JP7588933B2 - Medical Materials - Google Patents

Description

The present invention relates to a medical material for treating defects formed in biological tissue, and in particular to a medical material that is set in a catheter, delivered to the treatment site through a blood vessel, and left in the living body.

The human heart is divided into left and right chambers by tissue called the septum, with each chamber having an atrium and a ventricle, making it a two-atrium, two-ventricle arrangement: the right atrium, the right ventricle, and the left atrium and left ventricle. In a heart with this arrangement, there is a condition called atrial septal defect (ASD), in which a congenital hole called a defect is created in the atrial septum that separates the right and left atria due to a developmental disorder during fetal development.

There are two methods for treating this atrial septal defect: one is a surgical procedure that involves cutting the chest, and the other is catheter treatment that uses an occluder without cutting the chest.
In surgery (patch surgery), a heart-lung machine is used, the chest is opened, and the defect hole is closed with a patch. In catheter therapy, a closure plug is set in a catheter, the catheter is inserted into a blood vessel, and sent to the desired location (defect hole), after which the closure plug is released and left in the body. In this catheter therapy, a small, folded tool (device) called a closure plug is sent from a vein at the base of the leg (femoral vein) to the location of the hole in the atrial septum and closes the hole without opening the chest. The advantage of this catheter therapy is that it can be performed with a very small skin incision (a few millimeters) from an inconspicuous location such as the groin (groin), without the need for open-chest surgery, which requires general anesthesia.

JP2008-512139A (Patent Document 1) discloses an assembly (closure plug) used in catheter treatment of atrial septal defect. The assembly seals a passageway (defect hole) in the heart. The assembly comprises a closure device for sealing the passageway in the heart, including a first anchor used for placement proximal to a first end of the passageway, a second anchor used for placement proximal to a second end of the passageway, and a flexible extension member used for extending through the passageway and connecting to the first and second anchors, the second anchor being movable relative to the flexible extension member to change the length of the flexible extension member between the first and second anchors, and a supply system for supplying the closure device to the passageway in the heart, the supply device being set to move within the lumen of the guide catheter and including a wire for controlling the movement of the second anchor along the flexible extension member.

Patent Document 1 discloses that a patent foramen ovale (PFO) closure device (closure plug) includes a left atrial anchor, a right atrial anchor, a tether, and a lock, and that the left atrial anchor, the right atrial anchor connected to the left atrial anchor via the tether, and the lock remain in the heart to seal the PFO.

Special Publication No. 2008-512139

Patch surgery requires the use of a heart-lung machine and is highly invasive, which results in a long hospital stay. Catheter therapy does not require the use of a heart-lung machine and is less invasive, which results in a shorter hospital stay.
As disclosed in the patent, the left atrial anchor and the right atrial anchor remain in the heart. The left atrial anchor and the right atrial anchor include one or more arms that extend radially outward from a hub, preferably formed from a rolled sheet of a binary nickel-titanium alloy. The left atrial anchor and the right atrial anchor are expanded in vivo to close the defect, but once the expansion of the anchors begins, they cannot be easily restored. The anchors are collapsed using a specialized removal device, as disclosed in the patent, which has a complex structure and is difficult to operate from outside the body.

However, if the anchor gets caught in biological tissue inside the atrium and injures it, there may not be enough time to collapse the anchor with a dedicated retrieval device. In such a case, the patient must immediately switch to open-chest surgery, which is a highly invasive procedure.
Furthermore, since the metal defect plug remains in the body for the patient's lifetime, there is a concern that it may cause problems in the long term.

The present invention was developed in consideration of the above-mentioned problems with the conventional technology, and its purpose is to provide a medical material that allows for minimally invasive catheter treatment that can be released and placed at a treatment site inside the body, can be easily and reliably operated without a complex structure, and has almost no risk of long-term problems even if it remains in the body.

In order to achieve the above object, the medical material according to the present invention employs the following technical measures.
That is, the medical material according to the present invention is a medical material including a tubular body of a knitted structure using a wire having bioabsorbability and a delivery cable detachably joined to the tubular body, the tubular body has a shape in which the tubular diameter at approximately the center is smaller than the tubular diameter of other parts, a first tubular portion on a first end side which is one end in the longitudinal direction of the tubular body and a second tubular portion on a second end side which is the other end are formed around the approximately center, the first end and the second end are separated from each other around the approximately center, and the tubular diameter of the other parts is reduced, so that the medical material is inserted into a catheter. When the medical material is stored, the second end becomes the tip side of the catheter, the medical material is provided with a joint on the second end side for joining a delivery cable that has been passed from the first end side through the approximate central portion to the second end side, the delivery cable is formed so as to be able to be passed from the first end side to the outside of the medical material, and the delivery cable is configured so as to be able to press the first end toward the second end side by operating it from outside the living body.

Preferably, the delivery cable includes a cable body and an outer tube that covers the cable body from the medical material to outside the body so as to be slidable along the cable body, and can be configured so that the first end is pressed toward the second end by pushing the outer tube from outside the body.
More preferably, when the medical material to which the delivery cable is joined is stored in the catheter, the end of the outer tube on the inside of the body can be configured to abut against the first end while the end of the outer tube on the outside of the body is protruding outside the body.

More preferably, the joint is a hollow cylindrical object provided with a female thread, and is joined by screwing a male thread provided on the tip side of the delivery cable into the female thread, and when the entire medical material joined to the delivery cable by the joint is housed in the catheter, the delivery cable is operated so that the defect closure material advances toward the opening of the catheter, and the first cylindrical portion is taken out of the catheter from the tip of the catheter, followed by the second cylindrical portion, so that the first end and the second end approach each other around the approximate center, and the cylindrical diameter of the other portion is expanded to a size corresponding to the defect hole to be closed by the medical material. In vitro, the end of the delivery cable outside the living body is longer than the end of the outer tube outside the living body, and a hand-operated tool that rotates the delivery cable on its own axis to release the male thread from the female thread and detach the delivery cable from the tube.

The medical material of the present invention enables minimally invasive catheter treatment that can be released and placed at a treatment site inside the body, with easy and reliable operation without a complex structure. Furthermore, the medical material of the present invention has almost no risk of long-term problems even if it remains in the body.

FIG. 1 is an overall view of a defect closure material 100, which is an example of a medical material according to the present invention (in a state in which the distance between a first end and a second end is close to each other). FIG. 1 is an overall view of defect closure material 100 (when the distance between the first end and the second end is in an intermediate state). FIG. 2 is an overall view of defect hole closure material 100 (the entire defect hole closure material is housed within catheter 300 with the first end and second end spaced apart). FIG. 1 is an overall view of defect closure material 100 (in a state in which the second tubular portion is extended outside catheter 300 and the first tubular portion is housed within catheter 300). 3A is a partial side view of the defect closure material 100 in the state shown in FIG. 2, and FIG. 3B is a cross-sectional view taken along line AA thereof. FIG. 1 is a conceptual diagram showing the case where a defect closure material 100 is used in catheter treatment for an atrial septal defect. FIG. 7 is an enlarged view (part 1) of part B in FIG. 6 showing the procedure of catheter treatment. FIG. 7 is an enlarged view (part 2) of part B in FIG. 6 showing the procedure of catheter treatment. FIG. 7 is an enlarged view (part 3) of part B in FIG. 6 showing the procedure of catheter treatment. 13 is an enlarged view of a joint 422 provided at the distal end of the defect closure material 100 and a delivery cable 500 joined to the joint 422 by screwing. FIG. This is a plan view (top view) of a catheter 300 including the distal end (second end 122) and proximal end (first end 112) of the defect closure material 100, as well as a delivery cable 500 and a proximal operating jig 560. FIG. 12 is a perspective view of FIG.

The medical material according to the present invention will be described in detail below with reference to the drawings. In the following, a defect closure material used in catheter treatment will be described as an example of the medical material according to the present invention, but it is also suitable for closing other openings or passages, such as other openings in the heart, such as ventricular septal defect and patent ductus arteriosus, and openings or passages in other parts of the body (for example, the stomach), such as arteriovenous fistulas. Therefore, the defect closure material according to the embodiment of the present invention is not limited to use for closing holes in atrial septal defects. In addition, the medical material according to the present invention may include a cylinder of a knitted tissue (a cylinder in which a first cylinder part 110 on the proximal side arranged on the right atrium side and a second cylinder part 120 on the distal side arranged on the left atrium side are connected via a substantially central part 130) itself, as described later, and a delivery cable 500 detachably joined to this cylinder.

Furthermore, in the following embodiment, the mesh-like structure of the defect hole closure material (closure plug) 100 (hereinafter sometimes referred to as medical material 100), which is an example of the medical material according to the present invention, is described as being formed by weaving bioabsorbable fibers (an example of wire material), but the present invention is not limited to this. Any defect hole closure material that can perform catheter treatment to close a defect hole formed in a living body may be used, and the mesh-like structure and material are not limited as long as they have the first and second characteristics described below and exhibit the first to third actions, and for example, the material may be knitted with wire material other than bioabsorbable fibers. It is preferable that such wire material has a certain degree of hardness in order to provide the shape retention of the defect hole closure material (different from the shape retention provided by the shape retention member described below).

[Basic configuration]
FIG. 1 shows an overall view of defect hole closure material 100 in accordance with the present embodiment (with first end 112 and second end 122 close to each other), FIG. 2 shows another overall view of defect hole closure material 100 (with first end 112 and second end 122 in an intermediate state), FIG. 3 shows yet another overall view of defect hole closure material 100 (with the entire defect hole closure material 100 contained within catheter 300 and first end 112 and second end 122 separated from each other), and FIG. 4 shows yet another overall view of defect hole closure material 100 (with second tubular portion 120 extended outside catheter 300 and first tubular portion 110 contained within catheter 300). With regard to the storage relationship of this defect hole closure material 100 within the catheter 300, Figure 3 shows a state in which the entire defect hole closure material 100 is stored within the catheter 300, and Figure 4 shows a state in which half of this defect hole closure material 100 (the side of the first tubular portion 110) is stored within the catheter 300.

In terms of time transition, the defect hole closure material 100, which is entirely contained inside the catheter 300 shown in Figure 3 (the space formed by the inner wall 310), changes to the state shown in Figure 4 when the second tubular portion 120 is extended from the opening 320 of the catheter 300 in the direction of arrow Y, and changes to the state shown in Figure 1 when the first tubular portion 110 is further extended in the direction of arrow Y. Here, the state of the defect hole closure material 100 shown in Figure 2 is a virtual state in which the distance between the first end 112 and the second end 122 is in an intermediate state. Note that "hand" and "base" are synonymous.

As shown in these figures, the defect hole closure material 100 is generally formed as a tube with a woven structure using wire rod, and has a shape in which the diameter of the tube at approximately the center 130 is smaller than the diameter of the tube in other parts, and a first tube portion 110 on the first end portion 112 side in the longitudinal direction of the tube in the defect hole closure material 100 and a second tube portion 120 on the other end portion (second end portion 122) side are formed with the approximately center portion 130 as the center.

And what is characteristic is that when the first end 112 and the second end 122 are separated from each other about the approximately central portion 130 and the diameter of the remaining portions is reduced and the defect hole closure material 100 is stored in the catheter 300 (as shown in FIG. 3), the second end 122 side becomes the tip side of the catheter 300. In this case, the defect hole closure material 100 has a joint 422 on the second end 122 side for joining the operation wire 500 (hereinafter sometimes referred to as the delivery cable 500) that is passed from the first end 112 side to the second end 122 side via the approximately central portion 130. Furthermore, the defect hole closure material 100 is formed so that the delivery cable 500 can be passed from the first end 112 side to the outside of the defect hole closure material 100 (for example, a hole through which the cable body 510 of the delivery cable 500 passes is formed in the first end 112).

As shown in Figs. 10 to 12, the joint 422 is a hollow cylindrical object (e.g., made of metal) provided with a female thread 424, and is joined by threading a male thread 514 provided on the tip side of the cable body 510 of the delivery cable 500 into the female thread 424. Note that by rotating (rotating) the cable body 510 in the living body in the direction opposite to the direction in which the male thread 514 threads into the female thread 424, this threaded joint can be released and the defect closure material 100 and the delivery cable 500 can be separated.

Here, as shown in Figures 10 to 12, the hollow cylindrical object forming this joint 422 is open on the first tubular portion 110 side and has a female thread 424 so that it can be screwed into a male thread 514 provided on the tip side of the cable main body 510 of the delivery cable 500, and the side opposite the first tubular portion 110 side is closed.
This is preferable in that closing the side opposite the first tubular portion 110 makes it easier to operate the delivery cable when pushing the defect closure material through the sheath and prevents the defect closure material from twisting.

As will be described in detail later in the section on [Use Mode], when the entire defect hole closure material 100, joined to the delivery cable 500 by the joint 422, is housed in the catheter 300, the delivery cable 500 is operated (so that the defect hole closure material 100 advances toward the opening 320 of the catheter 300) and the first tube portion 110 is brought out of the catheter 300, followed by the second tube portion 120, from the tip of the catheter 300, so that the first end portion 112 and the second end portion 122 approach each other approximately at the center portion 130, and the tube diameter of the other portions is expanded to a size corresponding to the defect hole to be closed by the defect hole closure material 100.

At this time, a joint 422 is provided on the second end 122 side, and the tip of the delivery cable 500 is joined to this joint 422, so that both the second tubular portion 120 and the first tubular portion 110 are not pushed out to the outside of the catheter 300 (as in the case where the joint 422 joined to the tip of the delivery cable 500 is provided on the first end 122 side), but are pulled out to the outside of the catheter 300. When pushed out, defect hole closure material 100 may twist, preventing first end 112 and second end 122 from properly approaching each other about approximately central portion 130, and causing the tube diameter of other portions to not properly expand to a size corresponding to the defect to be closed by defect hole closure material 100; however, when pulled, such twisting of defect hole closure material 100 is prevented, and first end 112 and second end 122 can properly approach each other about approximately central portion 130, allowing the tube diameter of other portions to properly expand to a size corresponding to the defect to be closed by defect hole closure material 100.

Furthermore, FIG. 5(A) shows a partial side view of the defect hole closure material 100, and FIG. 5(B) shows a cross-sectional view taken along the line A-A of FIG. 2 and FIG. 5(A). Note that FIG. 5(B) is a cross-sectional view of the defect hole closure material 100 (more specifically, the second tubular portion 120), but shows a cross-section of the cable body 510 of the delivery cable 500, and does not show the stitches of the bioabsorbable fiber 150 that can be seen from the direction of the arrow A. In addition, in FIG. 1 to FIG. 5, in order to facilitate understanding of the presence of the cable body 510 of the delivery cable 500 located inside the defect hole closure material 100 and the stitches of the bioabsorbable fiber 150, the bioabsorbable fiber 150 arranged on the far side of the page is not shown, and in order to facilitate understanding of the external shape of the defect hole closure material 100, there are some parts in which the external shape of the defect hole closure material 100 is shown by dotted lines.

As shown in these figures (particularly FIG. 2), the defect closure material 100 is formed of two cylinders (first cylinder 110 and second cylinder 120) of a mesh-like tissue using a bioabsorbable material, and has a shape composed of two such cylinders, such as an hourglass shape, a figure of eight shape, a double spindle shape (a shape of two long, thin rod-like spindle-shaped objects with a thick center and thin ends) or a peanut shape (the external shape of a peanut shell containing two nuts). The defect closure material 100 having such a shape has a shape in which the approximate center 130 of the cylinder is narrowed so that the diameter of the cylinder at the approximate center 130 is smaller than the diameter of the other parts. In other words, the first cylinder 110 on the first end 112 side and the second cylinder 120 on the second end 122 side are formed with the approximate center 130 as the center.

Although not limited thereto, the first tubular portion 110 and the second tubular portion 120 of this defect hole closure material 100 are integrally woven so that the tubular diameter of approximately the central portion 130 is smaller than the tubular diameter of the other portions, and the overall shape of this defect hole closure material 100 is formed into an hourglass shape, a figure-eight shape, a double spindle shape, or a peanut shape composed of two cylinders.
In this case, such an hourglass-shaped, figure-of-eight-shaped, double spindle-shaped, or peanut-shaped form (three-dimensional paper template) is used, and one bioabsorbable fiber 150 is knitted to fit the form, thereby forming the overall shape of the defect hole closure material 100. Furthermore, although not limited thereto, the defect hole closure material 100 may be formed into an hourglass-shaped, figure-of-eight-shaped, double spindle-shaped, or peanut-shaped form composed of two cylinders by, for example, knitting a cylinder of approximately the same diameter by integrally knitting the first tubular portion 110 and the second tubular portion 120 and then heat setting the resulting cylinder.

As will be described in detail later, by realizing such a shape by knitting, defect hole closure material 100, which is entirely contained inside catheter 300 shown in FIG. 3 (the space formed by inner wall 310), is operated so that delivery cable 500, the tip of which is joined to joint 422 on the second end 122 side, is operated (so that defect hole closure material 100 advances in the direction of opening 320 of catheter 300), and second tubular portion 120 is pulled out from opening 320 at the tip of catheter 300 in the direction of arrow Y to the outside of catheter 300, whereby second tubular portion 120 enters the space formed by inner wall 310 of catheter 300. 4, and then the delivery cable 500 is operated (so that the defect closure material 100 advances (further) toward the opening 320 of the catheter 300) and the first tubular portion 110 is extended in the direction of arrow Y from the opening 320 at the tip of the catheter 300 so as to be pulled out to the outside of the catheter 300. As a result, following the second tubular portion 120, the first tubular portion 110 is also released from the space formed by the inner wall 310 of the catheter 300, and the first tubular portion 110 (and the second tubular portion 120) attains the state shown in FIG. 1, thereby achieving a change in shape (a time-transient change in shape).

As shown in FIG. 1, when the defect closure material 100 is not contained in the catheter 300 and exists isolated in space, the first end 112 and the second end 122 approach each other around the approximate center 130, and the diameters of the first tubular portion 110 and the second tubular portion 120, which are the portions other than the approximate center 130, are expanded. It is particularly preferable that the expanded diameters of the first tubular portion 110 and the second tubular portion 120 (the portions other than the approximate center 130) are expanded to a size corresponding to the defect that is closed by the defect closure material 100.

As shown in FIG. 3, when the defect closure material 100 is stored in a catheter 300, for example, and thus does not exist isolated in space but has limited radial freedom, the first end 112 and the second end 122 are separated from each other around the approximate center 130, and the diameters of the first tubular portion 110 and the second tubular portion 120, which are the other portions, are reduced. It is particularly preferable that the diameters of the first tubular portion 110 and the second tubular portion 120 (the other portions other than the approximate center 130) are reduced to a size corresponding to the catheter 300 in which the defect closure material 100 is stored.

The diameter of cable main body 510 of delivery cable 500 is smaller than the tube diameter of approximately central portion 130 .
In this way, the defect hole closure material 100 can be, for example, stored in the catheter 300 to restrict its radial freedom, or pulled out from the catheter 300 to the outside of the catheter 300 so as not to restrict its radial freedom, thereby allowing the first end 112 of the cylindrical body of the defect hole closure material 100 to be separated (stored in the catheter 300) or brought closer together (pulled out from the catheter 300). When this defect closure material 100 is removed from the catheter 300, for example, and the radial freedom is not restricted, as shown in FIG. 1, the first end 112 and the second end 122 come closer to each other, and the tube diameter of the other parts of the approximately central portion 130 (the tube diameter of the trunk portions of the first tubular portion 110 and the second tubular portion 120) is expanded. When the defect closure material 100 is retracted into the catheter 300 and the radial freedom is restricted, as shown in FIG. 3, the first end 112 and the second end 122 move away from each other, and the tube diameter of the other parts of the approximately central portion 130 (the tube diameter of the trunk portions of the first tubular portion 110 and the second tubular portion 120) is reduced.

Furthermore, as shown in FIG. 4, when the second tube portion 120 is pulled out from the catheter 300 in the direction of the arrow Y, the shape of the second tube portion 120, which was restricted by the inner wall 310 of the catheter 300 (the radial freedom was limited), can freely change, and only the tube diameter of the trunk portion of the second tube portion 120 is expanded. Furthermore, when the first tube portion 110 is pulled out from the catheter 300 in the direction of the arrow Y, the shape of the first tube portion 110, which was restricted by the inner wall 310 of the catheter 300 (the radial freedom was limited), can also freely change, and the tube diameter of the trunk portion of the first tube portion 110 is also expanded.

In this defect closure material 100, the first tubular portion 110 and the second tubular portion 120 are made of a woven fabric (coarsely woven), knitted fabric, braided woven fabric, or tubular knitted fabric of bioabsorbable fibers 150, and the entire structure is made into a knitted structure. It should be noted here that the knitted structure is not limited to knitted fabrics formed by knitting, but includes mesh-like structures formed by coarse weaving such as a screen door, as described above. In other words, it does not matter whether the structure is called a knitted structure or a mesh-like structure.

In this way, basically, the first tubular portion 110 and the second tubular portion 120 are all made of a bioabsorbable material, except for the joint portion 422 which is made of a metal piece such as a metal (e.g., stainless steel), and therefore the entire defect hole closure material 100 except for the joint portion 422 is bioabsorbable (the material of the delivery cable 500 is not particularly important, since it does not constitute the medical material according to the present invention and does not remain in the living body). Furthermore, the defect hole closure material 100 is treated by changing its shape to close the defect hole, and the defect hole closure material 100, including the joint portion 422, is formed with a material, knit shape, fiber structure, and fiber cross section that do not damage the tissue in the living body even if the shape of the defect hole closure material 100 changes in this way in the living body.

Although the joint 422 is usually made of, for example, stainless steel and is not bioabsorbable, it may be made bioabsorbable by using a magnesium-based alloy, as described below. Using a bioabsorbable alloy for the joint 422 is advantageous in that it reacts to X-ray imaging, and using a bioabsorbable alloy is advantageous in that the metal component does not remain in the body for the rest of the body, eliminating the problem of concern about long-term malfunctions.

The bioabsorbable fibers 150 constituting the first tube portion 110 and the second tube portion 120 are at least one selected from, for example, polyglycolic acid, polylactide (D,L,DL form), polycaprolactone, glycolic acid-lactide (D,L,DL form) copolymer, glycolic acid-ε-caprolactone copolymer, lactide (D,L,DL form)-ε-caprolactone copolymer, poly(p-dioxanone), glycolic acid-lactide (D,L,DL form)-ε-caprolactone copolymer, etc., and are used in the form of monofilament thread, multifilament thread, twisted thread, braided cord, etc., but are preferably used in the form of monofilament thread.

Furthermore, the material of the bioabsorbable fiber 150 may be a bioabsorbable alloy, such as an alloy that uses magnesium as a raw material.
The diameter of the bioabsorbable fiber 150 is about 0.001 mm to 1.5 mm, and a fiber diameter and type appropriate for the catheter treatment to be applied are selected. The cross section of the bioabsorbable fiber 150 may be any of a circle, an ellipse, or other irregular shape (for example, a star shape), provided that it does not damage tissue in the body. Furthermore, the surface of the bioabsorbable fiber 150 may be hydrophilized by plasma discharge, electron beam treatment, corona discharge, ultraviolet irradiation, ozone treatment, or the like. The bioabsorbable fiber 150 may be coated or impregnated with an X-ray opaque material (for example, barium sulfate, gold chips, platinum chips, etc.), treated with a drug (for example, a drug suitable for catheter treatment of atrial septal defect), or coated with a natural polymer such as collagen or gelatin, or a synthetic polymer such as polyvinyl alcohol or polyethylene glycol.

The first tubular portion 110 and the second tubular portion 120 are produced by, for example, using a braiding machine having multiple (e.g., 8 or 12) yarn feeders around a silicone rubber tube (not shown) of a desired outer diameter as a monofilament thread to produce a braided fabric, or knitting into a knitted structure of a tube of approximately the same diameter using a circular knitting machine (not shown). After knitting, as described above, the first tubular portion 110 and the second tubular portion 120 are formed into an hourglass shape, a figure of eight shape, a double spindle shape, or a peanut shape consisting of two tubes. The tube diameters of the first tubular portion 110 and the second tubular portion 120 are smaller than the inner diameter of the catheter 300 when contracted, and are suitable for catheter treatment of atrial septal defect when expanded. For example, the diameter of the first tubular portion 110 and the second tubular portion 120 when expanded is about 5 mm to 80 mm, preferably about 15 mm to 25 mm. The length of the first tubular portion 110 and the second tubular portion 120 and the density of the mesh-like tissue of the defect closure material 100 also provide a density suitable for catheter treatment of atrial septal defect. The diameter and length of the first tubular portion 110 and the second tubular portion 120 do not need to be the same, and may be changed to be suitable for catheter treatment of atrial septal defect.

As described above, defect closure material 100 according to the present embodiment has the following features.
(First feature) The first cylindrical portion 110 and the second cylindrical portion 120 are tapered at the approximate center portion 130, and are formed into an hourglass shape, a figure-8 shape, a double spindle shape, or a peanut shape.
(Second feature) A joint 422 is provided on the second end 122 side (the tip side of the catheter 300) for joining an operating wire 500 that is passed from the first end 112 side through approximately the central portion 130 to the second end 122 side, and this delivery cable 500 is formed so that it can be passed from the first end 112 side to the outside of the defect closure material 100.

Then, due to the first and second features, when the second tubular portion 120 is pulled out from the catheter 300 to the outside of the catheter 300, the shape of the second tubular portion 120, which has been restricted by the inner wall 310 of the catheter 300, can freely change, and only the tubular diameter of the trunk portion of the second tubular portion 120 is expanded, and further, when the first tubular portion 110 is pulled out from the catheter 300 to the outside of the catheter 300, the shape of the first tubular portion 110, which has been restricted by the inner wall 310 of the catheter 300, can also freely change, and the tubular diameter of the trunk portion of the first tubular portion 110 is also expanded. Then, the tubular diameter of the trunk portion is expanded to a size corresponding to the defect hole to be closed by the defect hole closure material 100. In particular, the defect hole closure material 100 is suitable for catheter treatment of atrial septal defect in that it exhibits the following actions.

(First action) By separating the first end 112 and the second end 122 approximately around the central portion 130 (by pulling the first end 112 and the second end 122 in opposite directions so as to separate them), and reducing the tubular diameters of the other portions, the first tubular portion 110 and the second tubular portion 120, the tubular diameter of the defect hole closure material 100 can be made smaller than the inner diameter of the catheter 300, and the material can be set into the catheter 300.
(Second action) A joint 422 is provided on the side of second end 122, and the tip of delivery cable 500 is joined to this joint 422, so that both second tubular portion 120 and first tubular portion 110 are not pushed out to the outside of catheter 300 but are pulled out to the outside of catheter 300. This prevents defect hole closure material 100 from twisting when pushed out, which prevents first end 112 and second end 122 from properly approaching each other about central portion 130, and prevents the tube diameter of other portions from properly expanding to a size corresponding to the defect hole to be closed by defect hole closure material 100. By pulling, such twisting of defect hole closure material 100 is prevented, and first end 112 and second end 122 can properly approach each other about central portion 130, allowing the tube diameter of other portions to properly expand to a size corresponding to the defect hole to be closed by defect hole closure material 100. This allows the first tubular portion 110 arranged on the right atrium side and the second tubular portion 120 arranged on the left atrium side to approach each other approximately around the central portion 130, thereby closing the hole in the atrial septum.

(Third effect) All of the materials constituting this defect closure material 100 (except for the joint 422 in some cases) are bioabsorbable materials, and therefore are ultimately absorbed into the body, almost eliminating the possibility of malfunctions in the long term.
Further, preferred embodiments of the present invention will be described below.
As described above, this defect closure material 100 is preferably configured to include a cylinder of a knitted tissue using a bioabsorbable wire (a cylinder in which a proximal first cylinder section 110 arranged on the right atrium side and a distal second cylinder section 120 arranged on the left atrium side are connected via a substantially central section 130) and a delivery cable 500 (more specifically, a cable main body 510 and an outer cylinder 550) detachably joined to this cylinder. The delivery cable 500 is configured to be capable of pressing the proximal first end section 112 toward the distal second end section 122 by operating it from outside the living body.

More specifically, the delivery cable 500 is preferably configured to include a cable main body 510 and an outer tube 550 that covers the cable main body 510 from the tube itself of the defect closure material 100 to outside the body so that it can slide along the cable main body 510. By pushing the outer tube 550 from outside the body, the first end 112 on the proximal side can be pressed toward the second end 122 on the distal side.

Regarding the length of the outer tube 550, when the tube of the defect closure material 100 to which the delivery cable 500 is joined is housed in the catheter 300 (in the state shown in FIG. 3), as shown in FIG. 6, the end 552 inside the body of the outer tube 550 abuts against the first end 112 with the end outside the body of the outer tube 550 protruding from the body. This will be described in detail with reference to FIGS. 1 to 4 and 6. The distance (hereinafter sometimes simply referred to as distance) from the end face of the tip-side joint 422 (the joint 412 side on the proximal side) of the cable main body 510 of the delivery cable 500 inside the body to the end face inside the body of the outer tube 550 is L(2) in the state shown in FIG. 1, which shows the shortest case, and is L(1) (>L(2)) in the state shown in FIG. 3, which shows the longest case. In the states shown in FIGS. 2 and 4, the distance is L(1) to L(2). In either case, the end 552 of the outer tube 550 inside the living body can abut against the first end 112, and in either case, the end of the outer tube 550 outside the living body protrudes outside the living body as shown in Figure 6. And because of this distance and positional relationship, as well as the shape change of the tube itself, in either state, the end 552 of the outer tube 550 inside the living body abuts against the first end 112, so that the first end 112 on the proximal side can be pressed toward the second end 122 on the tip side by pushing the outer tube 550 from outside the living body.

Here, as shown in Fig. 10(A), the end 552 of the outer tube 550 inside the living body abuts against the first end 112, and the first end 112 on the proximal side can be pressed toward the second end 122 on the tip side by pushing the outer tube 550 from outside the living body. Alternatively, as shown in Fig. 10(B), a flange 556 may be provided at the end of the outer tube 550 inside the living body, an end face 554 of the flange 556 abuts against the first end 112, and the first end 112 on the proximal side can be pressed toward the second end 122 on the tip side by pushing the outer tube 550 from outside the living body. With this configuration, the end surface 554 of the flange 556 inside the living body abuts against the first end 112, and by pushing the outer tube 550 from outside the living body, the end surface 554 of the flange 556 can preferably press the first end 112 on the proximal side toward the second end 122 on the tip side (preferably pressing the first end 112 with the end surface, not the end). Note that the maximum outer diameter of the flange 556 is smaller than the inner diameter d of the catheter 300.

Here, the remarkable effect of this configuration will be explained. Biodegradable materials, which are particularly preferably used as the material for the tubular body of the medical material 100 itself, may have slow or poor expandability when compared with shape memory alloys such as nickel-titanium alloys. In such a case, as shown in FIG. 4, when the first tubular part 110 on the base side is expanded after the second tubular part 120 on the tip side is expanded, the delivery cable 500 is operated (from the state shown in FIG. 4) (so that the defect closure material 100 advances (further) toward the opening 320 of the catheter 300) and the first tubular part 110 is pulled out from the opening 320 at the tip of the catheter 300 in the direction of the arrow Y as if pulled out to the outside of the catheter 300, and the first tubular part 110 is pulled out from the opening 320 at the tip of the catheter 300 in the direction of the arrow Y ... second tubular part 120 is followed by the first tubular part 110. When the first tubular portion 110 is released from the space formed by the inner wall 310 of the catheter 300 and the first tubular portion 110 (and the second tubular portion 120) change to the state shown in FIG. 1 (time-transient change in shape), the first end 112 on the proximal side is pressed toward the second end 122 on the distal side by pushing the outer tube 550 from outside the living body, so that the first tubular portion 110 can be preferably deployed even if a biodegradable material is used for the first tubular portion 110.

Here, in the present invention, pressing the first end 112 on the proximal side toward the second end 122 on the tip side by operating from outside the living body is not limited to the case (timing) shown in Figure 4 described above.
Incidentally, although not limited to, outer tube 550, for example, when the outer diameter of the cable body of delivery cable 500 is 1.5 mm, it is preferable to cover it with a fluorine tube having an inner diameter of 1.93 mm (outer diameter 2.53 mm) that has an inner diameter larger than the outer diameter of 1.5 mm.

1 and 9, in which the diameter of the other parts of the tube is expanded to a size corresponding to the defect hole that is closed by the tube body itself (for example, defect hole 252 in atrial septum 250 separating right atrium 210 and left atrium 230), in an ex vivo environment, as shown in FIG. 6, the end of cable main body 510 of delivery cable 500 on the ex vivo side is longer than the end of outer tube 550 on the ex vivo side (cable main body 510 is exposed from outer tube 550), and the male thread 514 that rotates cable main body 510 and the female thread 424 are released from the tube to the end of the exposed cable main body 510 on the ex vivo side.
It is also preferable that a hand-operated jig 560 for releasing the male thread 514 from the female thread 424 is connected to the hand-operated jig 560. Here, when the direction in which the male thread 514 screws into the female thread 424 is a right-handed thread (the female thread 424 screws by rotating in a clockwise direction), the hand-operated jig 560 is used to rotate the cable main body 510 in the opposite direction, that is, counterclockwise, thereby releasing the connection formed by the screwing and separating the cylindrical body itself from the delivery cable 500.

6, 11 and 12, this hand operation jig 560 includes a jig body 562 having an octagonal cross section with a through hole corresponding to the outer diameter of the cable body 510, and a set screw 564 for preventing the cable body 510 inserted into the through hole from rotating freely within the jig body 562, and is configured to allow the cable body 510 to be suitably rotated (rotated) by rotating (turning) the jig body 562. Note that the through hole does not have to penetrate all the way through as long as it is provided at least up to the position of the set screw 564.
The use of this defect closure material 100 in catheter treatment for an atrial septal defect will be described with reference to FIGS.

[Usage]
Fig. 6 shows a conceptual diagram of the case where this defect hole closure material 100 is used in catheter treatment for atrial septal defect, and Figs. 7 to 9 show enlarged views of part B in Fig. 6, which show the procedure of this catheter treatment. Note that in the following, only matters specific to the mode of use of defect hole closure material 100 according to the present embodiment will be described, and as general matters are the same as those in known catheter treatment for atrial septal defect, detailed description thereof will not be repeated here.

As shown in FIG. 6, the human heart 200 is composed of two atria and two ventricles: the right atrium 210, which is connected to the superior vena cava and inferior vena cava and receives venous blood from the entire body; the right ventricle 220, which is connected to the right atrium 210 via the pulmonary artery and tricuspid valve 260 and sends venous blood to the lungs; the left atrium 230, which is connected to the pulmonary vein and receives arterial blood from the lungs; and the left ventricle 240, which is connected to the left atrium 230 via the aorta and mitral valve 270 and sends arterial blood to the entire body. Atrial septal defect is a disease in which a defect hole 252 is opened in the atrial septum 250 that separates the right atrium 210 and the left atrium 230. In FIG. 6, for ease of understanding, the tip side of the catheter 300 (the tip side from the break line in part B) is shown by a virtual line, and the defect hole closure material 100 stored in the catheter 300 is shown by a solid line.

First, outside the body, the first end 112 and the second end 122 of the defect hole closure material 100, which expands to an appropriate size for the defect hole 252, are pulled in a direction away from each other so that the diameter of the defect hole closure material 100 becomes smaller than the inner diameter of the catheter 300, and the material is set in the catheter 300. The catheter 300 containing the defect hole closure material 100 is inserted from the femoral vein (see FIG. 3), and the catheter 300 (containing the defect hole closure material 100) is moved (together with the contained defect hole closure material 100) in the direction of arrow X(1) to bring the catheter 300 containing the defect hole closure material 100 closer to the left atrium 230 side through the defect hole 252 from the right atrium 210 side.

6 and 7, the catheter 300 containing the defect hole closure material 100 is stopped at a position where the approximate center 130 of the defect hole closure material 100 corresponds to the vicinity of the defect hole 252. The delivery cable 500 is operated (so that the defect hole closure material 100 advances toward the opening 320 of the catheter 300), and since the tip of the delivery cable 500 is joined to the joint 422 on the tip side in the living body, the second tube portion 120 is not pushed out of the catheter 300 as if it were pushed out of the catheter 300, but is pulled out of the catheter 300 in the direction of the arrow Y, which is the direction toward the outside of the catheter 300. Then, the second tube portion 120, whose shape (in the radial direction) was restricted by the inner wall 310 of the catheter 300, can freely change its shape, and only the tube diameter of the trunk portion of the second tube portion 120 is expanded as shown in FIG. 8.

Then, the delivery cable 500 is further manipulated (so that the defect closure material 100 advances (further) toward the opening 320 of the catheter 300), and since the tip of the delivery cable 500 is joined to the joint 422 on the tip side in the living body, the first tube portion 110 is not pushed out of the catheter 300 as if it were being pushed out, but is pulled out of the catheter 300 in the direction of the arrow Y, which is the direction toward the outside of the catheter 300, following the second tube portion 120. Then, the first tube portion 110, whose shape (in the radial direction) was restricted by the inner wall 310 of the catheter 300, can also freely change shape, and only the tube diameter of the trunk portion of the first tube portion 110 is expanded as shown in FIG. 9.

That is, when the delivery cable 500 is operated (so that the defect closure material 100 advances toward the opening 320 of the catheter 300) with the approximate center 130 of the defect closure material 100 positioned in the vicinity of the defect 252, the second tube portion 120 arranged on the left atrium side expands first, and then the first tube portion 110 arranged on the right atrium side expands later. As a result, the first tube portion 110 arranged on the right atrium 210 side and the second tube portion 120 arranged on the left atrium 230 side approach each other with the approximate center portion 130 (defect 252) as the center, and the first tube portion 110 and the second tube portion 120 expand. Finally, as shown in FIG. 9, the atrial septum 250 is sandwiched between the first tube portion 110 and the second tube portion 120, and the defect closure material 100 closes the defect 252 in the atrial septum 250.

Here, the delivery cable 500 is operated (so that the defect closure material 100 advances toward the opening 320 of the catheter 300) with the approximate center 130 of the defect closure material 100 positioned to correspond to the vicinity of the defect 252, and in the case where the second tube portion 120 arranged on the left atrium side expands first and then the first tube portion 110 arranged on the right atrium side expands later (i.e., when the first tube portion 110 on the base side is expanded after the second tube portion 120 on the tip side is expanded), the outer tube 550 covering the cable body 510 of the delivery cable 500 is pushed from outside the living body. By this operation, the first end portion 112 on the hand side is pressed toward the second end portion 122 on the tip side, so that even if a biodegradable material is used for the first tube portion 110, the first tube portion 110 can be preferably expanded following the second tube portion 120 that is expanded first.

Then, inside the body, the cable body 510 is rotated (spinned) so that the male thread 514 rotates (rotates) in the opposite direction to the direction in which the male thread 514 screws into the female thread 424, and the connection between the defect hole closure material 100 and the delivery cable 500 caused by this screwing is released. At this time, the defect hole closure material 100 provided to close the defect hole 252 does not rotate (spin).

At this time, as shown in FIG. 6, outside the living body, the end of the cable body 510 of the delivery cable 500 on the outside of the living body is longer than the end of the outer tube 550 on the outside of the living body (the cable body 510 is exposed from the outer tube 550), and the hand-operated jig 560 is connected to the exposed end of the cable body 510 on the outside of the living body. If the direction in which the male thread 514 screws into the female thread 424 is a right-handed thread (rotating clockwise to screw), the hand-operated jig 560 is rotated counterclockwise, which is the opposite direction, to rotate the cable body 510 (rotating on its own axis), thereby suitably releasing the connection formed by this screwing, and suitably separating the tube itself from the delivery cable 500.

Then, the catheter 300 (with the delivery cable 500 stored inside) is moved in the direction of the arrow X (2), and the catheter 300 (and the delivery cable 500) is removed from the body, completing the treatment. This leaves the defect closure material 100 (except for the joint 422, in some cases) made entirely of bioabsorbable material in the body (more precisely, in the vicinity of the defect 252). As the material of the defect closure material 100 placed in the body in this way is entirely bioabsorbable (except for the joint 422, in some cases), it is eventually absorbed by the body, and there is almost no possibility of malfunction in the long term.

In this manner of use, when first tubular portion 110 is pushed out from catheter 300 in the direction of arrow Y following second tubular portion 120 with operating wire 500, defect hole closure material 100 may twist, and first end 112 and second end 122 may not be able to approach each other appropriately around approximately central portion 130, so that the tubular diameter of other portions may not properly expand to a size corresponding to the defect to be closed by defect hole closure material 100; however, when pulled, such twisting of defect hole closure material 100 is suppressed, and first end 112 and second end 122 may be able to approach each other appropriately around approximately central portion 130, so that the tubular diameter of other portions may properly expand to a size corresponding to the defect to be closed by defect hole closure material 100.

In particular, even if a biodegradable material that is inferior in expandability to a shape memory alloy is used as the material for the tube itself of the medical material 100, when the first tube part 110 on the base side is expanded after the second tube part 120 on the tip side is expanded, the first end part 112 on the proximal side is pressed toward the second end part 122 on the tip side by pushing the outer tube 550 from outside the living body, so that the first tube part 110 can be suitably expanded. Furthermore, by rotating the hand-operated operating tool 560 in the direction opposite to the direction in which the male thread 514 is screwed into the female thread 424 to rotate (rotate) the cable main body 510, the joint formed by this screwing can be suitably released, and the tube itself and the delivery cable 500 can be suitably separated.

As described above, the defect hole closure material 100 of this embodiment (here, this defect hole closure material includes a cable main body 510, an outer tube 550 covering the cable main body 510, and a hand-operated jig 560 provided on the cable main body 510 exposed from the outer tube 550) is made entirely of bioabsorbable material (except in some cases for the joint 422) and is ultimately absorbed into the body, so there is almost no possibility of malfunction in the long term. Furthermore, when defect hole closure material 100 is pushed out from catheter 300, defect hole closure material 100 may twist and first end 112 and second end 122 may not be able to approach each other appropriately around approximately central portion 130, and the tube diameter of the other portions (first tubular portion 110 and second tubular portion 120) may not be appropriately expanded to a size corresponding to the defect hole to be closed by defect hole closure material 100; however, when joint 422 is provided on the second end 122 side and the tip of delivery cable 500 is joined to joint 422 and pulled when defect hole closure material 100 is pushed out from catheter 300, such twisting of defect hole closure material 100 is suppressed and first end 112 and second end 122 may be able to approach each other appropriately around approximately central portion 130, and the tube diameter of the other portions (first tubular portion 110 and second tubular portion 120) may be appropriately expanded to a size corresponding to the defect hole to be closed by defect hole closure material 100. Furthermore, when the first tubular portion 110 on the base side is deployed after the second tubular portion 120 on the tip side is deployed, the first end portion 112 on the proximal side is pressed toward the second end portion 122 on the tip side by pushing the outer tube 550 from outside the living body, so that the first tubular portion 110 can be suitably deployed. Furthermore, by rotating the hand-held operating jig 560 in the direction opposite to the direction in which the male thread 514 is screwed into the female thread 424 to rotate (rotate) the cable main body 510, the joint formed by this screwing can be suitably released, and the tubular body itself and the delivery cable 500 can be suitably separated. As a result, simply by manipulating the delivery cable 500 so that the defect closure material 100 advances toward the opening 320 of the catheter 300 at the location of the defect, the diameter of the defect closure material 100 can be easily changed so that the two cylinders (the first cylinder portion 110 and the second cylinder portion 120) approach each other, and the shape can be easily fixed, thereby closing the defect in the atrial septum.

It should be noted that the embodiments disclosed herein are illustrative in all respects and are not restrictive. The scope of the present invention is indicated by the claims rather than the above description, and is intended to include all modifications within the meaning and scope of the claims.

The present invention is suitable for medical materials that are set in catheters to treat defects formed in biological tissues, and is particularly preferable in that it can be released and placed at the treatment site, allowing for minimally invasive treatment, there is almost no risk of long-term problems even if the medical material remains in the body, and it is easy to use.

100 Medical materials (closure plugs)
110 First tubular portion 112 First end portion 120 Second tubular portion 122 Second end portion 130 Approximately central portion 150 Bioabsorbable fiber 200 Heart 250 Atrial septum 252 Defect 300 Catheter 500 Delivery cable (operation wire)
510 Cable body 550 Outer tube (fluorine tube)
560 Hand-operated jig

Claims (3)

A medical material comprising a tube of a knitted tissue using a bioabsorbable wire and a delivery cable detachably joined to the tube, wherein when the medical material is housed in a catheter and delivered into a living body, a proximal end of the catheter is located outside the living body;
The cylindrical body is
The cylindrical body has a shape in which a cylindrical diameter of a substantially central portion is smaller than a cylindrical diameter of a first cylindrical portion and a second cylindrical portion which are other portions,
The first cylindrical portion is formed on a first end side, which is one end in a longitudinal direction of the cylindrical body, and the second cylindrical portion is formed on a second end side, which is the other end, with the approximately central portion as a center,
when the first end and the second end are separated from each other with the approximate central portion as the center and the tubular diameter of the other portion is reduced and the medical material is stored in the catheter, the second end side becomes the tip side of the catheter, and when the tubular body is removed from the catheter with the approximate central portion of the tubular body inside the catheter placed at the position of a defect in a living body, the tubular diameters of the first tubular portion and the second tubular portion, which are the other portions whose shapes were restricted by the inner wall of the catheter, expand to close the defect in the living body,
a cylindrical body-side joint portion is provided on the second end portion for joining a delivery cable that is passed from the second end portion through the approximately central portion and the first end portion to outside the living body ;
When the cylindrical body of the medical material is placed inside a living body and the end of the delivery cable of the medical material on the hand side opposite to the cylindrical body is taken outside the living body,
The delivery cable includes:
a cable main body having a tip end with a cable side joint portion joined to the tube side joint portion of the tube body, and having a length from the tube side joint portion to outside the living body;
an outer tube that is placed on the cable body so as to be slidable along the cable body, the outer tube having a length from a first end of the tube body to outside the body in a state in which the tube diameters of the first tube portion and the second tube portion are expanded to close the defect hole in the living body,
The medical material comprises:
the cylindrical body with the cylindrical body side joint and the cable side joint joined together, the cable main body, and the outer cylinder are housed within the catheter, the outer cylinder and the cable main body are led by the catheter to an outside of the living body where the outer cylinder and the cable main body can be operated, and the outer cylinder is exposed longer than the catheter outside of the living body so that the outer cylinder and the cable main body can be operated outside of the living body, and the cable main body is exposed longer than the outer cylinder,
13. The medical material according to claim 12, wherein when the tubular body is removed from the catheter with the approximate central portion positioned at the position of the defect, the delivery cable is operated to pull the second tubular portion out of the catheter and deploy it, and then the first tubular portion is further pulled out of the catheter and deployed, so that the length of the outer tube is the length from the first end of the tubular body to outside the organism in a state in which the defect in the organism is closed, and the outer tube exposed from the catheter outside the organism is slid along the cable main body toward the organism, and the first end is pressed toward the second end by an end face of the outer tube inside the organism, whereby the first tubular portion is removed from the catheter and deployed, and the first end and the second end approach each other with the approximate central portion as a center, so that the tubular diameters of the first tubular portion and the second tubular portion expand to close the defect . The medical material according to claim 1 , wherein the outer tube has a flange having an outer diameter smaller than the inner diameter of the catheter on an end surface that abuts against the first end of the cylindrical body . The cylindrical body side joint portion is a hollow cylindrical object having a female thread,
The cable-side joint portion is a male screw provided at a tip of the cable main body,
The cable body includes:
a hand-operated jig for use after the cylindrical body, which is joined by screwing the male thread into the female thread, the cable main body, and the outer tube are housed in a catheter and introduced into a living body, and a defect hole in the living body is closed by the cylindrical body,
3. The medical material according to claim 1 or 2, characterized in that a hand-operated tool is connected to a portion exposed outside the body beyond the catheter and the outer tube, which rotates the cable main body on its axis to release the threaded engagement between the male thread and the female thread, thereby detaching the cable main body from the tube.

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