JP2015039577A - Prosthetic valve, base material for forming prosthetic valve, and production procedure of prosthetic valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a prosthetic valve that can be transplanted to a site having short flowing-directional length such as a part between cardiac chambers, a base material for forming the prosthetic valve, and a production procedure of the prosthetic valve.SOLUTION: The prosthetic valve includes a cylindrical valve element 5 consisting of a connective tissue. A base end of the valve element 5 is defined as a fixing part 6. A string-like chorda tendinea 7 is extended from the tip end of the valve element 5. The fixing part 6 of the valve element 5 is fixed to a transplantation side. The tip end of the valve element 5 is fastened by the chorda tendinea 7. A fluid flowing to the tip end side pushingly expands the valve element 5 from the inside to open the valve element. The fluid flowing to the base end side smashes the valve element 5 from the outside to close the valve element.

Description

  The present invention relates to a prosthetic valve provided with a tubular valve element made of connective tissue, a base for forming an artificial valve, and a method for producing the artificial valve.

  There have been many studies on regenerative medicine in which cells, tissues, and organs lost due to illness and accidents are revived by artificial materials and cells. Normally, the body has a self-defense function, and when a foreign object such as a thorn enters a shallow position inside the body, it tries to push it out of the body, but when a foreign object enters a deep position inside the body, It is known that fibroblasts gather and sequester in the body by forming a capsule of connective tissue composed mainly of fibroblasts and collagen and covering foreign matter. A plurality of methods for forming a tubular living body tissue using living cells in the living body using the latter self-defense reaction have been reported (see Patent Documents 1 to 3).

  Patent Document 4 discloses a stent in which a tubular stent intermediate body is covered with a connective tissue layer, and a valve body is integrally formed with the connective tissue layer covering the stent intermediate body.

JP 2007-312821 A JP 2008-237896 A JP 2010-094476 A JP 2007-037763 (paragraph numbers 0012, 0037, 0081, FIG. 4)

  By the way, in the invention described in Patent Document 4, a valve body having a plurality of leaves is formed inside a tubular stent mainly placed in a blood vessel, and is placed in a vessel such as a blood vessel near the heart, a limb blood vessel, or an esophagus. It provides a valve function.

  On the other hand, an artificial valve that can be used as a valve located between chambers such as a mitral valve that partitions the left ventricle and the left atrium of the heart and a tricuspid valve that partitions the right and right chambers of the heart is required. It has been.

  An object of the present invention is to provide a prosthetic valve, a prosthetic valve-forming base material, and a prosthetic valve production method that can be transplanted to a site having a short length in the flow direction, such as between heart chambers.

  In order to achieve the above object, an artificial valve according to the present invention is provided with a cylindrical valve body made of connective tissue, and the base end portion of the valve body is fixed to a site where the artificial valve is transplanted. As a possible fastening portion, string-like chords are extended from a plurality of locations in the circumferential direction of the distal end portion of the valve body.

  According to the above configuration, the proximal end portion of the tubular valve body can be fixed to the transplant site, so that the artificial valve can be transplanted to a site with a short length in the flow direction, such as between the heart chambers. . Moreover, since a string-like chordae is extended from the tip of the valve body, the tip of the chord is fastened to the tip side of the part where the valve body is implanted, and the tip of the valve body is fastened. It is possible to prevent the distal end of the valve body from being pushed into the proximal end while being turned over by the flow pressure.

  As described above, the valve body is configured such that the proximal end portion thereof is fixed to the transplant site and the distal end portion is fastened with the chord, and when the fluid is about to flow from the proximal end side to the distal end side. The valve body is pushed open from the inside to open, and when trying to flow from the distal end side to the proximal end side, the valve body is crushed from the outside to close. Thereby, the artificial valve having the above configuration can prevent the flow from the distal end side to the proximal end side while allowing the flow from the proximal end side to the distal end side.

  Here, the “connective tissue” usually refers to a tissue mainly composed of collagen and formed in a living body. In the description of the present specification and claims, This is a concept including a tissue corresponding to a connective tissue formed in a living body when the tissue is formed in an environment outside the living body. In addition, the “thorn cord” in the prosthetic valve of the present invention is a concept that includes the same “connective tissue” as the “connective tissue” that constitutes the valve body. In the description, the term “thorn cord” is used as it is.

  Further, the valve body may be set to have a peripheral length on the distal end side smaller than that on the proximal end side. According to this configuration, since the valve body has a tapered shape toward the distal end side, the pressure of the fluid that is about to flow from the distal end side to the proximal end side can be directly applied to the outer surface of the valve body, and when the valve is closed The valve body can be easily crushed.

  Moreover, you may make it make the valve body thicken the fixation part of the base end rather than another site | part. According to this configuration, since the fastening portion of the valve body is thicker than other portions, the fastening portion can be thickened and reinforced without impairing the flexibility of the valve body.

  Moreover, you may make it embed a reinforcing material in the fastening part of the base end of the valve body. According to this configuration, since the reinforcing material is embedded in the fastening portion of the valve body, the fastening portion can be reinforced with the reinforcing material without impairing the flexibility of the valve body.

  The present invention also provides an artificial valve forming substrate for forming a connective tissue body that can be processed into an artificial valve on its surface by placing it in an environment where a biological tissue material exists. Specifically, a valve body forming portion that forms a processable part of a tubular valve body in the connective tissue body, and a string-like tendon extending from the distal end portion of the valve body in the connective tissue body A chordae forming portion that forms a portion that can be processed into a chord, and the valve body forming portion and the chordae forming portion are columnar adjacent to each other in the central axis direction.

  According to the above configuration, the base material is a columnar shape, and the valve body forming portion and the chordae forming portion are adjacent to each other in the central axis direction, so that the connective tissue formed on the surface of the chordae forming portion is processed into a string-like chordae By doing so, a string-like chord can be extended from the tip of the tubular valve body formed on the surface of the valve body forming portion.

  Here, the “biological tissue material” is a substance necessary for forming a desired biological tissue, such as fibroblasts, smooth muscle cells, endothelial cells, stem cells, ES cells, iPS cells, etc. Animal cells, various proteins (collagen, elastin), saccharides such as hyaluronic acid, and other various physiologically active substances existing in vivo such as cell growth factors and cytokines. The “biological tissue material” includes materials derived from mammals such as humans, dogs, cows, pigs, goats and sheep, birds, fish and other animals, or artificial materials equivalent thereto.

  In addition, “in the environment where biological tissue material is present” means in vivo (for example, limbs, mammals such as humans, dogs, cows, pigs, goats, sheep, birds, fish, and other animals). It represents the inside of an artificial environment containing a biological tissue material outside the living body of an animal).

  Furthermore, you may make it set the valve body formation part to make the circumference of the front end side smaller than the base end side. According to this configuration, a tapered valve body can be formed on the surface of the valve body forming portion toward the distal end side, and a valve body that can be easily crushed by the pressure of fluid when the valve is closed can be formed.

  In addition, a notch continuous in the circumferential direction is formed at the base end portion of the valve body forming portion, and a flange that forms a groove portion is provided by closing the base end side of the notch, and the flange is provided on the base end side of the valve body forming portion. It may be made to be detachable.

  According to this configuration, since the groove portion is formed at the base end portion of the valve body forming portion, the base end portion of the valve body formed on the surface of the valve body forming portion can be thicker than other portions. In addition, since the flange constituting the groove wall on the proximal end side of the groove portion is detachable, the valve body formed in the groove portion is formed by removing the flange from the valve body forming portion after forming the valve body on the surface of the valve body forming portion. Therefore, the connective tissue body can be easily taken out from the base material without the thickened portion being caught by the flange.

  The present invention also provides a method for producing a prosthetic valve having a tubular valve body made of connective tissue. Specifically, as an artificial valve production method step, an installation step of placing a columnar base material having a valve body forming portion and a chordae forming portion adjacent to each other in the central axis direction in an environment where biological tissue material exists; A forming step of forming a connective tissue around the substrate, a removing step of removing the substrate coated with the connective tissue from the environment, and a separating step of separating and removing the tubular connective tissue body from the substrate, A cutting step of cutting a site formed on the surface of the chordae forming part of the connective tissue body, and extending a string-like chordae from the tubular valve body formed on the surface of the valve body forming part, Is provided.

  According to the above configuration, after forming the connective tissue body using the columnar base material, the string-like chords are extended from the tubular valve body by the cutting step, so the base material having a complicated shape is used. Therefore, a string-like chord can be formed, and formation of a base material and formation of a connective tissue body using the base material can be facilitated.

  As described above, according to the present invention, the proximal end portion of the valve body can be fixed to the transplant site, and the distal end portion of the valve body can be fastened with a chord. The artificial valve can be implanted in a portion having a short length in the flow direction while preventing the push-in to the end side. As a result, the artificial valve can be transplanted to a site having a short length in the flow direction, such as between the heart chambers, for example, a mitral valve that partitions the left and right chambers of the heart, or the right and right chambers of the heart. Can be used as a valve located between the chambers such as a tricuspid valve.

The perspective view seen from the tip side of the artificial valve concerning the present invention Perspective view from the base end side of the artificial valve Longitudinal section showing attachment of prosthetic valve to the heart The perspective view which shows the valve closing state of an artificial valve Perspective view of an artificial valve without reinforcement It is a figure which shows the diameter adjustment of a fixation part, (a) shows an initial state, (b) shows a diameter reduction state. Perspective view of base material for artificial valve formation Diagram showing the procedure for producing an artificial valve Perspective view of the base material forming the artificial valve without reinforcement Perspective view of another form of artificial valve forming substrate It is a figure which shows the shape adjustment of the fastening part of the artificial valve produced using the base material of FIG. 10, (a) shows an initial state, (b) shows a deformation | transformation state. Still another form of artificial valve forming base material perspective view Still another form of artificial valve forming base material perspective view

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out a prosthetic valve, a prosthetic valve forming substrate, and a prosthetic valve production method according to the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 to 4, the artificial valve 1 can be transplanted to a site having a short length in the flow direction and is used, for example, as a mitral valve that partitions the left chamber 3 and the left atrium 4 of the heart 2. And a tubular valve body 5 made of connective tissue, the proximal end portion of the valve body 5 being a fastening portion 6 that can be fastened to a site where the artificial valve 1 is implanted, String-like chords 7 are extended from a plurality of locations in the circumferential direction.

  The valve body 5 has a substantially frustoconical cylindrical shape whose peripheral length on the distal end side is set to be smaller than that on the proximal end side, and the central hole 8 is pushed and widened by the pressure of the fluid trying to pass through the central hole 8. The central hole 8 is crushed and closed.

  The fastening part 6 is thicker than the other parts of the valve body 5 and is reinforced by embedding a reinforcing material 9, and fastens to the heart 2 or the like without impairing the flexibility of the valve body 5. It has sufficient strength.

  For example, the reinforcing material 9 is formed into a ring-like shape by connecting a plurality of strips 10 made of a polymer material with two thin shafts 11 oriented in the circumferential direction at each connection point. In addition, a plurality of fastening holes 12 for sewing the fastening portion 6 at the transplant site are formed. The thin shaft 11 is set to a strength that can be easily broken by applying a force from the outside of the fastening portion 6 in which the reinforcing material 9 is embedded, and the thin shaft 11 is reinforced while reinforcing the fastening portion 6 with the reinforcing material 9. The diameter and shape of the fastening portion 6 can be adjusted by breaking.

  As shown in FIG. 5, the artificial valve 1 is not necessarily provided with the reinforcing material 9, and the artificial valve 1 without the reinforcing material 9 can be employed.

  As shown in FIG. 6, the length of each thin shaft 11 is set to the length (a), and by breaking the thin shaft 11 and bringing the strips 10 closer to each other, the length (a) is obtained. The circumference of the reinforcing material 9 can be shortened within a corresponding range, and the reinforcing material 9 can be reduced in diameter from the initial diameter (d1) to the reduced diameter (d2). On the other hand, by breaking the thin shaft 11 and widening the interval between the strips 10, the peripheral length of the reinforcing member 9 can be lengthened and the diameter of the reinforcing member 9 can be increased. The shape of the fastening portion 6 can also be adjusted by appropriately bending at.

  The chords 7 are formed in a string-like and smooth tapered shape, and a total of four chords 7 are extended to the tip side one by one from four points set at substantially equal intervals in the tip of the valve body 5. When the artificial valve 1 is transplanted, the chordal tip 13 is fixed to the tip of the valve body 5. The tip of the valve body 5 is fastened to the transplanted site via the chords 7, and the attachment positions of the four chords 7 are set close to the top and bottom and left and right to set the valve body 5. Can be crushed up and down. The valve body 5 to be crushed up and down is configured such that the upper half is the front leaf 14 and the lower half is the rear leaf 15, and the front leaf 14 and the back leaf 15 are in contact with each other to close the valve. .

  The prosthetic valve 1 has, for example, a fastening part 6 of the valve body 5 fastened between the left chamber 3 and the left atrium 4 of the heart 2, and a chordal tip 13 of the chord 7 is connected to the chamber wall of the left chamber 3. The heart 2 is implanted as an artificial mitral valve (see FIG. 3). Here, FIG. 3 is a cross-sectional view of the heart 2, and shows a cross section in a vertical plane passing through the left ventricle 3, the left atrium 4, the right ventricle 16, the aorta 17, and the aortic valve 18.

  When the left ventricle 3 contracts, the prosthetic valve 1 implanted as a prosthetic mitral valve in the heart 2 applies blood pressure to the outer surface of the substantially frustoconical cylindrical valve body 5 to crush the central hole 8; The front leaflet 14 and the back leaflet 15 come into contact with each other to close the valve, thereby preventing blood flow from the left ventricle 3 toward the left atrium 4 (see FIG. 4). On the other hand, when the blood flow is going from the left atrium 4 to the left ventricle 3, the central hole 8 of the valve body 5 is expanded and opened by the blood flow.

  In this artificial valve 1, the distal end portion of the valve body 5 is fastened by the chord 7, so that when the valve is closed, the distal end portion of the valve body 5 is prevented from being pushed into the left atrium 4 by the blood pressure. The Furthermore, since the attachment positions of the upper left and lower left chords 7 are made closer and the attachment positions of the upper right and lower right chords 7 are made closer, the chords 7 are prevented from obstructing the valve 5 from closing. Is done.

  Next, the artificial valve forming base material 19 used when producing the artificial valve 1 as described above will be described.

  As shown in FIG. 7, the base material 19 is for forming a connective tissue body 20 that can be processed into the prosthetic valve 1 on its surface by placing it in an environment where biological tissue material exists. A valve body forming portion 21 that forms a processable portion on the tubular valve body 5 of the tissue body 20 and a string-like chord extending from the tip of the valve body 5 of the connective tissue body 20 7 and a chordal cord forming portion 22 that forms a processable portion, and the valve body forming portion 21 and the chordal cord forming portion 22 are adjacent to each other in the central axis direction, and are configured in a column shape as a whole.

  The valve body forming portion 21 has a circular base end section and a square with a diagonal section whose length is substantially the same as the diameter of the base end section, and smoothly connects the two cross sections. The peripheral length on the distal end side is set smaller than that on the proximal end side.

  A notch 23 that is continuous in the circumferential direction is formed at the base end of the valve body forming portion 21, and the base end side of the notch 23 is closed by a flange 24 to form a groove 25, which is accommodated in the groove 25. Thus, the reinforcing material 9 of the artificial valve 1 is arranged. The flange 24 is formed in a disc shape having a diameter substantially the same as the base end of the valve body forming portion 21, and a circular protrusion 26 protruding from one surface thereof is formed into a fitting hole that opens to the base end side of the valve body forming portion 21. It can be fitted and can be freely attached to and detached from the base end side of the valve body forming portion 21. In FIG. 7, reference numeral 27 denotes a knob for attaching and detaching the flange 24.

  The chordae forming part 22 is a rectangular parallelepiped having the same shape and the same size as the tip of the valve body forming part 21, and is formed adjacent to the tip side of the valve body forming part 21. A cut line forming groove 28 is formed on each side surface of the chord forming part 22 in the connective tissue body 20 formed on the surface of the chord forming part 22 for forming a cutting line when cutting the chord chond into the chord chord 7. Yes. The cutting line forming groove 28 is formed in a substantially arch shape so as to partition a tapered range near the corner of the chord forming part 22 from the central part.

  In order to increase the thickness of the corners of the valve body 5 and the chords 7 formed on the surface of the base material 19 at the corners of the valve body forming part 21 and the chords forming part 22 continuously in the central axis direction. A thickening groove 29 is formed. The thickened grooves 29 increase the thickness of the corner portions of the valve body 5 and the chord 7, thereby reinforcing the corner portion that tends to be a weak point portion of the valve body 5 and the chord 7.

  The material of the base material 19 has a strength (hardness) that does not greatly deform when embedded in a living body, has chemical stability, is resistant to a load such as sterilization, and stimulates the living body. A resin having no or little eluate is preferable, and examples thereof include, but are not limited to, a silicone resin and an acrylic resin. In addition, since the thickness of the artificial valve 1 is determined by the outer diameter of the base material 19, the diameter can be changed according to the target thickness.

  Next, a method for producing the artificial valve 1 using the artificial valve forming base material 19 as described above will be described.

  As shown in FIG. 8, in this production method, an “assembly process” in which the columnar base material 19 is assembled while the reinforcing material 9 is arranged in the groove portion 25, and the base material 19 is placed in an environment in which a biological tissue material exists. "Installation process", "Formation process" for forming the connective tissue 30 around the base material 19, "Extraction process" for taking out the base material 19 covered with the connective tissue 30 from the environment, and a cylindrical shape from the base material 19 The “separation process” in which the connective tissue body 20 is peeled and taken out, and the site formed on the surface of the chordae forming part 22 of the connective tissue body 20 is cut and formed on the surface of the valve body forming part 21 This includes a “cutting step” in which a string-like chord 7 is extended from the tubular valve body 5 formed.

  8, (a) to (d) show side views, and (e) and (f) show a cross-sectional view of the upper half and a side view of the lower half.

<Assembly process>
After covering the notch 23 at the base end of the base material 19 with the reinforcing material 9, the circular protrusion 26 is fitted into the fitting hole on the base end side of the valve body forming portion 21, and the base end side of the valve body forming portion 21. The flange 24 is attached to the base 19 and the base material 19 is assembled. Thereby, the base end side of the notch 23 is closed by the flange 24 to form the groove portion 25, and the reinforcing member 9 is disposed in the groove portion 25 (FIGS. 8A and 8B).

<Installation process>
The base material 19 is placed in an environment where the biological tissue material is present (FIG. 8B). The environment in which the biological tissue material exists includes in an animal's living body (for example, subcutaneously or intraperitoneally embedded) or in an artificial environment such as a solution in which the biological tissue material floats outside the animal's body. . As biological tissue materials, materials derived from other mammals such as humans, dogs, cows, pigs, goats, rabbits, sheep, birds, fish, other animals, or artificial materials can be used.

  When the base material 19 is implanted in an animal, it is performed with a minimum of incision under sufficient anesthesia, and the wound is sutured after implantation. As an embedding site of the base material 19, for example, intraperitoneal cavity having a volume for receiving the base material 19, or subcutaneous such as an extremity, a shoulder or a back, and an abdomen are preferable. In addition, it is preferable that the implantation is performed by a minimally invasive method and the spirit of animal welfare is respected, and is performed with a minimum of incision under sufficient anesthesia.

  In addition, when the base material 19 is placed in an environment where the biological tissue material is present, various culture conditions are prepared and cell culture may be performed in a clean environment according to a known method.

<Formation process>
After the installation step, a predetermined time elapses, whereby a film-like connective tissue 30 is formed around the base material 19 (FIG. 8C). The connective tissue 30 enters the groove portion 25 to form the thickened fastening portion 6, and the reinforcing material passes through the gap between the groove wall of the groove portion 25 and the reinforcing material 9 and the fastening hole 12 of the reinforcing material 9. The reinforcing material 9 is embedded in the fastening portion 6.

  Further, when the connective tissue 30 enters the cutting line forming groove 28, the cutting line 31 of the connective tissue body 20 is formed, and when the connective tissue 30 enters the thickening groove 29, the corner portion of the connective tissue body 20 is formed. Will be reinforced. The connective tissue 30 is composed of an extracellular matrix such as fibroblasts and collagen.

<Removal process>
After the connective tissue 30 is sufficiently formed through the formation process for a predetermined time, a take-out process for taking out the base material 19 from the environment in which the biological tissue material exists is performed. The base material 19 taken out from the environment in which the biological tissue material exists is covered with a film of the connective tissue 30 on the entire surface including both end faces thereof.

<Separation process>
The connective tissue 30 on the surface of both ends of the base material 19 is removed (FIG. 8D), and then the flange 24 is removed from the proximal end side of the valve body forming portion 21 and the fastening portion 6 remains fitted. The base end side of the groove portion 25 is opened, and the remaining connective tissue 30 covering the peripheral surface of the base material 19 is peeled off from the surface of the base material 19 as a cylindrical connective tissue body 20 (FIG. 8 (e )).

<Cutting process>
The connective tissue body 20 is cut along the cutting line 31 to form the string-like chords 7, whereby the artificial valve 1 in which the chords 7 are extended from the valve body 5 is obtained (FIG. 8 (f)). ).

  In the case of xenotransplantation of the produced artificial valve 1, it is preferable to perform immunogen removal treatment such as decellularization treatment, dehydration treatment, and fixation treatment in order to prevent rejection after transplantation. Examples of decellularization include ultrasonic treatment, surfactant treatment, and enzyme treatment such as collagenase to elute and wash the extracellular matrix. Dehydration methods include methanol, ethanol, isopropyl alcohol, etc. There is a method of washing with a water-soluble organic solvent, and as a method of fixing, there is a method of treating with an aldehyde compound such as glutaraldehyde or formaldehyde.

  In addition, as shown in FIG. 9, when producing the artificial valve 1 without the reinforcing material 9, the base material 19 is assembled without arranging the reinforcing material 9 in the groove portion 25, and the connective tissue 30 is formed around the base material 19. Thus, the artificial valve 1 may be produced by the same procedure as described above.

  Further, the present invention is not limited to the above-described embodiments, and appropriate modifications can be made within the scope of the present invention. For example, as shown in FIG. 10, as the artificial valve forming base material, a flat base material 32 can be adopted instead of the base material 19 having a circular base end section and a square front end section.

  The valve body forming portion 33 of the base material 32 has an oval base end section and a rectangular shape with a tip section inscribed in the ellipse of the base end section. The peripheral length on the distal end side is set smaller than that on the proximal end side.

  The chord forming part 34 of the base material 32 is a rectangular parallelepiped having the same shape and the same size as the tip of the valve body forming part 33. Double grooves are formed on the side surface of the base material 32, the inner groove of the arch shape is a cutting line forming groove 35, and the outer groove of the arch shape reinforces the side edge of the chord chord 7 with increased thickness. The thickening groove 36 is formed. The chords formed by cutting the connective tissue body 20 along the cutting line formed by the cutting line forming groove 35 by using the thickening line formed by the thickening groove 36 outside the arch shape as a cutting line. A chord chord narrower than 7 can be formed.

  The prosthetic valve 1 formed using the base material 32 has the chords forming portions 34 having a rectangular cross section, so that the chords 7 are arranged at unequal intervals, and the proximal ends of the upper and lower chords 7 in the valve-opened state. Can be made close to each other, and the resistance of the chord 7 when the valve body 5 is crushed up and down to close the valve can be further reduced.

  As shown in FIG. 11, the reinforcing member 37 in the case of employing the base material 32 is deformed from an elliptical initial state (see FIG. 11A) to a substantially circular shape by breaking the thin shaft 11. Further, the diameter (d) of the reinforcing member 37 can be adjusted by adjusting the distance between the strips 10.

  Further, the reinforcing members 9 and 37 are not limited to the polymer material, and may be formed from other materials such as sponge and metal, and the reinforcing members 9 and 37 may not be provided in the fastening portion 6. . For example, as shown in FIG. 12, when the artificial valve is produced, the base material 32 is used without being provided with the reinforcing material 37 in the groove portion 25, so that the reinforcing material 37 is not thickly reinforced. The fastening part can be formed.

  Further, the artificial valve does not necessarily need to be thickened at its fastening part, and the fastening part may be formed to a thickness similar to that of other parts. In this case, as shown in FIG. 13, instead of the base materials 19 and 32, an artificial valve can be formed using a base material 38 that does not have the groove portion 25 at the base end portion of the valve body forming portion 33.

  A plurality of valve body cutting line forming grooves 39 a, 39 b, 39 c, 39 d, 39 e that are continuous in the circumferential direction are formed at the proximal end portion of the valve body forming portion 33 of the base material 38. A cutting line is formed. The size of the valve body 5 can be adjusted by cutting the connective tissue body 20 along a cutting line appropriately selected from a plurality of cutting lines according to the transplant site. Moreover, the opening shape of the fastening part of the valve body 5 can also be adjusted by cutting the valve body 5 diagonally using a plurality of cutting lines as marks.

  An arch-shaped cutting line forming groove 40 is formed in the chord forming part 34 of the base material 38, and the vicinity of the arch-shaped top part branches into a plurality of branch grooves 40a, 40b, 40c, 40d, 40e. A cutting line that is formed and branches into a plurality of connective tissue bodies 20 is formed. The size of the valve body 5 and the length of the chordal cord 7 can be adjusted by cutting the connective tissue body 20 along the appropriately selected cutting line according to the transplant site from among the branched cutting lines. .

  The prosthetic valve 1 is not limited to being used as an artificial mitral valve. For example, a tricuspid valve that partitions the right ventricle and the right atrium of the heart by appropriately setting the number of the chords 7 and the fixing position thereof. It can also be used as another artificial valve.

DESCRIPTION OF SYMBOLS 1 Artificial valve 2 Heart 3 Left ventricle 4 Left atrium 5 Valve body 6 Fastening part 7 Tendon cord 8 Central hole 9 Reinforcement material 10 Band plate 11 Fine shaft 12 Fastening hole 13 Tipon chord 14 Front leaflet 15 Rear leaflet 16 Right Chamber 17 Aorta 18 Aortic valve 19 Base material 20 Connective tissue body 21 Valve body formation part 22 Chondrogenesis part 23 Notch 24 Flange 25 Groove part 26 Circular protrusion 27 Knob 28 Cutting line formation groove 29 Thickening groove 30 Connective tissue 31 Cutting line 32 Substrate 33 Valve body forming portion 34 Chondrite formation portion 35 Cutting line forming groove 36 Thickening groove 37 Reinforcing material 38 Base materials 39a, 39b, 39c, 39d, 39e Valve body cutting line forming groove 40 Cutting line forming groove 40a, 40b, 40c, 40d, 40e Branch groove

Claims (8)

  A tubular valve body made of connective tissue, wherein the base end portion of the valve body is a fastening portion that can be fastened to a site where the artificial valve is transplanted, and a plurality of locations in the circumferential direction of the distal end portion of the valve body A prosthetic valve characterized by extending a string-like chord from   The artificial valve according to claim 1, wherein the valve body is set to have a peripheral length on a distal end side smaller than a proximal end side.   3. The artificial valve according to claim 1, wherein the valve body has a thickness of the fastening portion at a base end thereof that is thicker than other portions.   The artificial valve according to claim 1, 2, or 3, wherein a reinforcing material is embedded in the fastening portion of the base end of the valve body. A base material for forming a connective tissue body that can be processed into an artificial valve on its surface by placing it in an environment where biological tissue material exists,
A valve body forming portion that forms a portion that can be processed into a tubular valve body of the connective tissue body, and a string-like chord extending from a distal end portion of the valve body of the connective tissue body A base for artificial valve formation, comprising: a chordae forming part that forms a processable part, wherein the valve body forming part and the chordae forming part are formed in a columnar shape adjacent in a central axis direction.   6. The artificial valve forming substrate according to claim 5, wherein the valve body forming portion is set to have a peripheral length on a distal end side smaller than a proximal end side.   A notch continuous in the circumferential direction is formed in the base end portion of the valve body forming portion, and a flange is provided to close the base end side of the notch to form a groove portion, and the flange is formed on the valve body forming portion. The base material for artificial valve formation according to claim 5 or 6, wherein the base material is detachable from the base end side. A method for producing a prosthetic valve having a tubular valve body made of connective tissue,
An installation step of placing a columnar base material having a valve body forming portion and a chord forming portion adjacent to each other in the central axis direction in an environment where biological tissue material exists, and a forming step of forming a connective tissue around the base material A step of taking out the base material coated with connective tissue from the environment, a step of separating and taking out the tubular connective tissue body from the base material, and formation of chordae in the connective tissue body A cutting step of cutting a part formed on the surface of the part and extending a string-like chord from a tubular valve body formed on the surface of the valve body forming part, To produce artificial valves.

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