JP5907536B2 - Artificial blood vessel - Google Patents

Description

  The present invention relates to an artificial blood vessel used for aortic root replacement.

For example, aortic annuloplasty may be performed with aortic root replacement for preserving the self-aortic valve in patients who have no lesion in the aortic valve itself.
In the David method, which is a self-aortic valve-sparing aortic root replacement, the Valsalva sinus is excised and replaced with an artificial blood vessel, and three commissures lifted inside thereof are sewn to the artificial blood vessel.

  Here, as an artificial blood vessel used for the David method, as shown in FIG. 7, a first portion 110 made of a tubular knitted fabric in which a spiral lateral fold 115 is formed, and a vertical fold 125 extending in the tube axis direction are formed. An artificial blood vessel is proposed that includes a second portion 120 made of a tubular knitted fabric and a third portion 130 made of a tubular knitted fabric formed with a spiral lateral fold 135 (for example, Patent Document 1). reference).

The second portion 120 of the artificial blood vessel shown in FIG. 7 is a portion that replaces the Valsalva sinus, and has an inner diameter larger than that of the distal side, approximating the shape of the Valsalva sinus.
Thereby, for example, it is avoided that the leaflet of the aortic valve contacts the inner wall of the artificial blood vessel (second portion 120), and a smooth opening / closing state of the aortic valve can be ensured.

US Patent Publication 2001/49553

(1) However, when a vertical fold is formed in a portion (second portion) that replaces the Valsalva sinus as in the artificial blood vessel described in Patent Document 1, the commissural portion is formed by the vertical fold. There is a problem that the sewing operation becomes extremely difficult.

(2) When blood is flowed through the lumen of the artificial blood vessel after the operation, the vertical folds formed in the artificial blood vessel (second portion) extend to expand (expand) the diameter of the artificial blood vessel. However, at this time, each of the commissures sewn inside the artificial blood vessel (second portion) is subjected to a tensile force in the circumferential direction due to the extension of the longitudinal folds, and the artificial blood vessel (second portion). ) Expands in diameter, and a radial tensile force acts. As a result, the commissure is pulled. Here, when uneven pulling occurs in the three commissures, for example, when large pulling occurs only in one commissure, the shape of the aortic valve optimized by surgery and the opening / closing operation thereof are The surgical design cannot be maintained because it is seriously damaged and causes blood regurgitation.

The present invention has been made based on the above situation.
A first object of the present invention is to provide an artificial blood vessel that can easily perform a sewing operation of a commissure portion in aortic root replacement.

  The second object of the present invention is that the circumferential and radial tensile forces are hardly applied to each of the sewn commissures even when blood is flowed by applying blood to the lumen after surgery, An object of the present invention is to provide an artificial blood vessel that can maintain the shape and opening / closing operation of an aortic valve optimized by surgery.

(1) The artificial blood vessel of the present invention is an artificial blood vessel provided with a portion (second portion described later) for replacing Valsalva sinus in aortic root replacement,
A first portion made of a tubular knitted fabric in which spiral or plural concentric transverse folds are formed;
And a second portion made of a tubular knitted fabric having a tube axis common to the first portion and formed with a plurality of vertical folds extending in the tube axis direction,
In the second portion, three vertical fold forming portions where the vertical folds are formed and three flat portions where the vertical folds are not formed are alternately arranged along the circumferential direction. It is characterized by that.

According to the artificial blood vessel having such a configuration, since vertical creases are not formed in the three flat portions in the second portion, the sewing portions are sewn by sewing each of the commissure portions to the flat portion. Operation can be performed easily.
In addition, even if blood pressure is applied to the lumen after surgery, the flat portion where no vertical folds are formed does not exert a tensile force in the circumferential direction on the commissure portion sewn on the flat portion. . Further, the diameter of the flat part when the blood pressure is applied is sufficiently smaller than the degree of diameter expansion of the vertical crease forming part, so that the diameter acting on the commissures sewn on the flat part The tensile force in the direction is also sufficiently small. Therefore, it is possible to effectively prevent the commissures from being pulled by these tensile forces, and to reliably maintain the shape and opening / closing operation of the aortic valve optimized by the operation.

(2) In the artificial blood vessel of the present invention, in the cross-sectional view of the second portion, the flat portion is arranged at an angular interval (θ ₁ ) of 120 ° ± 5 °, and the width of the flat portion (the length of the arc) central angle corresponding to) (theta ₂₎ is preferably a 20 to 60 °.

  According to the artificial blood vessel having such a configuration, each of the three commissures having a constant width (usually 5 to 8 mm) and formed at substantially equal angular intervals (120 ° ± 5 °) is formed as a flat portion. On the other hand, it can be sewn easily and reliably.

(3) In the artificial blood vessel of the present invention, it is preferable that a reference line indicating each position of the flat portion (a position where the commissure portion should be sewn) is formed.

(4) In particular, it is preferable that the reference lines are formed on both sides of the flat portion (boundary between the flat portion and the vertical fold forming portion).

  According to the artificial blood vessel having such a configuration, the position of each flat portion can be easily confirmed, and the commissure portion can be easily aligned with the flat portion.

(5) In the artificial blood vessel of the present invention, the second portion is formed of a tubular knitted fabric having a seamless structure formed by weaving warps extending in the tube axis direction of the second portion and wefts extending in the circumferential direction. It is preferable.

According to the artificial blood vessel having such a configuration, since there is no seam in the second portion that hinders the sewing operation, the sewing operation of the commissure portion can be performed more easily.
Further, by weaving a plurality of colored (3 or 6) warp yarns at a predetermined interval, a reference line indicating each position of the flat portion can be easily formed by the warp yarns.

(6) In the artificial blood vessel of (5), it is preferable that the length of the warp constituting the flat portion is shorter than the length of the warp constituting the vertical fold forming portion.

  According to the artificial blood vessel having such a configuration, when blood pressure is applied to the lumen after the operation, the lumen shape of the second portion can be further approximated to the shape of the Valsalva sinus.

According to the artificial blood vessel of the present invention, the sewing operation of the commissure portion can be easily performed in the aortic root replacement.
Further, even if blood is flowed by applying blood through the lumen of the artificial blood vessel after surgery, circumferential and radial tensile forces act on each of the commissures sewn on the flat part of the second part. Therefore, the shape and opening / closing operation of the aortic valve optimized by surgery can be maintained.
Furthermore, by applying blood pressure to the lumen after surgery, a lumen having a shape very close to the Valsalva sinus can be formed.

It is a side view which shows the artificial blood vessel which concerns on one Embodiment of this invention. It is sectional drawing (AA sectional drawing of FIG. 1) which shows typically the cross section of the artificial blood vessel shown in FIG. FIG. 2 is a side view showing a part of the artificial blood vessel shown in FIG. 1 (a part used for replacement of Valsalva sinus). It is sectional drawing which shows typically the state by which the commissure part is sewn inside a part of artificial blood vessel shown in FIG. It is sectional drawing which shows typically a state when blood pressure is applied to the lumen of the artificial blood vessel after the operation. It is a figure which shows typically the state which expand | deployed some artificial blood vessels which concern on other embodiment of this invention. It is a side view which shows the conventionally well-known artificial blood vessel used for aortic root replacement.

<First Embodiment>
Hereinafter, the artificial blood vessel of the present invention will be described in detail with reference to the drawings.
The artificial blood vessel 100 of this embodiment shown in FIG. 1 and FIG. 2 is an artificial blood vessel used for the David method (David1 Reimplantation Procedure) which is a self-aortic valve-sparing aortic base replacement.

  The artificial blood vessel 100 includes a first portion 10 made of a tubular knitted fabric in which a spiral horizontal fold 15 is formed, and a first knitted fabric made of a tubular knitted fabric in which a plurality of vertical folds 25 extending in the tube axis direction are formed. 2 parts 20 and the 3rd part 30 which consists of a tubular knitted fabric in which the spiral horizontal crease 35 was formed, The 3rd crease formation in which the vertical crease 25 was formed in the 2nd part 20 The portions (211, 212, 213) and the three flat portions (201, 202, 203) where no vertical folds are formed are alternately arranged along the circumferential direction.

As shown in FIG. 1, the first portion 10, the second portion 20, and the third portion 30 of the artificial blood vessel 100 have a common tube axis.
In FIG. 1, reference numeral 40 denotes a branch pipe (feeding blood vessel) made of a tubular knitted fabric in which a spiral horizontal fold 45 is formed. The branch pipe 40 is connected to the first portion 10 on the proximal end side, and is connected to, for example, an artificial lung on the distal end side.

  As the tubular knitted fabric constituting the artificial blood vessel 100 (the first portion 10, the second portion 20, the third portion 30, and the branch pipe 40), a tubular product made of a woven fabric or a knitted fabric of thermoplastic resin fibers can be used. A plain woven fabric of thermoplastic resin fibers can be suitably used. The wall thickness of the tubular knitted fabric is preferably 1 mm or less, more preferably 0.3 to 0.7 mm.

  Examples of the thermoplastic resin that forms the thermoplastic resin fiber include polyolefins such as polyethylene, polypropylene, and ethylene-α-olefin copolymers, polyamides, polyurethanes, polyethylene terephthalate, polybutylene terephthalate, polycyclohexane terephthalate, polyethylene-2,6- Examples thereof include polyesters such as naphthalate and fluororesins such as PTFE and ETFE. Of these, polyesters such as polyethylene terephthalate, fluorine resins such as PTFE and ETFE, which are chemically stable and have good durability and little tissue reaction, are preferred, particularly preferably a weight average molecular weight of 10,000 to 200,000. It is a polyester having a weight average molecular weight of 30,000 to 100,000.

As the thermoplastic resin fiber, a thread in which several to several hundreds of monofilaments of 0.5 to 5 denier are twisted can be used.
The thermoplastic resin fiber may be coated with an antithrombotic material such as heparin, collagen, acetylsalicylic acid, gelatin or the like.

  A spiral lateral fold 15 is formed in the first portion (main pipe portion) 10 of the artificial blood vessel 100 of the present embodiment. The first portion 10 in which the horizontal fold 15 is formed is resistant to expansion and contraction and bending, and easily adapts to the blood vessel shape of the human body.

  It is preferable that the height of the horizontal fold 15 in the first portion 10 (the height difference between the peak and the valley) is 0.5 to 3 mm. The pitch of the horizontal folds 15 is preferably 2 to 4 mm.

It is preferable that the internal diameter of the 1st part 10 is 22-34 mm, More preferably, it is 24-32 mm. Here, the inner diameter of the first portion 10 is an apparent inner diameter based on the valley of the horizontal fold 15.
The length of the first portion 10 (the length in the tube axis direction) is, for example, 100 to 800 mm, and preferably 200 to 600 mm.

  As shown in FIG. 2, in the second portion 20 of the artificial blood vessel 100 of the present embodiment, vertical fold forming portions (211, 212, 213) in which a plurality of vertical folds 25 extending in the tube axis direction are formed, Such flat portions (201, 202, 203) where no vertical folds are formed are alternately arranged along the circumferential direction (vertical fold forming portion 211, flat portion 201, vertical fold forming portion 212, flat portion 202. , Vertical crease formation part 213 and flat part 203).

  The three flat portions (201, 202, 203) arranged in the second portion 20 of the artificial blood vessel 100 are regions for sewing the commissures in the aortic root replacement.

In the cross-sectional view of the second portion 20 shown in FIG. 2, the flat portion arrangement angle interval (θ ₁ ) is preferably 120 ° ± 5 °, and 120 ° is a preferable example.
Moreover, it is preferable that the width | variety (length of the circular arc which shows a flat part in FIG. 2) (w) of a flat part is 6-12 mm, More preferably, it is 8-10 mm.
In addition, the central angle (θ ₂ ) corresponding to the width (w) of the flat portion is preferably 20 to 60 °, more preferably 30 to 50 °.

  Accordingly, each of the three commissures having a constant width (usually 5 to 8 mm) and formed at substantially equal angular intervals (intervals of 120 ° ± 5 °) is replaced with the flat portion of the second portion 20. Each can be sewn easily and reliably.

A plurality of vertical folds 25 extending in the tube axis direction are formed in each of the vertical fold forming portions (211, 212, 213) of the second portion 20.
The height of the vertical folds 25 formed in each of the vertical fold forming portions (the difference in height between the peak portion and the valley portion) is not particularly limited, but is preferably 0.5 to 3 mm.
Further, the pitch of the vertical folds 25 is not particularly limited, but is preferably 2 to 4 mm.

The inner diameter of the second portion 20 is preferably 1.0 to 1.6 times, more preferably 1.0 to 1.5 times the inner diameter of the first portion 10. Here, the inner diameter of the second portion 20 is an apparent inner diameter based on the valley of the vertical fold 25. That is, the second portion 20 may have an inner diameter that is larger than the inner diameter of the first portion 10 in a state where no pressure is applied to the inner cavity thereof.
The length of the second portion 20 (the length in the tube axis direction) is, for example, 20 to 40 mm, and preferably 20 to 30 mm.

Reference lines 27 are formed on both sides of the flat portion (201, 202, 203) of the second portion 20 (boundary with the vertical fold forming portion). Here, the reference line 27 can be formed by weaving a colored thread into the second portion 20.
The reference line 27 makes it easy to check the position of each flat part (201, 202, 203) and also makes it easy to check the width of each flat part (position where the commissure part should be sewn). The commissural part can be easily aligned with the part.

The second portion 20 of the artificial blood vessel 100 is made of a seamless knitted fabric (woven fabric) formed by weaving warps extending in the tube axis direction and wefts extending in the circumferential direction.
Since the seam that prevents the sewing operation is not present in the second portion 20, the sewing operation of the commissure portion can be performed more easily.
Further, when weaving the second portion 20, the reference line 27 made of colored warp can be easily formed by weaving six colored warps at a predetermined interval.

The third portion 30 of the artificial blood vessel 100 is connected to the second portion 20.
The third portion 30 of the artificial blood vessel 100 is a portion that is sewn to a biological blood vessel (aortic annulus) in the self-aortic valve-sparing aortic base replacement, and the third portion 30 has a spiral lateral fold 35. Is formed.
The height of the horizontal fold 35 formed in the third portion 30 (the difference in height between the peak and the valley) and the pitch of the horizontal fold 35 are the same as those of the horizontal fold 15 formed in the first portion 10. . Further, the inner diameter of the third portion 30 is also the same as the inner diameter of the first portion 10.
In addition, the horizontal fold 35 in the 3rd part 30 is not an essential structure, and the internal diameter of the 3rd part in which the horizontal fold is not formed shall be 24-40 mm, for example, Preferably it is 26-38 mm.
The length of the third portion 30 (the length in the tube axis direction) is, for example, 5 to 25 mm, and preferably 10 to 20 mm.

In the self-aortic valve-sparing aortic root replacement, a part of the artificial blood vessel 100 as shown in FIG. 3, that is, a part of the first part 10 (a part near the second part 20) and the whole of the second part 20. And the tubular part which consists of a part of 3rd part 30 (proximal part of the 2nd part 20) is used in order to replace a Valsalva sinus.
The remaining part of the first portion 10 (including the branch pipe 40) is used for surgery on the peripheral side of the aortic base.
In addition, you may use the tubular part which consists of the whole 2nd part 20 and a part of 3rd part 30, and does not have the 1st part 10 in order to replace a Valsalva sinus.

The length (length in the tube axis direction) of a part of the first portion 10 constituting a part of the artificial blood vessel 100 shown in FIG. 3 is, for example, 20 mm or less.
In addition, the length (length in the tube axis direction) of a part of the third portion 30 that constitutes a part of the artificial blood vessel 100 is, for example, 5 to 25 mm.

In the self-aortic valve-sparing aortic root replacement (David method), the Valsalva sinus is excised and replaced with a part of the artificial blood vessel 100 shown in FIG. 3 (hereinafter simply referred to as “artificial blood vessel”). Next, inside the artificial blood vessel in which the Valsalva sinus was replaced, three commissures were lifted, and as shown in FIG. 4, each of these commissures (C 1, C 2, C 3) Each flat part (201, 202, 203) is sewn.
At this time, the flat portions (201, 202, 203) are not formed with vertical folds that hinder the sewing operation of the commissure portions, and therefore the commissure portions can be easily sewn to each of the flat portions. . In addition, a part (root part) of the commissure part may be sewn on the vertical crease formation part.

After the sewing operation of the commissure portion with respect to the second portion 20 (flat portion) of the artificial blood vessel, the left and right coronary arteries (not shown) are sewn to the second portion 20 (longitudinal fold forming portion) according to a conventional method. .
Thereafter, the artificial blood vessel (first portion 10) in which the commissure and coronary artery are sewn in the second portion 20 is sutured to a peripheral biological blood vessel (ascending aorta) or an artificial blood vessel replacing the blood vessel to complete the operation. To do.

  After the operation, the vertical folds 25 formed in the vertical fold forming portions (211, 212, 213) of the second portion 20 are obtained by flowing blood through the lumen of the artificial blood vessel and applying a blood pressure (for example, 120 mmHg). As shown in FIG. 5, the diameter of the vertical fold forming portion located outside the three leaflets (V1, V2, V3) is greatly expanded.

On the other hand, as shown in FIG. 5, the diameters of the flat portions (201, 202, 203) where no vertical folds are formed are hardly changed (expanded).
As a result, the shape of the cross section (cross section) of the second portion 20 after the blood pressure is applied is very close to the shape of the cross section (cross section) of the Valsalva sinus where the outside of the three leaflets protrudes. . An artificial blood vessel (second portion 20) having such a cross-sectional shape is preferable from the viewpoint of hemodynamics.

  Further, as shown in FIG. 5, the flat portions (201, 202, 203) of the second portion 20 are not sewn up even if blood pressure is applied to the lumen, and are sewn to each of them. The pulling force in the circumferential direction and the radial direction is hardly applied to the commissures (C1, C2, C3), and the commissures are not pulled.

According to the artificial blood vessel 100 of the present embodiment, in the self-aortic valve-sparing aortic base replacement, the commissures (C1, C2, C2, C2, C2) are formed on the flat portions (201, 202, 203) of the second portion 20 where the vertical folds are not formed. Since C3) is sewn, the sewing operation can be easily performed.
Further, even if blood is flowed through the lumen of the artificial blood vessel 100 after the operation to apply blood pressure, the commissures (C1, C2, C3) sewn on the flat portions (201, 202, 203) of the second portion 20 are applied. Since pulling does not occur, the shape and opening / closing operation of the aortic valve optimized by the operation can be reliably maintained.
Furthermore, by applying a blood pressure to the lumen of the artificial blood vessel 100 to expand the second portion 20 (vertical fold forming portion), a lumen having a shape very close to the Valsalva sinus can be formed.

Second Embodiment
In the second portion made of the seamless knitted tubular woven fabric, the length of the warp constituting the flat portion can be made shorter than the length of the warp constituting the longitudinal fold forming portion.

FIG. 6 schematically shows a part of the artificial blood vessel thus produced.
In the developed shape shown in FIG. 6, the boundary line between the second part 70 and the first part 60 and the boundary line between the second part 70 and the third part 80 are not straight lines. The center of the flat part (center in the circumferential direction) is a concave curve.
Further, the boundary line between the vertical crease forming portions (711, 712, 713) and the flat portions (701, 702, 703) is not a straight line, and the center of the flat portion of the second portion 70 (the center in the tube axis direction) is It is a concave curve.

According to the second portion 70 having such a developed shape, when the pressure (blood pressure) is applied to the inner cavity, compared to the second portion in which the boundary line is a straight line, vertical folds are formed. It is possible to sufficiently suppress the flat portion from increasing in diameter as the portion expands.
In addition, the vertical cross-sectional shape of the second portion 70 (vertical crease forming portion) when pressure (blood pressure) is applied to the lumen is smooth, with the center of the vertical crease forming portion (center in the tube axis direction) being the most expanded. Can be made into a curved shape.
As a result, the lumen shape of the second portion 70 when blood pressure is applied can be made more approximate to the shape of the Valsalva sinus.

In addition, as a method of manufacturing an artificial blood vessel having a developed shape as shown in FIG. 6, the material for forming the second portion 70 is preset (pre-molded) into a predetermined three-dimensional shape, and both end portions of the tubular material are formed. Is cut along a plane perpendicular to the tube axis direction to produce a tubular knitted fabric constituting the second portion 70, and the first portion 60 and the third portion 80 are formed on each of both end edges of the tubular knitted fabric. A method of suturing can be mentioned.
By cutting the tubular material preset in a predetermined three-dimensional shape as described above, a tubular knitted fabric is produced in which the length of the warp constituting the flat portion is shorter than the length of the warp constituting the longitudinal fold forming portion. can do. In this tubular knitted fabric, the lengths of the warp yarns constituting the longitudinal crease forming portion and the warp yarn lengths constituting the flat portion may not all be the same.

  As mentioned above, although embodiment of this invention was described, the artificial blood vessel of this invention is not limited to these, A various change is possible.

For example, a seam may be formed in the second portion by manufacturing the second portion of the artificial blood vessel of the present invention by a conventionally known method as described in Patent Document 1.
Further, the number of reference lines formed in the second portion to indicate the position of each flat portion may be three.
Further, the reference line may be formed by printing or the like.
Further, a reference line may be formed in a component other than the second portion.
It may also be used for aortic root replacement, including replacing a self-aortic valve with a prosthetic valve.

DESCRIPTION OF SYMBOLS 100 Artificial blood vessel 10 1st part 15 Horizontal fold 20 2nd part 201,202,203 Flat part 211,212,213 Vertical fold formation part 25 Vertical fold 30 3rd part 35 Horizontal fold 40 Branch pipe 45 Horizontal fold 60 1st part 70 Second portion 701, 702, 703 Flat portion 711, 712, 713 Vertical fold forming portion 80 Third portion

Claims (6)

An artificial blood vessel having a portion that replaces the Valsalva sinus in aortic root replacement,
A first portion made of a tubular knitted fabric in which spiral or plural concentric transverse folds are formed;
And a second portion made of a tubular knitted fabric having a tube axis common to the first portion and formed with a plurality of vertical folds extending in the tube axis direction,
In the second portion, three vertical fold forming portions each having a plurality of vertical folds and three flat portions having no vertical folds are alternately arranged along the circumferential direction. An artificial blood vessel characterized by being arranged. In a cross-sectional view of the second portion, the flat portion is disposed at an angular interval (θ ₁ ) of 120 ° ± 5 °, and a central angle (θ ₂ ) corresponding to the width of the flat portion is 20 to 60 °. The artificial blood vessel according to claim 1, wherein the artificial blood vessel is provided.   The artificial blood vessel according to claim 1 or 2, wherein a reference line indicating each position of the flat portion is formed.   The artificial blood vessel according to claim 3, wherein the reference line is formed on both sides of each of the flat portions.   The said 2nd part consists of a tubular knitted fabric of the seamless structure formed by weaving the warp which extends in the pipe-axis direction of the said 2nd part, and the weft which extends in the circumferential direction. 4. The artificial blood vessel according to any one of 4.   The artificial blood vessel according to claim 5, wherein the length of the warp constituting the flat portion is shorter than the length of the warp constituting the longitudinal fold forming portion.

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