JP2016158765A - Medical-use multilayer cylindrical body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a medical-use multilayer structure that can satisfactorily regenerate an inner membrane, an intermediate membrane and an outer membrane of a vascular wall when applied to an artificial blood vessel.SOLUTION: An artificial blood vessel 100 that is an example of medical-use multilayer structures is a cylindrical body consisting of two nonwoven fabric layers and used for regenerative medicine, in which the blood vessel includes: a hollow cylindrical inner layer 110 which is manufactured by using bioabsorbable polymer, and constituted of a nonwoven fabric layer made of fiber having a fiber diameter at 20 μm or less; and a hollow cylindrical outer layer 120 which is provided outside the inner layer 110, manufactured by using bioabsorbable polymer having a composition with difference from the bioabsorbable polymer of the inner layer 110, and constituted of a nonwoven fabric layer made of fiber thicker than the fiber diameter of the fiber of the inner layer 110.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a medical material, and particularly relates to a cylindrical medical material suitable for an artificial blood vessel or the like. The cylindrical body is a pipe-shaped or tube-shaped hollow cylindrical shape and will be described below by exemplifying an artificial blood vessel. However, the medical multilayered tubular body according to the present invention is limited to an artificial blood vessel. Is not to be done.

  Arteriosclerotic lesions that occur due to various causes such as aneurysms and diabetes are one of the important lifestyle-related diseases, and in the advanced stage, stenotic blood vessels are often replaced with artificial blood vessels by surgery. Such an artificial blood vessel is required not only to leak not only blood cells but also plasma, but also to have various functions of blood vessels. The various functions include, for example, durability, adaptability to the human body, safety, and the like. Furthermore, since it is introduced by surgery, it must be easy to anastomosis.

  Various types of conventional artificial blood vessels have been developed. For example, in JP2013-031595A (Patent Document 1), a non-woven fabric layer of ultrafine fibers having a diameter of 10 μm or less formed by an electrospinning method is the innermost layer, and at least a cover material (braid) is provided outside the outermost layer. There is disclosed a cylindrical body characterized in that the nonwoven fabric layer and the cover material (braid) are fixed, and when this cylindrical body is used as an artificial blood vessel, the nonwoven fabric layer of ultrafine fibers is the most It is disclosed that it is suitable for an artificial blood vessel because it is in an inner layer (the innermost layer side of a conventional artificial blood vessel is a reinforcing material such as a metal net or woven fabric). In addition, in Patent Document 1, in the case of an artificial blood vessel, in a member that does not allow liquid to pass through at all (those that have no space), endothelial cells do not proliferate, and blood leaks if there are large holes, There is a description that although the pores are vacant, it is recommended that the cellular components immediately become entangled and clogged.

JP2013-031595A

  By the way, it is known that the wall of an arteriovenous (blood vessel) in a living body is composed of three layers of membranes. The inner membrane is the innermost layer of the blood vessel, the middle membrane is the intermediate layer, and the outer membrane is the outermost connective tissue layer. In the elastic arteries, the intima is composed of an endothelial cell layer, the subendothelium and an inner elastic membrane (plate), and the media is composed of elastic fibers, smooth muscle cells, collagen fibers and a matrix (proteoglycan). The outer membrane is composed of collagen fibers and elastic fibers, fibroblasts and macrophages, and vascular and vascular nerves.

Atherosclerotic lesions occur in the intima, and macrophages and smooth muscle cells accumulate lipids (especially LDL) in a thick layer of fibrous connective tissue. As the lesion progresses, lipid accumulation increases and the endothelium (endothelial cell layer and The structure and function of the subendothelium and the inner elastic membrane (plate) are lost, and the medial membrane is unthinned, calcified, and necrotic. If it worsens, blood circulation failure and thrombosis develop.
It is ideal to treat the arteriosclerotic lesion by replacing the artery with a bioabsorbable artificial blood vessel and regenerating the blood vessel walls (intima, media and adventitia). There is still no way to achieve it. In this regeneration process, the inner membrane and inner membrane are formed relatively slowly by stem cells in the blood, and in contrast, the outer membrane enters the living body from the outside relatively quickly. We have found that an organization is formed. If this regeneration process does not proceed satisfactorily, the wall tissue of the blood vessel is not regenerated and a portion thereof is calcified, resulting in stenosis (clogging).

  However, Patent Document 1 described above does not disclose that the tubular body is suitable for an artificial blood vessel that satisfies such a regeneration process. As described above, in Patent Document 1, in the case of an artificial blood vessel, a hole is vacant, but it is only described that a cell component should be immediately entangled with the hole and clogged and blocked. . In particular, it does not mention the difference (rate difference etc.) of the cell regeneration process between the inner membrane and the inner membrane and outer membrane, and a good regeneration process proceeds in an artificial blood vessel that does not consider such a difference in the regeneration process. I can't.

  The present invention has been developed in view of the above-described problems of the prior art, and the object of the present invention is to be applied to, for example, an artificial blood vessel so that the inner wall, the inner wall, and the outer wall of the blood vessel wall are excellent. It is intended to provide a medical multilayer tubular body that can be regenerated.

In order to achieve the above object, the medical multilayer tubular body according to the present invention takes the following technical means.
That is, the medical multilayered tubular body according to the present invention is a tubular body used for medical treatment composed of two or more nonwoven fabric layers, and is manufactured from a fiber having a fiber diameter of 20 μm or less manufactured using a bioabsorbable polymer. A hollow cylindrical inner layer composed of a non-woven fabric layer and a bioabsorbable polymer which is provided outside the inner layer and has a difference in bioabsorbability from the bioabsorbable polymer of the inner layer. And a hollow cylindrical outer layer composed of a nonwoven fabric layer made of fibers thicker than the fiber diameter of the fibers.

Preferably, between the inner layer and the outer layer, an intermediate layer in which a bioabsorbable polymer having a higher bioabsorbability than the bioabsorbable polymer of the outer layer is added to the nonwoven fabric layer constituting the outer layer, or the outer layer It can comprise so that the intermediate | middle layer comprised including the bioabsorbable polymer whose bioabsorbability is quicker than a bioabsorbable polymer may be further included.
More preferably, the nonwoven fabric layer constituting the inner layer is composed of a mixture of collagen and a copolymer of lactic acid and caprolactone which are bioabsorbable polymers, and the nonwoven fabric layer constituting the outer layer is a bioabsorbable polymer. It is comprised by the copolymer of lactic acid and caprolactone which are these, The said bioabsorbable difference can be comprised so that it may be expressed by the difference in the copolymerization ratio of lactic acid and caprolactone.

More preferably, the copolymerization ratio of lactic acid and caprolactone in the inner layer is 50:50, and the copolymerization ratio of lactic acid and caprolactone in the outer layer is 75:25.
More preferably, the mixing ratio of the collagen and the copolymer of lactic acid and caprolactone in the inner layer may be 50 wt% to 1 wt%: 50 wt% to 99 wt%.

More preferably, the inner layer may be constituted by a nonwoven fabric layer manufactured by an electrospray deposition (ESD) method, and the outer layer may be constituted by a nonwoven fabric layer manufactured by a melt blow method.
More preferably, the cylindrical body can be configured to be an artificial blood vessel.

  According to the medical multilayered tubular body of the present invention, it can be applied to, for example, an artificial blood vessel, and the inner membrane, middle membrane and outer membrane of the blood vessel wall can be regenerated well.

FIG. 2 is a schematic overall perspective view (A) and a cross-sectional view (B) of an artificial blood vessel that is an example of a medical multilayer tubular body according to the present invention. It is the typical whole perspective view (A) and sectional drawing (B) of the artificial blood vessel which is another example of the medical multilayered tubular body which concerns on this invention. HE (hematoxylin and eosin) -stained drawing-substituting photograph (A) showing normal blood vessels of the abdominal aorta of the dog and drawing-substituting photograph showing the regenerating blood vessels of the abdominal aorta reproduced by the medical multilayered tubular body according to the present invention ( B).

Hereinafter, the medical multilayered tubular body according to the present invention will be described in detail with reference to the drawings. In the following, a medical multi-layered cylindrical body used for an artificial blood vessel will be described as an example of a medical material according to the present invention, but it is also suitable for other in vivo tubular tissues (digestive tract of digestive organs, etc.). ing. Therefore, the medical multilayer tubular body according to the present invention is not limited to those used as artificial blood vessels.
[Constitution]
1A is an overall perspective view of an artificial blood vessel 100 which is an example of a medical multilayer tubular body according to the present embodiment, FIG. 1B is a cross-sectional view thereof, and FIG. An overall perspective view of an artificial blood vessel 200, which is another example of the medical multilayer tubular body according to the embodiment, is shown in FIG. 1 and 2 are schematic diagrams for explaining the structure. The cross section of the artificial blood vessel 100 in FIG. 1 is a perfect circle, and the ratio between the length and the tube diameter is the inner layer and The ratio of the thickness of the outer layer is also schematic and virtual, and the cross section of the artificial blood vessel 200 in FIG. 2 is a perfect circle, and the ratio of the length to the tube diameter is the thickness of the inner layer, the intermediate layer, and the outer layer. These ratios are also shown as schematic and virtual ones.

  Referring to FIG. 1, an artificial blood vessel 100, which is an example of a medical multilayer tubular body, is a tubular body made of two nonwoven fabric layers and used for regenerative medicine, and is manufactured using a bioabsorbable polymer. There is a difference in bioabsorbability between the hollow cylindrical inner layer 110 made of a nonwoven fabric layer made of fibers having a fiber diameter of 20 μm or less, and the bioabsorbable polymer of the inner layer 110 provided on the outer side of the inner layer 110 (decomposition and absorption). And a hollow cylindrical outer layer 120 made of a non-woven fabric layer made of a fiber that is manufactured using a bioabsorbable polymer (with different speeds) and that is thicker than the fiber diameter of the fibers of the inner layer 110.

  As shown in FIG. 2, an artificial blood vessel 200, which is another example of a medical multi-layer cylindrical body, includes an outer layer between an inner layer 110 and an outer layer 120 in addition to the configuration of the artificial blood vessel 100 shown in FIG. It further includes an intermediate layer obtained by adding a collagen component to the nonwoven fabric layer constituting 120. The intermediate layer 220 may be an intermediate layer including a collagen component (not including a nonwoven fabric) (for example, collagen is held via a non-limiting medium). Here, the collagen contained in the intermediate layer 220 is an example of a bioabsorbable polymer, and if it is a bioabsorbable polymer having a faster bioabsorbability than the bioabsorbable polymer constituting the outer layer 120, It is not limited to collagen.

  The nonwoven fabric fibers constituting the inner layer 110 have a fiber diameter of 0.1 μm to 20 μm, particularly preferably 0.5 μm to 15 μm, and more preferably 10 μm or less. The nonwoven fabric fibers constituting the outer layer 120 are: The fiber diameter is 0.5 μm to 30 μm, preferably 0.7 μm to 20 μm. The nonwoven fabric constituting the inner layer 110 has a thickness of 3 μm to 3000 μm, and preferably 10 μm to 2000 μm, and the nonwoven fabric constituting the outer layer 120 has a thickness of 3 μm to 5000 μm, particularly 10 μm. It is preferably ˜2500 μm.

In addition, the diameter of the medical multilayered tubular body according to the present invention taking these artificial blood vessel 100 and artificial blood vessel 200 as an example appropriately corresponds to the thickness of the blood vessel to be applied.
Further, the composition of the inner layer 110, the outer layer 120, and the intermediate layer 220 will be described. The nonwoven fabric layer constituting the inner layer 110 is composed of a mixture of collagen and a copolymer of lactic acid and caprolactone, which are bioabsorbable polymers (copolymerization ratio of lactic acid and caprolactone is 50:50). The nonwoven fabric layer constituting the outer layer 120 and the intermediate layer 220 (when the intermediate layer has a structure in which a collagen component is added to the nonwoven fabric layer) is a copolymer of lactic acid and caprolactone (copolymerization ratio of lactic acid and caprolactone) that is a bioabsorbable polymer Is composed of 75:25). Thus, the inner layer 110, the outer layer 120, and the intermediate layer 220 have different copolymerization ratios of lactic acid and caprolactone. Regarding the copolymerization ratio of lactic acid and caprolactone, it is known that the larger the proportion of lactic acid, the slower the bioabsorbability (biodegradability), and the larger the proportion of caprolactone, the faster the bioabsorbability (biodegradability). Therefore, in the artificial blood vessel 100, the inner layer 110 is absorbed (decomposed) faster by the living body than the outer layer 120, and in the artificial blood vessel 200, the inner layer 110 is absorbed faster by the living body than the outer layer 120 and the intermediate layer 220. (Disassembled).

  Here, the nonwoven fabric layers constituting the inner layer 110 and the outer layer 120 (and also the intermediate layer 220) do not necessarily need to use bioabsorbable polymers having different compositions (particularly, the copolymerization ratio of lactic acid and caprolactone). It is important that the bioabsorbability is different, and it is conceivable to use bioabsorbable polymers having different compositions as one method for realizing this. For example, even if it is a nonwoven fabric which consists of the same polymer composition, it is possible to change bioabsorbability by changing the fiber diameter of the fiber which comprises a nonwoven fabric, and / or the thickness of a nonwoven fabric.

  The mixing ratio of the collagen and the copolymer of lactic acid and caprolactone in the inner layer 110 is 50% by weight to 1% by weight: 50% by weight to 99% by weight, particularly 25% by weight: 75% by weight. preferable. Here, in the nonwoven fabric layer constituting the inner layer 110, even a material that is enzymatically hydrolyzed in vivo (collagen described above as an example), a material that is hydrolyzed nonenzymatically (such as lactic acid and A copolymer of caprolactone). That is, the collagen of the inner layer 110 may be a material that is hydrolyzed non-enzymatically. Thus, the nonwoven fabric layer constituting the inner layer 110 does not contain collagen (copolymer of lactic acid and caprolactone). Only).

  The bioabsorbable polymer constituting the artificial blood vessel 100 and the artificial blood vessel 200 is not limited to the above-described polymer. 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, Synthetic absorbent polymers such as L, DL form) -ε-caprolactone copolymer. These may be used independently and 2 or more types may be used together. Among these, polyglycolic acid, lactide (D, L, DL) -ε-caprolactone copolymer, glycolic acid-ε-caprolactone copolymer and glycolic acid-lactide (D, L, DL form) -ε-caprolactone copolymer is preferred, and as described above, in this embodiment, the copolymerization ratio is 75:25 or 50:50. A copolymer of lactic acid (lactide) and caprolactone is used.

Thus, these artificial blood vessel 100 or artificial blood vessel 200 is
(1) Due to the difference in copolymerization ratio of the copolymer of lactic acid and caprolactone, the outer layer 120 (and the intermediate layer 220) is absorbed by the living body later than the inner layer 110,
(2) Because the inner layer 110 has a smaller fiber diameter than the outer layer 120 (and the intermediate layer 220) due to the difference in the fiber diameter of the fibers constituting the nonwoven fabric (the inner layer 110 has a nano-class fiber diameter), the inner layer 110 is the outer layer 120. (And the middle layer 220) is finer than the nonwoven fabric,
(3) The inner layer 110 contains collagen in addition to a copolymer of lactic acid and caprolactone,
(4) When the intermediate layer 220 is provided, the intermediate layer 220 is an intermediate layer (nonwoven fabric + collagen) obtained by adding a collagen component to the non-woven fabric layer constituting the outer layer 120, or an intermediate layer configured to include a collagen component. Layer (collagen retained through non-limiting medium),
It has the structural features.

A method for manufacturing the artificial blood vessel 100 and the artificial blood vessel 200 having the above structural features will be described.
[Production method]
The inner layer 110 in the artificial blood vessel 100 and the artificial blood vessel 200 is composed of a nonwoven fabric layer manufactured by an electrospray deposition (ESD) method, and the outer layer 120 and the intermediate layer 220 are composed of a nonwoven fabric layer manufactured by a melt blow method. Yes. Since the electrospray deposition (ESD) method is known to be a method manufactured using, for example, an ELSP apparatus disclosed in Japanese Patent No. 396360, the electrospray deposition (ESD) method itself The detailed description of will not be repeated here. Furthermore, since the melt-blowing method is known to be a method manufactured using, for example, the technique disclosed in Japanese Patent No. 3364367, detailed description of the melt-blowing method itself will not be repeated here.

  In addition, the collagen dipping method of the intermediate layer 220 is performed by a reaction in which a non-woven fabric produced by a melt blow method is immersed in a solution of collagen and glycerin and crosslinked at 110 ° C. Further, the intermediate layer 220 may be an intermediate layer that does not include a non-woven fabric and includes a collagen component. In this case, if the collagen is held in a non-limiting medium (layered material). Well, not particularly limited.

Furthermore, about the manufacturing method which makes a shape a cylindrical body, for example, as shown in FIG.
<First Step> Collagen and bioabsorbable polymer having a copolymerization ratio of lactic acid and caprolactone of 50:50 on an electrode of a stainless steel round bar using an electrospray deposition method at 25 wt%: 75 wt% , Jetting from each syringe to produce a hollow cylindrical nonwoven fabric of the inner layer 110,
<Second step> Using a melt blow method on the upper layer, a bioabsorbable polymer having a copolymerization ratio of lactic acid and caprolactone of 75:25 is laminated to produce a hollow cylindrical nonwoven fabric of the intermediate layer 220,
<Third step> In this state, the intermediate layer 220 is immersed in a solution of collagen and glycerin and subjected to a crosslinking reaction at 110 ° C.
<Fourth step> Further, by using a melt blow method on the upper layer, a bioabsorbable polymer having a copolymerization ratio of lactic acid and caprolactone of 75:25 is laminated to produce a hollow cylindrical nonwoven fabric of the outer layer 120. A blood vessel 200 is manufactured.

In the method for manufacturing the artificial blood vessel 100, the above-mentioned <second step> and <third step> are not necessary. Further, in the method of manufacturing the artificial blood vessel 200, when the intermediate layer 220 is an intermediate layer that does not include a nonwoven fabric and includes a collagen component, as described above, a layered product that holds collagen as the intermediate layer 220 May be formed.
A method of using the artificial blood vessel 100 and the artificial blood vessel 200 according to the present embodiment manufactured by the above manufacturing method and having a characteristic configuration will be described below.
[how to use]
For example, a surgical operation is performed to replace an artery that has developed an arteriosclerotic lesion with the artificial blood vessel 100 or the artificial blood vessel 200 to regenerate the blood vessel walls (intima, media, and outer membrane).

These artificial blood vessel 100 and artificial blood vessel 200 are, as described above,
(1) Due to the difference in copolymerization ratio of the copolymer of lactic acid and caprolactone, the outer layer 120 (and the intermediate layer 220) is absorbed by the living body later than the inner layer 110,
(2) Because the inner layer 110 has a smaller fiber diameter than the outer layer 120 (and the intermediate layer 220) due to the difference in the fiber diameter of the fibers constituting the nonwoven fabric (the inner layer 110 has a nano-class fiber diameter), the inner layer 110 is the outer layer 120. (And the middle layer 220) is finer than the nonwoven fabric,
(3) The inner layer 110 contains collagen in addition to a copolymer of lactic acid and caprolactone,
(4) When the intermediate layer 220 is provided, the intermediate layer 220 is an intermediate layer (nonwoven fabric + collagen) obtained by adding a collagen component to the non-woven fabric layer constituting the outer layer 120, or an intermediate layer configured to include a collagen component. Layer,
It has the structural features.

For this reason, until several months have passed since surgery, the structural features (1) to (4) described above
(A) Since the outer layer 120 (and the intermediate layer 220) is rough, cells rapidly invade and tissue regeneration takes place quickly.
(B) The outer layer 120 (and the intermediate layer 220) is slow in bioabsorption (slow dissolution) while maintaining the outer shape of the artificial blood vessel, and the eyes are rough, so cells from the body (other than blood in the blood vessel) can reach all layers. Suitable for the outer membrane which is easy to enter quickly and is regenerated faster than the inner membrane and inner membrane,
(C) Since the inner layer 110 has fine eyes and is difficult for cells in the blood to infiltrate, the cells gradually infiltrate from the lumen side to the outside as the bioabsorbable polymer constituting the inner layer 110 is decomposed and absorbed. , Tissue regeneration takes place slowly,
(D) The inner layer 110 does not need to maintain the outer shape of the artificial blood vessel, and may absorb rapidly (even if it dissolves quickly), and has a fine eye so that cells in the blood slowly infiltrate and regenerate. And suitable for the inner membrane,
(E) Since the inner layer contains collagen, it is suitable for cell regeneration of the blood vessel wall.
The effect is expressed.

  When the medical multilayered tubular body according to the present invention is applied to an artificial blood vessel, the inner membrane, the middle membrane and the outer membrane of the blood vessel wall can be regenerated well. A cross-sectional view of the blood vessel thus regenerated is shown in FIG. FIG. 3 is a drawing-substituting photograph showing the tissue evaluation of the dog abdominal aorta stained with HE (hematoxylin and eosin), and FIG. 3 (A) shows normal blood vessels (normal in the sense that they are not regenerated blood vessels). FIG. 3B is a drawing-substituting photograph showing a regenerated blood vessel regenerated by the artificial blood vessel 100 (or the artificial blood vessel 200) which is a medical multilayer tubular body according to the present invention. From these figures, it can be recognized that even the regenerated blood vessel shown in FIG. 3 (B) forms the same tissue as the normal blood vessel shown in FIG. 3 (A). That is, as shown in FIG. 3B, the inner wall, the inner wall, and the outer wall of the blood vessel wall are regenerated well in the regenerated blood vessel, there is no stenosis (clogging), no rupture, and calcification It can be seen that the vascular tissue is regenerated well.

As described above, according to the artificial blood vessel according to the present embodiment which is an example of the medical multilayer tubular body according to the present invention, the structural features of (1) to (4) described above are provided. Since the above-described operational effects (A) to (E) are expressed, when the medical multilayered tubular body according to the present invention is applied to an artificial blood vessel, the intima, media and adventitia of the blood vessel wall are regenerated well. can do.
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  INDUSTRIAL APPLICABILITY The present invention is suitable for medical materials applied to in vivo tubular tissues (blood vessels, digestive tracts, etc.), and when applied to an artificial blood vessel, the inner wall, media and outer membranes of the blood vessel wall are good. It is particularly preferable in that it can be regenerated.

100, 200 Artificial blood vessel (multi-layer medical cylindrical body)
110 Inner layer 120 Outer layer 220 Middle layer

Claims (7)

A cylindrical body composed of two or more nonwoven layers and used for medical treatment,
A hollow cylindrical inner layer made of a non-woven fabric layer made of a bioabsorbable polymer and having a fiber diameter of 20 μm or less;
Constructed from a non-woven fabric layer that is provided on the outer side of the inner layer and is made of a bioabsorbable polymer that is different in bioabsorbability from the bioabsorbable polymer of the inner layer and is made of fibers thicker than the fiber diameter of the fibers of the inner layer A hollow cylindrical outer layer,
A medical multi-layered cylindrical body.   Between the inner layer and the outer layer, an intermediate layer in which a bioabsorbable polymer having a higher bioabsorbability than the bioabsorbable polymer of the outer layer is added to the nonwoven fabric layer constituting the outer layer, or the bioabsorbability of the outer layer The medical multilayer tubular body according to claim 1, further comprising an intermediate layer comprising a bioabsorbable polymer having a higher bioabsorbability than the polymer. The nonwoven fabric layer constituting the inner layer is composed of a mixture of collagen and a copolymer of lactic acid and caprolactone which are bioabsorbable polymers,
The nonwoven fabric layer constituting the outer layer is composed of a copolymer of lactic acid and caprolactone which are bioabsorbable polymers,
The medical multilayer tubular body according to claim 1 or 2, wherein the difference in bioabsorbability is expressed by a difference in copolymerization ratio between lactic acid and caprolactone. The copolymerization ratio of lactic acid and caprolactone in the inner layer is 50:50,
The multilayered tubular body for medical use according to claim 3, wherein a copolymerization ratio of lactic acid and caprolactone in the outer layer is 75:25.   The multi-layered cylindrical shape for medical use according to claim 3 or 4, wherein a mixing ratio of collagen and a copolymer of lactic acid and caprolactone in the inner layer is 50% by weight to 1% by weight: 50% by weight to 99% by weight. body. The inner layer is composed of a nonwoven fabric layer manufactured by an electrospray deposition (ESD) method,
The said outer layer is a medical multilayer cylindrical body in any one of Claims 1-5 comprised with the nonwoven fabric layer manufactured by the meltblowing method.   The medical multilayer tubular body according to any one of claims 1 to 6, wherein the tubular body is an artificial blood vessel.