint of facilitating the placement of the stent graft as much as possible, the accuracy of alignment (position accuracy at the time of placement) between the branched blood vessel and the truncated cone-shaped side opening protruding toward the branched blood vessel is tentatively inadequate. Even if it is sufficient, it is desirable that the conventional stent graft is configured so that the function as the stent graft is not impaired.

The present invention has been made in view of the above circumstances, and an object of the present invention is a stent graft capable of sufficiently exerting a function as a stent graft even if the position accuracy at the time of placement is insufficient. It is an object of the present invention to provide a stent graft set which is a combination of a stent graft and another stent graft, and a stent graft indwelling device for indwelling the stent graft in a blood vessel.

In order to achieve the above-mentioned object, the "stent graft" according to the present invention is characterized by the following (1) to (3).
(1)
A tubular stent graft that defines a flow path through which blood flows.
A skeleton that can contract inward in the radial direction and expand outward in the radial direction,
A film portion provided along the skeleton portion is provided.
It is possible to deform from the contracted state in which the skeleton portion is contracted to the expanded state in which the skeleton portion is expanded and the flow path is defined by the film portion.
Wherein in the expanded state, see recessed portion is radially inward of the outer peripheral surface is formed a recess having a planar bottom surface, a cylindrical shape extending radially outward from a predetermined position of the bottom surface of the recess, the blood flow is closed and the cylindrical opening capable of passing, and
The tubular opening
To have the opening facing the changeable flexibility of the cylindrical opening by the blood flow through the cylindrical opening diverted from the flow channel,
Must be a stent graft.
( 2 )
In the stent graft described in (1) above
The entire tubular opening
In the expanded state, it exists inside the recessed space defined by the recesses.
Must be a stent graft.
( 3 )
In the stent graft according to (1) or (2) above.
The skeleton
It does not exist near the connection point between the tubular opening and the recess.
Must be a stent graft.

According to the stent graft having the configuration of (1) above, a concave portion recessed inward in the radial direction is formed on the outer peripheral surface of the stent graft, and a tubular shape extending outward in the radial direction is formed in the concave portion to allow blood flow. It is provided with a passable tubular opening. Therefore, when the stent graft of this configuration is placed at the bifurcation position between the main blood vessel and the bifurcated blood vessel, even if the tubular opening does not sufficiently match the bifurcated blood vessel, the tubular opening is in the recess. Can be opened (extended outward in the radial direction), so that the tolerance for misalignment is larger than that of the conventional stent graft. That is, the stent graft having this configuration is more likely to open a tubular opening during indwelling while maintaining the function as a stent graft (for example, ensuring blood flow to a bifurcated blood vessel) as compared with a conventional stent graft.

Therefore, the stent graft having this configuration can sufficiently exert the function as a stent graft as compared with the conventional stent graft, even if the position accuracy at the time of placement is insufficient.

By using the stent graft having the above configuration, it is possible to treat an aortic aneurysm or the like generated in the vicinity of the bifurcation position between the main blood vessel and the bifurcated blood vessel. Specifically, after placing a stent graft in the main blood vessel, if the tubular opening of the stent graft and another stent graft placed in the bifurcated blood vessel (so-called branch stent graft) are connected, it will occur near the bifurcation position. It can block the inflow of blood into aortic aneurysms and the like. Since the tubular opening of the stent graft having the above configuration is easy to open as described above, it can be easily connected to another stent graft as compared with the conventional stent graft.

Furthermore, according to the stent graft of the above configuration (1), the tubular opening, the main vessel degree opening direction is deformable tubular opening by the blood flow diverted from (channel) Flexibility (Flexibility ). Therefore, even if the tubular opening does not sufficiently match the bifurcated blood vessel, the blood flow from the main blood vessel to the bifurcated blood vessel naturally guides the tubular opening toward the bifurcated blood vessel. Become. Therefore, the ease of opening the tubular opening is improved. Further, since the tubular opening has such flexibility, the adhesion between the two is improved when the tubular opening is connected to another stent graft (branch stent graft).

The tubular opening may be formed by a coating portion constituting the stent graft (so as to extend the coating portion), and an independent member other than the coating portion may be connected (for example, adhered) to the recess. It may be composed of. Further, the tubular opening is provided along the opening end as a member separate from the skeleton portion (stent) described above in order to prevent obstruction of the opening end (the outermost end portion in the radial direction of the stent graft). It may have a ring-shaped holder. Similarly, the tubular opening is provided along the proximal end as a member separate from the skeleton portion (stent) in order to prevent obstruction of the proximal end (the connection point between the tubular opening and the recess). It may have a ring-shaped retainer.

According to the stent graft having the above configuration (2 ), the entire tubular opening exists inside the recessed space due to the recess. In other words, the length of the recess from the connection point between the recess and the tubular opening (the base end of the tubular opening) to the opening end of the tubular opening (ie, the height of the tubular opening) The depth is large. Therefore, even if the tubular opening does not sufficiently match the bifurcated blood vessel, the opening end of the tubular opening does not come into contact (interfere) with the inner wall of the main blood vessel or the like. Therefore, the ease of opening the tubular opening is further improved.

By the way, the above-mentioned "recessed space" represents a space sandwiched between the surface of the stent graft that defines the recess and the surface (virtual surface) of the stent graft when it is assumed that the recess does not exist. In other words, the above-mentioned "recessed space" represents a space sandwiched between the surface of the stent graft that defines the recess and the inner wall surface of the blood vessel when the stent graft is placed in the blood vessel.

According to the stent graft having the above configuration (3 ), there is no skeleton portion in the vicinity of the connection point (base end of the tubular opening) between the tubular opening and the recess. Therefore, the degree of freedom in the opening direction of the tubular opening (the flexibility of the tubular opening described above, flexibility) is further improved. Therefore, the ease of opening the tubular opening is further improved.

By the way, the above-mentioned "near the connection point" represents, for example, a range in which a recess (recessed space) can be maintained against a pressure toward the outside in the radial direction due to a blood flow passing through a main blood vessel. For example, if the recess (recess space) can be maintained by the skeleton portion around the recess (outside the recess), the skeleton portion may not be present in the entire recess.

Further, in order to achieve the above-mentioned object, the "stent graft set" according to the present invention is characterized by the following (4 ) and ( 5).
( 4 )
The first stent graft, which is the stent graft according to any one of the above (1) to ( 3),
A tubular second stent graft that can be connected to the tubular opening of the first stent graft.
Must be a stent graft set.
( 5 )
In the stent graft set described in (4) above,
The tubular opening
It has a reduced diameter shape in which the opening area becomes smaller as the distance from the connection point between the tubular opening and the recess is increased.
The second stent graft
In the vicinity of the opening end, it has an enlarged diameter shape in which the opening area increases as it approaches the opening end.
The tubular opening of the first stent graft and the vicinity of the opening end of the second stent graft are in close contact with each other.
Must be a stent graft set.

According to the stent graft set having the configuration of ( 4 ) above, the second stent graft (branch stent graft) is connected to the tubular opening of the first stent graft (main stent graft) having the characteristics of (1) to (3) above. By doing so, blood inflow to an aortic aneurysm or the like generated in the vicinity of the bifurcation position between the main blood vessel and the bifurcated blood vessel is blocked, and such an aortic aneurysm or the like can be treated. As described in (1) to ( 3 ) above, the first stent graft is easily connected to the second stent graft as compared with the conventional stent graft because the tubular opening is easily opened.

According to the stent graft set having the above configuration (5 ), the reduced diameter portion of the tubular opening of the first stent graft and the enlarged diameter portion near the opening end of the second stent graft are in close contact with each other. As a result, the contact area between the two can be increased and the liquidtightness between the two can be improved as compared with the case where such a reduced diameter portion and an enlarged diameter portion do not exist. Therefore, it is possible to suppress blood leakage (so-called end leak) between the first stent graft and the second stent graft.

By the way, the above-mentioned "near the opening end" represents, for example, a range to which the above-mentioned liquidtightness (suppression of end leakage) can be realized.

Further, in order to achieve the above-mentioned object, the "stent graft indwelling device" according to the present invention is characterized by the following (6).
( 6 )
A stent graft indwelling device for indwelling a stent graft in a blood vessel.
The stent graft according to any one of (1) to ( 3) above,
A container in which the stent graft is housed in the contracted state and
An operating tool that releases the stent graft from the container and transforms it into the expanded state.
With,
Must be a stent graft placement device.

According to the stent graft indwelling device having the configuration of (6 ) above, it is possible to provide a set of instruments for indwelling a stent graft having the characteristics of (1) to (3) above in a blood vessel.

According to the present invention, a stent graft capable of sufficiently exerting a function as a stent graft even if the position accuracy at the time of placement is insufficient, a stent graft set which is a combination of the stent graft and another stent graft, and a stent graft set. , A stent graft indwelling device for indwelling the stent graft in a blood vessel can be provided.

The present invention has been briefly described above. Further, the details of the present invention will be further clarified by reading through the embodiments for carrying out the invention described below (hereinafter referred to as "embodiments") with reference to the accompanying drawings.

FIG. 1 (a) is a diagram schematically showing substantially the entire aorta of the human body (from the ascending aorta to the common iliac artery), and FIG. 1 (b) shows the thoracic aorta which is a part of the aorta of the human body. It is an enlarged diagram schematically shown. FIG. 2A is a perspective view showing a main stent graft and a branch stent graft constituting the stent graft set according to the embodiment of the present invention, and FIG. 2B is a plan view of the main stent graft. 2 (c) is a cross-sectional view taken along the line AA of FIG. 2 (b). FIG. 3A is a diagram showing each component constituting the stent graft indwelling device according to the embodiment of the present invention, and FIG. 3B is a diagram showing the entire stent graft indwelling apparatus in which each component is assembled. .. FIG. 4 is a diagram showing a state of deformation of the tubular opening when the main stent graft is folded. 5 (a) to 5 (f) are a series of diagrams for explaining a procedure for placing the main stent graft in the affected area in the aorta using the stent graft indwelling device. FIG. 6 (a) is a diagram showing an example of a state in which the main stent graft is placed in the aorta with the positions of the tubular opening of the main stent graft and the bifurcation artery coincided with each other, and FIG. 6 (b) is a diagram. It is a figure which shows an example of the state in which the main stent graft is indwelled in the aorta in the state where the position shift occurs between the tubular opening of the main stent graft and the bifurcation artery. FIG. 7A is a diagram showing a state in which a branch stent graft is connected to the tubular opening shown in FIG. 6A, and FIG. 7B is a diagram showing the connection of the branch stent graft in FIG. 7A. It is sectional drawing which shows the part enlarged. 8 (a) is a diagram showing a modified example of the main stent graft according to the embodiment of the present invention shown in FIG. 2 (a), and FIG. 8 (b) is a diagram showing a modified example of the main stent graft shown in FIG. 2 (a). It is a figure which shows the other modification of the main stent graft which concerns on embodiment of the invention. FIG. 9 is a diagram corresponding to FIG. 7 (b) in a modified example of the stent graft set according to the embodiment of the present invention. FIG. 10 is a diagram corresponding to FIG. 7A in a modified example of the stent graft set according to the embodiment of the present invention.

<Aorta and stent graft>
Hereinafter, as a preparation for explaining the embodiment of the present invention, first, with reference to FIG. 1, the structure of the aorta of the human body and the stent graft used for the treatment of aortic aneurysm and the like will be briefly described.

As shown in FIG. 1 (a), the aorta of the human body is an artery that ascends from the left ventricle of the heart, bends in an arch shape, and then descends to the common iliac artery at the bifurcation of the abdominal aorta. It is an artery that is the source of blood circulation to the whole body. A state in which a part of the blood vessel wall constituting the aorta is swollen like a hump is called an "aortic aneurysm". On the other hand, a state in which the media is peeled off (dissociated) by blood flowing out through a fissure or the like formed in the intima of the blood vessel wall constituting the aorta is called "aortic dissection". These aortic aneurysms and the like can occur in various parts of the aorta. Aortic aneurysm and the like are serious diseases that can lead to death if left untreated.

As a surgical treatment method for aortic aneurysm and the like, so-called "artificial blood vessel replacement" is well known, in which the blood vessels in the affected area where the aortic aneurysm or the like is formed are replaced with artificial blood vessels. On the other hand, in recent years, a method called "stent graft interpolation" or the like has attracted attention. This method is a method using a stent graft indwelling device including a stent graft whose diameter is maintained inside the sheath. Specifically, in this method, for example, a small incision is made in the base of the thigh called the inguinal region, a sheath is inserted into the aorta, and the stent graft is exposed and deployed from the tip of the sheath in the affected area, and the stent graft is placed in the affected area. This is a method of preventing rupture of an aortic aneurysm or the like. Stent graft interpolation is a minimally invasive treatment method that does not require thoracotomy or laparotomy as compared with artificial blood vessel replacement surgery.

As shown in FIG. 1 (b), among the aortas, especially in the thoracic aorta, there are three bifurcated arteries (branched blood vessels) branching from the aorta (main blood vessel). The stent graft according to the embodiment of the present invention can be used particularly for the treatment of an aortic aneurysm or the like occurring in the aorta in the vicinity of the bifurcation position between the aorta and the bifurcated artery. The stent graft according to the embodiment of the present invention can also be used for the treatment of aortic aneurysms and the like generated at other sites.

<Overall configuration>
Hereinafter, the stent graft 10 (main stent graft), the stent graft set, and the stent graft indwelling device 1 according to the embodiment of the present invention will be described with reference to FIGS. 2 to 7.

Hereinafter, for convenience, the main stent graft will be simply referred to as a "main graft", and the branch stent graft will be simply referred to as a "branch graft".

As shown in FIG. 2A, the stent graft set according to the embodiment of the present invention has a main graft 10 and a branch graft 20. The main graft 10 is placed in the affected part of the aorta (the place where the aortic aneurysm or the like occurs), and the branch graft 20 is placed in the branch artery branching from the aorta in the vicinity of the affected part.

<Main graft>
First, the main graft 10 will be described. As shown in FIGS. 2 (a) to 2 (c), the main graft 10 has a tubular shape that defines a tubular flow path through which blood flow can pass, and the skeleton portion 11 (stent) and the coating portion 12 have a tubular shape. Has (graft). In this example, the main graft 10 has a linear tubular shape. However, the shape of the main graft 10 is not necessarily limited to a straight line, and may have a curved tube shape (for example, a shape corresponding to the shape of the patient's aortic arch) if necessary (FIG. 8 described later). See also). The main graft 10 may have a curved shape in which the placement location is assumed in advance before the placement, or may have a curved shape along the blood vessel shape after the placement.

The skeleton portion 11 is formed in a self-expanding wire mesh shape in which fine metal wires are folded back in a zigzag shape and formed into a tube shape, and the tubular flow path expands outward in the radial direction from a contracted state contracted inward in the radial direction. Can be transformed into the defined extended state. Examples of the material constituting the skeleton portion 11 include known metals or metal alloys typified by stainless steel, Ni—Ti alloys, titanium alloys and the like.

The film portion 12 is fixed to the skeleton portion 11 so as to cover the skeleton portion 11 along the skeleton portion 11, and defines the above-mentioned tubular flow path. The film portion 12 may cover the skeleton portion 11 from the outer circumference or the inner circumference, or may cover the skeleton portion 11 so as to sandwich the skeleton portion 11. Examples of the material of the film portion 12 include a fluororesin such as PTFE (polytetrafluoroethylene) and a polyester resin such as polyethylene terephthalate.

In the expanded state described above, the film portion 12 has a recess 13 in which a part of the outer peripheral surface is recessed inward in the radial direction, and a tubular opening 14 extending radially outward from a predetermined position in the recess 13. .. The tubular opening 14 is a portion to which the connection-side end 23 described later of the branch graft 20 is connected (see FIG. 7 described later).

Hereinafter, for convenience of explanation, as shown in FIG. 2C, the surface 13a of the main graft 10 that defines the recess 13 and the surface 13b of the main graft 10 when it is assumed that the recess 13 does not exist (FIG. 2C). The space sandwiched between () and the virtual surface (shown by a broken line) is called "recessed space 15". In other words, the recessed space 15 refers to a space sandwiched between the surface of the main graft 10 that defines the recess 13 and the inner wall surface of the aorta when the main graft 10 is placed in the aorta.

In this example, as shown in FIGS. 2A and 2C, the recess 13 has a flat bottom surface, and the tubular opening 14 is directed outward in the radial direction from the center position of the bottom surface. Is extending. The tubular opening 14 has a reduced diameter shape in which the opening area becomes smaller as the distance from the connection portion between the tubular opening 14 and the bottom surface of the recess 13 increases. Further, the entire tubular opening 14 exists inside the recessed space 15. In other words, it is more than the length from the connection point between the recess 13 and the tubular opening 14 (the base end of the tubular opening 14) to the opening end of the tubular opening 14 (height of the tubular opening 14). , The depth of the recess 13 is large.

The skeleton portion 11 does not exist on the bottom surface of the recess 13 and the tubular opening 14. Further, the tubular opening 14 is formed of the same material as the film portion 12. As a result, the tubular opening 14 has flexibility to the extent that the opening direction can be deformed by the blood flow branched from the aorta to the bifurcated artery.

The tubular opening 14 may be formed by the film portion 12 (so as to extend the film portion 12), and is formed as an independent member separate from the film portion 12, and the member is provided in the recess 13. It may be configured by connecting (eg, gluing) to the hole.

<Branch graft>
Next, the branch graft 20 will be described. As shown in FIG. 2A, the branch graft 20 also has a tubular shape that defines a tubular flow path through which blood flow can pass, like the main graft 10, and has a self-expanding skeleton portion 21 and a coating film. It has a part 22 and. Since the configurations of the skeleton portion 21 and the coating portion 22 are the same as those of the skeleton portion 11 and the coating portion 12 of the main graft 10, detailed description thereof will be omitted.

The end portion 23 (connecting side end portion) of the branch graft 20 on the side connected to the tubular opening portion 14 has a diameter-expanded shape in which the opening area increases as it approaches the opening end. As will be described later, the outer surface of the connecting side end 23 of the branch graft 20 having such an enlarged diameter shape and the inner surface of the tubular opening 14 of the main graft 10 having the reduced diameter shape described above are in close contact with each other. As such, the main graft 10 and the branch graft 20 are connected (see FIG. 7 described later).

<Stent graft indwelling device>
Next, a stent graft indwelling device 1 for indwelling the main graft 10 (and the branch graft 20) at a predetermined position in the blood vessel will be described with reference to FIG. Hereinafter, in FIG. 3, the right side is referred to as a base end side and the left side is referred to as a tip end side.

As shown in FIGS. 3 (a) and 3 (b), the stent graft indwelling device 1 is arranged inside the tubular first sheath 30 and the first sheath 30, and the inside of the first sheath 30 is the first sheath. A tubular second sheath 40 configured to be able to advance and retreat along the axial direction (longitudinal direction) of 30 and arranged inside the second sheath 40, and the inside of the second sheath 40 is the axial direction of the second sheath 40 ( A rod-shaped rod member 50 configured to be able to advance and retreat along the longitudinal direction) is provided.

Both the first sheath 30 and the second sheath 40 are made of a flexible material. As the flexible material, for example, a biocompatible synthetic resin (epolymer) selected from a fluororesin, a polyamide resin, a polyethylene resin, a polyvinyl chloride resin, and the like, and other materials are mixed with these resins. Examples thereof include the resin compound obtained, a multilayer structure made of these synthetic resins, and a composite of these synthetic resins and a metal wire.

On the base end side of the first sheath 30, a first sheath base portion 31 having an enlarged diameter shape in which the opening area increases as it approaches the base end is provided. Similarly, on the base end side of the second sheath 40, a second sheath base portion 41 having an enlarged diameter shape in which the opening area increases as it approaches the base end is provided.

As shown in FIG. 3A, the rod member 50 includes a rod main body 51, a holding portion 52 for holding the main graft 10 in a contracted state, and a tip provided at the tip side end of the rod member 50. It has a chip 53 and. The diameter of the holding portion 52 is smaller than that of the rod main body portion 51 by the thickness of the main graft 10 (or the branch graft 20). Therefore, the outer diameter of the main graft 10 (or branch graft 20) held by the holding portion 52 in the contracted state is substantially equal to the outer diameter of the rod main body portion 51. As can be understood from FIG. 3B, the maximum diameter of the tip tip 53 is substantially equal to the outer diameter of the first sheath 30.

Examples of the material constituting the rod body portion 51 and the holding portion 52 include various materials having appropriate hardness and flexibility, such as resin (plastic, elastomer) and metal. Examples of the material constituting the tip 53 include various materials having appropriate hardness and flexibility, such as a synthetic resin (elastomer) composed of a polyamide resin, a polyurethane resin, a polyvinyl chloride resin, and the like. Be done.

Although not shown, the rod body 51, the holding portion 52, and the tip tip 53 have, for example, a pore for a guide wire for inserting the guide wire, and a contracted stent graft 10 (and). The pores for the trigger wire for inserting the trigger wire for expanding the branch graft 20) in the affected portion are formed along the axial direction of the rod member 50 (longitudinal direction of the rod member 50).

Further, although detailed description is omitted, the tip tip 53 is provided with a locking groove (not shown) for locking the trigger wire. As a method for expanding the contracted stent graft 10 (or branch graft 20) in the affected area by using such a trigger wire and a tip, a known method can be used.

As shown in FIG. 3B, in a state where the main graft 10 is held inside the second sheath 40 by the holding portion 52 of the rod member 50 (that is, in a contracted state), as shown in FIG. , The tubular opening 14 is gradually folded inward in the radial direction from the connecting portion (base end) between the tubular opening 14 and the bottom surface of the recess 13. As a result, the tubular openings 14 are unlikely to overlap each other. Therefore, the tubular opening 14 can be easily folded. This is because the tubular opening 14 has the above-mentioned reduced diameter shape.

Next, the procedure for indwelling the main graft 10 in the affected part in the aorta using the stent graft indwelling device 1 shown in FIG. 3 (b) will be described with reference to FIG. FIG. 5 shows an example in which the main graft 10 is placed in a curved aortic arch in the thoracic aorta (see FIG. 1B).

First, as shown in FIGS. 5 (a) and 5 (b), a first guide wire (not shown) that has been previously inserted into a blood vessel from the descending aorta to the vicinity of the distal arch aorta is used. The entire stent graft placement device 1 is advanced so as to guide the sheath 30. Next, as shown in FIG. 5C, with the position of the first sheath 30 fixed, the second sheath is appropriately bent from the proximal arch aorta to the ascending aorta while appropriately bending the tip of the second sheath 40. Only advance 40. As a result, the tip of the stent graft indwelling device 1 can reach the position of an aortic aneurysm or the like generated in the proximal arch aorta or the ascending aorta.

After the tip of the stent graft indwelling device 1 reaches the affected area, as shown in FIG. 5D, the second sheath 40 is pulled out from the inside of the second sheath 40 with the position of the rod member 50 fixed. The main graft 10 is exposed. Further, as shown in FIG. 5 (e), the first sheath 30 is also pulled out to completely expose the main graft 10. The main graft 10 self-expands radially outward by being exposed to the outside from the second sheath 40.

Then, as shown in FIG. 5 (f), the above-mentioned trigger wire (not shown) is pulled to expand the tip portion of the main graft 10 radially outward, and the entire stent graft indwelling device 1 is pulled out together with the rod member 50. The placement of the main graft 10 is completed.

6 (a) and 6 (b) show an example of the case where the main graft 10 is placed in the aorta 60 near the bifurcation position between the aorta 60 and the bifurcation artery 70 as described above. In FIG. 6, for convenience, only one bifurcated artery 70 is shown.

FIG. 6A shows a state in which the tubular opening 14 of the main graft 10 and the bifurcation artery 70 are in the same position. In this way, when the positions of the tubular opening 14 and the bifurcation artery 70 match, the opening direction of the tubular opening 14 is branched by the blood flow (arrow in the figure) from the aorta 60 to the bifurcation artery 70. It is directed toward the ostium of the artery 70.

On the other hand, as shown in FIG. 6B, in a state where the tubular opening 14 of the main graft 10 and the bifurcation artery 70 are misaligned, the tubular opening 14 is from the aorta 60 to the bifurcation artery 70. Due to the blood flow toward (arrow in the figure), the opening direction of the tubular opening 14 is deformed toward the vascular opening of the bifurcated artery 70. This is because, as described above, the tubular opening 14 has flexibility. Further, as described above, since the entire tubular opening 14 exists inside the recessed space 15, even if there is a misalignment between the tubular opening 14 and the bifurcation artery 70, the tubular opening 14 The open end of 14 does not come into contact (interfere) with the inner wall surface of the aorta 60.

Note that FIG. 6B shows an example in which the main graft 10 is displaced with respect to the bifurcation artery 70 in the axial direction of the main graft 10. However, as can be understood from the above description, even when the main graft 10 is misaligned so as to rotate around its axis, the opening direction of the tubular opening 14 is the branch artery 70 as described above. It will be deformed toward the ostium of the blood vessel.

Further, as described above, the main graft 10 is typically used in a state where the branch graft 20 is connected, but as shown in FIG. 6, the main graft 10 alone can also be used. That is, depending on the position of the aortic aneurysm or the like (for example, when the aortic aneurysm or the like exists below the aorta 60 (opposite the bifurcation artery 70) in FIG. 6 (a)), the main graft 10 alone may be used. However, the blood flow to the bifurcation artery 70 can be maintained while blocking the inflow of blood to the aortic aneurysm or the like.

In FIG. 7, the connecting side end 23 of the branch graft 20 is connected to the tubular opening 14 of the main graft 10 placed in the aorta 60 as shown in FIG. 6A, and the branch is branched into the branch artery 70. An example of the case where the graft 20 is indwelled is shown. The placement of the branch graft 20 can also be performed in the same manner as described above using the stent graft placement device 1.

Specifically, after the placement of the main graft 10 is completed as shown in FIG. 6A, first, the guide wire in the stent graft placement device 1 in which the branch graft 20 is held by the holding portion 52 (not shown). ) Is passed through the bifurcation artery 70 from the inside of the main graft 10 via the tubular opening 14. Next, the entire stent graft indwelling device 1 is advanced from the inside of the main graft 10 to a predetermined position in the bifurcation artery 70 via the tubular opening 14 while being guided by the guide wire passed through the bifurcation artery 70. Then, through the same procedure as in FIGS. 5 (c) to 5 (f) described above, the entire stent graft indwelling device 1 is moved in a state where the branch graft 20 is completely exposed in the bifurcated artery 70 and self-expanded. By extracting, the placement of the branch graft 20 is completed. Contrary to the above, the branch graft 20 uses a guide wire (not shown) passed through the main graft 10 via the branch artery 70, and is a cylinder from the outside of the main graft 10 (branch artery 70 side). It may be attached to the shaped opening 14.

As shown in FIG. 7B, when the placement of the branch graft 20 is completed, the outer surface of the connecting side end portion 23 of the branch graft 20 having the above-mentioned enlarged diameter shape and the main having the above-mentioned reduced diameter shape. The main graft 10 and the branch graft 20 are connected so as to be in close contact with the inner surface of the tubular opening 14 of the graft 10. As a result, the contact area between the two can be increased and the liquidtightness between the two can be improved as compared with the case where such a reduced diameter portion and an enlarged diameter portion do not exist. As a result, blood leakage (so-called end leak) between the main graft 10 and the branch graft 20 can be suppressed.

<Action / effect>
As described above, according to the main graft 10 according to the embodiment of the present invention, a recess 13 recessed inward in the radial direction is formed on the outer peripheral surface of the main graft 10, and a cylinder extending outward in the radial direction is formed in the recess 13. A shaped opening 14 is formed. Therefore, when the main graft 10 is placed in the aorta 60, even if a misalignment occurs between the main graft 10 and the bifurcation artery 70, the tubular opening 14 opens in the recess 13 (diameter outside). The tolerance for misalignment is greater than that of conventional stent grafts (see the background technology section). Therefore, the main graft 10 can be easily placed in the aorta 60 as compared with the conventional stent graft while maintaining the function as a stent graft (for example, ensuring blood flow to the bifurcated artery 70). In other words, the main graft 10 can sufficiently exert its function as a stent graft even if the position accuracy at the time of placement is insufficient.

By connecting the main graft 10 (cylindrical opening 14) indwelled in the aorta 60 and the branch graft 20 indwelled in the bifurcation artery 70 in this way, the aorta 60 and the bifurcation artery 70 are branched. It is possible to block the inflow of blood to an aortic aneurysm or the like generated in the vicinity of the position and treat such an aortic aneurysm or the like.

Further, the tubular opening 14 does not have the skeleton portion 11, and has flexibility to the extent that the opening direction of the tubular opening 14 can be deformed by the blood flow branched from the aorta 60. Therefore, even if the position of the main graft 10 is displaced between the tubular opening 14 and the bifurcation artery 70, the tubular opening 14 is naturally guided by the blood flow toward the bifurcation artery 70. Further, the adhesion to the branch graft 20 is also improved.

Further, the entire tubular opening 14 exists inside the recessed space 15 formed by the recess 13. Therefore, even if the position of the tubular opening 14 of the main graft 10 and the bifurcation artery 70 are displaced, the opening end of the tubular opening 14 does not contact (interfere) with the inner wall surface of the aorta 60. ..

Further, the skeleton portion 11 does not exist in the vicinity of the connection portion between the tubular opening 14 and the recess 13. Therefore, the degree of freedom in the opening direction of the tubular opening 14 (flexibility of the tubular opening 14) is further increased.

Further, the tubular opening 14 has a reduced diameter shape (so-called tapered shape). Therefore, when the main graft 10 is accommodated in the stent graft indwelling device 1 for indwelling in the affected area in a contracted state in which the main graft 10 is contracted inward in the radial direction, the tubular opening 14 gradually tatami mats inward in the radial direction from the connection end. Since it is difficult for the tubular openings 14 to overlap with each other, folding becomes easy.

Further, according to the stent graft set according to the embodiment of the present invention, the outer surface of the connecting side end portion 23 of the branch graft 20 having an enlarged diameter shape and the inside of the tubular opening 14 of the main graft 10 having a reduced diameter shape. The main graft 10 and the branch graft 20 are connected so as to be in close contact with the surface. As a result, the liquidtightness between the two can be improved, and blood leakage (end leak) between the main graft 10 and the branch graft 20 can be suppressed.

<Other aspects>
The present invention is not limited to the above embodiments, and various modifications can be adopted within the scope of the present invention. For example, the present invention is not limited to the above-described embodiment, and can be appropriately modified, improved, and the like. In addition, the material, shape, size, number, arrangement location, etc. of each component in the above-described embodiment are arbitrary and are not limited as long as the present invention can be achieved.

For example, in the above embodiment, as shown in FIG. 2A, the main graft 10 has a tubular shape that extends linearly in the deployed state. However, as shown in FIG. 8A, even if the main graft 10 has a curved tube shape so that the recess 13 and the tubular opening 14 are located on the outside in the expanded state, FIG. 8B ), The recess 13 and the tubular opening 14 may have a curved tube shape so as to be located inside in the deployed state. The recessed space 15 when the main graft 10 has a curved tube shape is also shown in FIGS. 8 (a) and 8 (b).

Further, in the above embodiment, as shown in FIG. 7B, the outer surface of the connecting side end portion 23 of the branch graft 20 having an enlarged diameter shape and the tubular opening 14 of the main graft 10 having a reduced diameter shape. The main graft 10 and the branch graft 20 are connected so as to be in close contact with the inner surface of the surface. However, as shown in FIG. 9, even if such a reduced diameter portion and an enlarged diameter portion do not exist, the outer surface of the connecting side end portion 23 of the branch graft 20 and the tubular opening 14 of the main graft 10 The main graft 10 and the branch graft 20 can be connected so as to be in close contact with the inner surface.

Further, in the above embodiment, the recess 13 and the tubular opening 14 have a one-to-one correspondence with the bifurcation artery 70. However, as shown in FIG. 10, the main graft such that each of the plurality of tubular openings 14 (three in FIG. 10) extends from one recess 13 so as to correspond to each of the plurality of bifurcated arteries 70. 10 may be configured. In FIG. 10, each of the tubular openings 14 and the branch graft 20 placed in each of the bifurcation arteries 70 are connected. According to the main graft 10 of this configuration, one recess 13 can accommodate a plurality of bifurcated arteries 70. By using such a main graft 10, for example, it is possible to treat an aortic aneurysm formed at a position where a plurality of bifurcated arteries 70 are close to each other (for example, above the aorta 60 in FIG. 10). Further, although not shown, the main graft 10 may be provided with a plurality of recesses 13, and one or a plurality of tubular openings 14 may be arranged in each of the plurality of recesses 13.

Further, in the above embodiment, the entire tubular opening 14 exists inside the recessed space 15 formed by the recesses 13. However, the opening end of the tubular opening 14 may protrude to the outside of the recessed space 15. In addition, in the above embodiment, the skeleton portion 11 does not exist on the bottom surface of the recess 13 and the tubular opening 14, but the skeleton portion is on the bottom surface of the recess 13 except for the vicinity of the base end of the tubular opening 14. 11 may be present.

Further, in the above embodiment, the main graft 10 is placed in the affected part of the aorta 60 (the place where the aortic aneurysm or the like is formed), and the branch graft 20 is placed in the branch artery 70 branching from the aorta 60 near the affected part. ing. However, the main graft 10 may be placed in the affected part of an artery other than the aorta (the place where the aneurysm is formed), and the branch graft 20 may be placed in the artery branching from the artery near the affected part.

1 Stent graft indwelling device 10 Main graft (1st stent graft)
11 Skeleton part 12 Film part 13 Recession 14 Cylindrical opening 15 Recession space 20 Branch graft (second stent graft)
23 Connection side end (open end)
30 First sheath (container)
40 Second sheath (container)
50 Rod member (operation tool)
60 Aorta (main blood vessel)
70 bifurcated artery (branched blood vessel)

Claims (6)

A tubular stent graft that defines a flow path through which blood flows.
A skeleton that can contract inward in the radial direction and expand outward in the radial direction,
A film portion provided along the skeleton portion is provided.
It is possible to deform from the contracted state in which the skeleton portion is contracted to the expanded state in which the skeleton portion is expanded and the flow path is defined by the film portion.
Wherein in the expanded state, see recessed portion is radially inward of the outer peripheral surface is formed a recess having a planar bottom surface, a cylindrical shape extending radially outward from a predetermined position of the bottom surface of the recess, the blood flow is closed and the cylindrical opening capable of passing, and
The tubular opening
To have the opening facing the changeable flexibility of the cylindrical opening by the blood flow through the cylindrical opening diverted from the flow channel,
Stent graft. In the stent graft according to claim 1,
The entire tubular opening
In the expanded state, it exists inside the recessed space defined by the recesses.
Stent graft. In the stent graft according to claim 1 or 2.
The skeleton
It does not exist near the connection point between the tubular opening and the recess.
Stent graft. The first stent graft, which is the stent graft according to any one of claims 1 to 3,
A tubular second stent graft that can be connected to the tubular opening of the first stent graft.
Stent graft set. In the stent graft set according to claim 4,
The tubular opening
It has a reduced diameter shape in which the opening area becomes smaller as the distance from the connection point between the tubular opening and the recess is increased.
The second stent graft
In the vicinity of the opening end, it has an enlarged diameter shape in which the opening area increases as it approaches the opening end.
The tubular opening of the first stent graft and the vicinity of the opening end of the second stent graft are in close contact with each other.
Stent graft set. A stent graft indwelling device for indwelling a stent graft in a blood vessel.
The stent graft according to any one of claims 1 to 3.
A container in which the stent graft is housed in the contracted state and
An operating tool that releases the stent graft from the container and transforms it into the expanded state.
With,
Stent graft indwelling device.

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