JPH11335A - Blood vessel anastomosis aid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a blood vessel anastomosis aid which, in an operation whereby a blood vessel is bypassed by another blood vessel, allows the blood vessels to be anastomosed easily and properly while securing blood flow remaining in the centers and peripheries of the blood vessels. SOLUTION: This anastomosis aid comprises a flexible hollow conduit 2 having open ends 4a, 4b, with at least two annular projections 6 provided on the outer surface of the conduit 2 and with a takeout means provided for taking out the conduit 2 from within a blood vessel. The conduit 2 has a higher elastic value than the blood vessel and has a self-restoration property such that the lumen of the conduit 2 after it is restored remains the same as before the hollow conduit 2 is curved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vascular anastomosis assisting device for use in coronary artery bypass surgery for treating coronary artery disease.

[0002]

2. Description of the Related Art Coronary artery disease such as angina pectoris and myocardial infarction is the most frequent disease among heart diseases encountered in outpatient and emergency medical care. In these coronary artery diseases, the most frequently performed operation is coronary artery bypass surgery. Coronary artery bypass surgery involves bypassing the peripheral portion of the coronary stenosis from the ascending aorta using a piece of autologous saphenous vein (so-called AC bypass surgery), or connecting an arterial graft such as the internal thoracic artery to the coronary artery. There is a method of direct anastomosis, and in particular, the latter artery graft method is often applied because of its excellent patency rate. Conventionally, when performing coronary artery bypass surgery, in order to secure blood flow to the peripheral side of the coronary arteries, conventionally, blood is flowed from the femoral artery using an external shunt, or a myocardial protection method (injecting myocardial protective fluid into the coronary artery) And percutaneous cardiopulmonary support (PCPS: short-term extracorporeal circulation) to percutaneously insert and withdraw blood vessels. , Forming a static-arterial bypass).

[0003] Recently, as a minimally invasive cardiac surgery, a minimally invasive coronary artery bypass surgery (MIDCAB) that does not perform extracorporeal circulation with a small surgical wound has also been performed. This method has the advantage of avoiding blood damage due to extracorporeal circulation and reducing the chance of infection, but on the other hand, blood flow to the peripheral side of the coronary artery is blocked during vascular anastomosis, so blood flow from the proximal side of the coronary artery However, there is a risk that the patient may die due to myocardial infarction due to acute occlusion. In particular, this is a problem when anastomosis is troublesome and a blood vessel is blocked for a long time. As described above, MI
In the case of coronary artery bypass grafting by DCAB, blood is blocked during vascular anastomosis, so the blood flow in the coronary artery is slight (that is, coronary artery stenosis is about 75 to 90%).
Therefore, there is a concern about the effect, and it is desired that a blood flow can be secured from the central side of the coronary artery to the peripheral side during the arterial graft operation. But now, during arterial grafts,
There is no suitable thing to use to ensure coronary blood flow. That is, there is known a simple vascular anastomosis assisting device or device which secures the blood flow between the central side and the peripheral side of the coronary artery during the vascular anastomosis between the internal thoracic artery and the coronary artery and can be removed when the anastomosis is completed. Not.

[0004]

Accordingly, an object of the present invention is to provide a blood vessel bypass operation (for convenience, the bypassed blood vessel is called a bypassed blood vessel, and the bypassed blood vessel is called a bypass blood vessel). The anastomosis between the bypassed blood vessel and the bypassed blood vessel can be easily and appropriately performed while ensuring the blood flow remaining between the central side and the peripheral side of the bypassed blood vessel (damage to the intima of the blood vessel or obstruction during the anastomosis). And to provide a blood vessel anastomosis assisting device that does not interfere after the blood vessel anastomosis. In particular, it is an object of the present invention to provide a vascular anastomosis assisting device which can be used for anastomosis between a coronary artery and an internal thoracic artery in a cardiovascular bypass operation.

[0005]

Means for Solving the Problems The present inventor has solved the above-mentioned problems with a blood vessel anastomosis assisting device comprising a hollow conduit having specific physical properties and shape. That is, the present invention is a flexible hollow conduit having open ends at both ends, provided with at least two annular projections on an outer surface of the conduit, and withdrawing means for removing the conduit from inside a blood vessel. The hollow conduit has a higher elasticity and a self-restoring property than the blood vessel, and the lumen of the conduit after the restoration is secured as before the hollow conduit is bent. Further, the second embodiment of the present invention is a vascular anastomosis assisting tool having the above-described vascular anastomosis assisting tool and a rod-shaped guide which can pass through the hollow lumen of the assisting tool. The guide is flexible so that it can be easily inserted into a blood vessel, but has a higher elasticity than the blood vessel to be inserted, and further has an inner diameter of the hollow conduit so that the hollow conduit can be guided along the guide into the blood vessel. Has an outer diameter of 50 to 90% and an axial length of at least three times that of the hollow conduit.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION
The dimensions will be briefly described with examples. This vascular anastomosis assisting device is mainly used to form an end-to-side anastomosis of a blood vessel (a hole is formed in a side of a certain blood vessel, and the ends of other blood vessels are joined and sewn along the hole to connect the blood vessels to each other. And anastomosis at the side). Then, the practitioner performs the operation with the anastomosis assisting tool while securing the blood flow of one blood vessel and holding (with the blood vessel anastomosis assisting instrument) the suture portion of the blood vessel to be newly anastomosed. When applying the vascular anastomosis assisting device of the present invention to a coronary artery, the preferred one is 0.6 to 1.3.
1 is a hollow conduit having an inner diameter of 1.25 mm and an outer diameter of 1.25 to 1.75 mm. If the outer diameter of the hollow conduit is too large, it is difficult to insert into a small blood vessel, and if the inner diameter of the hollow conduit is too small, it is difficult to obtain a sufficient blood flow. Sufficient blood flow is 20
A blood flow of 5 to 20 ml / min or more can be obtained under a pressure of ６０60 cm water column. As described above, as a blood vessel anastomosis assisting device, a hollow conduit having a large inner diameter and a small outer diameter is desirable, and therefore, the thickness of the conduit is required to be as thin as possible.

On the other hand, if the thickness of the hollow conduit is too thin, the physical properties and strength required for the conduit are reduced, and the hollow conduit cannot be used as a blood vessel anastomosis assisting device. Therefore, the preferred inner diameter / outer diameter ratio of the blood vessel anastomosis assisting device of the present invention is 0.5 to 0.8. Since the strength and physical properties of the hollow conduit are affected by the material itself, the preferred range of the thickness of the conduit cannot be unconditionally determined. However, general-purpose synthetic materials, such as polyurethane and polyamide, which are generally inserted into blood vessels, do not have sufficient thickness. It is desirable that the thickness is 0.05 mm or more. This is not to prevent the conduit from being damaged, but rather from the viewpoint of the shape retention ability of the hollow conduit at the time of vascular anastomosis, self-restoration, etc.
The above-mentioned synthetic resin requires a predetermined thickness. The shape retention capability means that the blood vessel must be tightened together with the hollow conduit with a suture (tourniquet) in order to hold the hollow conduit in place during blood vessel anastomosis and to prevent blood from flowing outside the conduit, At that time, it refers to the capacity that can be secured without blocking the lumen of the hollow conduit. Therefore, it is necessary to have at least higher elasticity than blood vessels. Further, it is preferable that the open end of the hollow conduit has a shape that does not hinder the smooth flow of the liquid in the lumen of the conduit.
For example, a smoother blood flow can be obtained by forming the cut end of the open end obliquely and increasing the open end area (the area of the open end lumen).

[0008] The shape of the end of the vascular anastomosis aid including the open end is one of the important points of the present invention. First, the first
In addition, the shape of the open end must be considered from the viewpoint of preventing damage to living tissue. That is, it is required that the shape be such that the intima of the blood vessel is not damaged when the hollow conduit is inserted and held in the blood vessel or when the conduit is removed from the blood vessel. For example, it is also effective to make the cut angle of the open end (the angle formed by the plane parallel to the open end with the conduit axis). The cut angle α is 4
It is preferable that 5 ° <α <80 °. If the angle is too sharp, there is a risk of damage to the intima. Conversely, if the angle is too obtuse, it becomes difficult to insert into the blood vessel, and the open end area becomes small. It is also possible to adopt a rounded shape such as chamfering the edge of the opening end.

Second, the shape of the open end of the blood vessel anastomosis assisting device must be examined from the viewpoint of easy insertion into the blood vessel. For example, to facilitate insertion of the anastomosis assisting tool into a blood vessel, a beak-shaped insertion protrusion may be formed at at least one open end of the hollow conduit. If a thin insertion protrusion is formed at the end of the hollow conduit, the conduit can be easily inserted into the blood vessel by inserting the narrow protrusion into a small incision formed in the blood vessel.
The preferred shape and dimensions of the insertion protrusion are specifically described below. As the shape of the insertion protruding portion, there is a shape that gradually becomes thinner toward the tip portion, or a shape in which the tip portion and the root end portion (portion connected to the opening end) have substantially the same width. The former is desirable in terms of ease. Those having a maximum width of the insertion protrusion in the range of 1/10 to 1/3 of the outer diameter of the conduit are gripping (operability when gripping the insertion protrusion with tweezers), insertion, and guidance. (The ability of the projection to guide the hollow conduit body into the blood vessel). When the length of the insertion protrusion is in the range of 3 to 12 mm, the protrusion can be easily inserted into the blood vessel without obstruction.

The above-mentioned insertion protrusion may be formed at both open ends of the hollow conduit. However, when this protrusion is formed only at one end and the other end is inserted by a rod-shaped guide. , The operation becomes easier. That is, a rod-shaped guide longer than the conduit was passed through the lumen of the hollow conduit, and the distal end of the guide was protruded from one end where the insertion protrusion was not provided (the side on which the protrusion was not formed). Insert into the small incision. Therefore, it is desirable that the tip of the guide is processed so as not to damage the living tissue. For example, processing such as forming a contact portion with a living tissue so as to have a gentle curve, chamfering the shape of the guide tip (shaving a sharp edge and rounding), or the like is performed.
Further, although the shape is not characteristic, the tip portion can be made lubricious. The outer diameter of the guide is preferably 50 to 90% of the inner diameter of the hollow conduit. If it is too large, it is difficult to slide along the guide, and if it is too small, it is useless as a guide. The overall length of the guide must be at least three times the axial length of the hollow conduit, since the guide must be removed after guiding the hollow conduit into the blood vessel and inserting the conduit into the blood vessel. The one having an axial length of about 10 times is preferable. For example, a guide length of about 150 mm is easy to use for coronary artery bypass surgery. In addition, since the guide must be inserted into the blood vessel prior to the anastomosis assisting device and guide the anastomosis assisting device, it is useless unless it is elastic and has a waist than the blood vessel. Considering pod damage and the like, appropriate flexibility is also required.

Further, the blood vessel anastomosis assisting device must surely hold the blood vessel so as not to move from a predetermined position during the anastomosis of the blood vessel, and must take out the hollow conduit implanted in the blood vessel immediately before the end of the operation. Therefore, the vascular anastomosis assisting device must be shaped to meet these purposes. First, a structure required for holding the blood vessel anastomosis assisting device at a predetermined position in the blood vessel and flowing blood only to the hollow conduit lumen will be described. Two annular protrusions are provided on the outer surface near the open end of the hollow conduit for two purposes. The first is to hold the conduit in a predetermined position in the blood vessel, and the second is to clamp the blood vessel together with the hollow conduit with a tourniquet or the like so that blood flows only through the lumen of the hollow conduit. For the above purpose, the annular projection may have a shape, a height, and a width that allow the suture to be locked to the projection when the anastomosis assisting device is held in the blood vessel.

Next, the means for taking out the hollow conduit from the blood vessel will be described. In order to remove the hollow conduit after the anastomosis is completed, the vascular anastomosis assisting device needs to be provided with a removal means. This removing means can also serve as a position adjusting means for changing or adjusting the position in the blood vessel when the hollow conduit is inserted into the blood vessel. For example, if a string-shaped take-out means (hereinafter, referred to as a string for simplicity) is provided on the central portion or the outer surface of the hollow conduit, the position of the hollow conduit can be easily adjusted at the time of insertion into a blood vessel or after insertion. In addition, the hollow conduit can be easily removed from the blood vessel immediately before the end of the vascular anastomosis. The string does not cut when it is pulled, and it is sufficient if the position of the hollow conduit can be adjusted and it can be easily removed from the inside of the blood vessel, and the material, shape, and dimensions other than the outer diameter are not particularly limited. . Since the string extends outside the blood vessel from the incision hole in the blood vessel, it is preferable that the outer diameter be as small as possible. Preferred are thin but hard-to-cut sutures (either natural or synthetic resin), fishing tackles, etc.
The length is 5-10 cm. The connection of the string to the hollow conduit is not particularly limited, such as adhesion, welding, physical connection (tie), and the like. The formation position of the extraction means is not particularly limited, but if it is formed at a central portion on the outer surface of the hollow conduit, particularly at a position substantially equal from both open ends, it is easy to take out the vascular anastomosis assisting tool from the unsewn portion of the blood vessel. is there.

Next, physical characteristics required for the blood vessel anastomosis assisting device and materials for realizing the physical characteristics will be described. Hollow conduits can be inserted into the blood vessel without damaging the intima of the blood vessel, have the shape-retaining ability during insertion, and have to be restored to their original shape after insertion, so that the conduit must first be moderately flexible And elasticity are required. However, it is difficult to insert the hollow conduit into the blood vessel only by being flexible, and it cannot be self-recovered in the blood vessel. Also, to block blood flow outside the hollow conduit when inserted into the blood vessel,
The hollow conduit must be tightened together with a suture (tourniquet) from outside the blood vessel. However, if the hollow conduit is as soft (low elasticity) as the blood vessel, the hollow conduit will be closed when tightened. Resulting in. Therefore, the hollow conduit must at a minimum have a higher elasticity than the blood vessels. Then, the lumen of the conduit can be secured even by tightening of external force, and a sufficient blood flow can be maintained.

Further, when the vascular anastomosis assisting device releases the external force after bending the hollow conduit by an external force, the hollow conduit can return to its original shape by itself (this is referred to as self-restoring property in this specification). ) Has characteristics. Then, even after the hollow conduit is restored to its original shape, the lumen of the hollow conduit is not narrowed, and the hollow conduit is secured as before the bending (of the hollow conduit). Here, the same lumen is not strictly meaning that the lumen of the hollow conduit is maintained at 100%, but the flow rate of the liquid flowing through the hollow conduit is substantially the same before bending and after restoring. It means that Suitable materials for making such hollow conduits include polyurethane, ethylene-vinyl acetate copolymer (EVA), polyamide, and the like. Among them, polyurethane is preferred from the viewpoint of safety, processability, use results in living bodies, and the like.
~ 80 are preferred. As a material for the guide, polyurethane, polyamide, Kevlar and the like are also preferable.

Next, a description will be given of features other than the shape and the mechanical characteristics, which are provided in the blood vessel anastomosis assisting device and make the operation very convenient. To facilitate insertion and removal of the vascular anastomosis aid into and out of the blood vessel or to prevent intimal damage to the blood vessel, not only change the shape of the open end, but also lubricate part of the outer surface of the hollow conduit. Is also effective. For example, near the open end, that is, from the open end to the nearby annular protrusion,
The outer surface of the conduit is graft-polymerized with a hydrophilic polymer such as acrylic acid or polyacrylamide by plasma pretreatment, corona treatment, ozone treatment or the like. Thereby, semi-permanent lubricity can be imparted to the hollow conduit. In order to obtain lubricity more easily, biocompatible jelly or the like may be applied near the open end of the conduit. In addition, there is a problem of antithrombotic property that is indispensable in a vascular anastomosis assisting device. The antithrombotic treatment of the surface of the hollow conduit not only ensures blood flow during the operation, but also has an effect in terms of postoperative anastomotic patency. Therefore, it is preferable to perform an antithrombotic treatment on the outer surface of the hollow conduit. For example, heparin may be ion-bonded to the surface of the hollow conduit using a cationic surfactant such as benzalkonium chloride, or a fibrinolytic substance such as urokinase may be bonded.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the vascular anastomosis assisting device of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 to 3, the vascular anastomosis assisting device 1 of the present embodiment mainly includes a hollow conduit 2 and a rod-shaped guide 3. The hollow conduit 2 has an inner diameter of 1.0 mm and an outer diameter of 1.
It is 5 mm long and 20 mm long in the axial direction, and is made of polyether polyurethane. The hollow conduit 2 is produced by a dipping method in which a step of dipping in a polyurethane solution, pulling up and drying is repeated. Open ends 4 having a cut angle of 45 ° are formed at both ends of the hollow conduit 2, and annular protrusions having a width of 1.0 mm and a height of 0.2 mm are provided near the open ends 4 (at positions 1 to 2 mm from the open ends). 5 are formed. And
A beak-shaped insertion protrusion 6 is formed at one open end 4b. The insertion projection 6 has a width d of 0.38 mm and a length of 10 mm, and the projection tip 7 is rounded so as not to damage the intima of the blood vessel, and the projection root end 8 is connected to the bottom of the open end. I have. The insertion protrusion 6 is made by cutting out the end of the hollow conduit, and is dipped so that the cut end (edge) is rounded after cutting out.

A string 9 of polypropylene 1-0 suture is connected at an equal position from both open ends 4a, 4b, that is, just in the middle of the hollow conduit, and the connecting portion 10 is dipped with a polyurethane solution. , Reinforced. Polydimethylacrylamide (PDMAA) is graft-polymerized to the outer surface about 5 mm central from both open ends of the hollow conduit by plasma pretreatment, and has lubricity. After immersing the entire outer surface of the vascular anastomosis aid in a 10% aqueous benzalnium chloride solution,
The antithrombotic treatment is performed by immersing in a 30% heparin aqueous solution. The material used to make the hollow conduit 2 is a polyether segmented polyurethane having a degree of polymerization of 2500. The physical properties of this polyurethane are
Hardness A by the measurement method defined in S (K7311) is 8
0, 100% modulus is 5 N / cm2, 3
00% modulus has 10N / cm2 and rebound resilience is 6
0%.

As shown in FIG. 3, the guide 3 of this embodiment is a rod made of polyamide having a length of 150 mm and an outer diameter of 0.9 mm, which can pass through the lumen of the hollow conduit 2. Used in sets. The distal end portion 11 of the guide is formed in a gentle curved shape, and the guide distal end portion 11a extends from the opening end (center side) 4a on the side where the insertion protrusion 6 is not formed.
Is used in a protruding state. The same lubricity treatment as that of the hollow conduit 2 is applied from the tip of the guide 3 to the center side 75 mm. Further, the entire outer surface of the guide 3 is subjected to the same antithrombotic treatment as the hollow conduit 2.

Next, a procedure (method) for end-to-side anastomosis of the coronary artery 12 and the internal thoracic artery 13 using the vascular anastomosis assisting device 1 of the present invention will be described. 1. First, a mark 14 is placed on the side of the coronary artery where the end of the internal thoracic artery is to be anastomosed. Upstream side (central side) of the mark 1
A suture (tourniquet) 15 is applied to 2a and the downstream side (peripheral side) 12b (FIG. 4). By lifting the tourniquet 15 upward, the blood flow in the coronary artery 12 is blocked. Next, a small incision hole 16 of 4 to 6 mm is made with a scalpel in the marked coronary artery site [FIG. 5]. 2. While blocking the blood flow, insert the distal end portion 11 of the guide into the small incision hole 16,
Next, the guide tip 11 is advanced [FIG. 6]. The hollow conduit 2 has a guide 3 passed through its lumen, and can slide along the guide 3. The hollow conduit 2 is slid along the guide 3 and through the small incision 16 the central coronary artery 1
The hollow conduit 2 is inserted into 2a. 3. The central side tourniquet 15a is slightly loosened, the open end 4a of the hollow conduit is advanced toward the central side, and when the annular projection 5 has passed the place where the tourniquet 15a is hooked,
Tighten the tourniquet again to block blood flow outside the hollow conduit. Next, the guide 3 is slowly pulled out from the open end (the peripheral open end) of the hollow conduit on the side not inserted into the blood vessel, that is, the open end 4b on the side of the insertion protrusion [FIG. 7]. The insertion protrusion 6 is grasped with tweezers or the like, and the hollow conduit 2 is bent as shown in FIG. 8 so that blood flowing into the lumen of the conduit does not leak out from the peripheral open end 4b. In that state,
The insertion projection 6 is inserted into the distal side of the small incision hole 16, and the distal coronary artery 12b is returned so that the bent hollow conduit 2 is restored.
Insert

4. The protrusion 6 inserted into the small incision 16 is further advanced into the coronary artery, and the entire hollow conduit is implanted in the blood vessel. At this time, the string 9 is kept out of the blood vessel through the small incision hole 16, and the position of the hollow conduit in the blood vessel is adjusted while pulling the string 9. When the tourniquet 15b on the distal side is slightly loosened, the hollow conduit 2 self-restores in the coronary artery and returns to a straight line, and the blood flow is resumed as before. Open end 4b at the distal end of hollow conduit
The peripheral tourniquet 15b is tightened again so that blood flowing out of the small incision hole 16 does not leak [FIG. 9]. 5. Next, the end of the internal thoracic artery 17 is joined to the small incision 16 formed in the side of the coronary artery, and the blood vessels are sutured while the periphery of the end of the internal thoracic artery 17 is fitted around the incision 16 [FIG. 10]. 6. Just before the suturing is completed, that is, in a state where the last one or two needles to be sewn remain, the string 9 is pulled out of the blood vessel to take out the hollow conduit 2 from the unsewn portion 18 of the small incision hole while bending. [FIG. 11]. Since there is bleeding from the unsewn portion 18, the remaining suturing is performed immediately. If necessary, the central blood vessel 12a may be fastened with the tourniquet 15a during this time.

[0021]

【The invention's effect】

1. During the arterial graft operation, the remaining coronary artery blood flow is ensured, so that the operation can be performed without having to worry about the interruption time of the blood flow as in the conventional art. In addition, during anastomosis, blood flow between the proximal side and the peripheral side of the coronary artery is limited to only the lumen of the vascular anastomosis assisting device, so that blood does not leak from the anastomotic portion. 2. At the time of blood vessel anastomosis, the auxiliary tool serves as a support for the blood vessel, and is easily sutured. That is, since the assisting device is inserted into the coronary artery,
The diameter of the artery is kept expanded as compared with the time of non-insertion. Therefore, when suturing the end of the internal thoracic artery to the side of the coronary artery, it is easy to join the two and to make the anastomosis easy. Also,
Also in suturing a blood vessel, an auxiliary tool is present in the lumen of the blood vessel, so that the suturing needle acts as a patch cloth, thereby preventing suturing of the blood vessel with a suturing needle. 3. At the end of the blood vessel anastomosis, the auxiliary tool can be quickly and easily removed, so that there is no obstruction, and there is no fear that the blood vessel is obstructed by the auxiliary tool remaining in the blood vessel. 4. The auxiliary device of the present invention has a low risk of damaging the intima of the blood vessel, particularly at the time of insertion and withdrawal, and furthermore, these operations are easy.

[Brief description of the drawings]

FIG. 1 is a schematic front view showing a hollow conduit of a blood vessel anastomosis assisting device of the present invention.

FIG. 2 is a schematic plan view of the hollow conduit.

FIG. 3 is a schematic front view showing a guide of the blood vessel anastomosis assisting device.

FIG. 4 is a diagram showing a state in which a suture (tourniquet) is hung on a coronary artery.

FIG. 5 is a view showing a state where a coronary artery is tightened to form a small incision hole.

FIG. 6 is a view showing a state where a guide is inserted into a coronary artery.

FIG. 7 shows a vascular anastomosis assisting device half inserted into the coronary artery,
It is a figure showing the state where the guide was taken out.

FIG. 8 is a view showing a state where an insertion protrusion is inserted into a coronary artery.

FIG. 9 is a view showing a state where a hollow conduit is completely implanted in a coronary artery.

FIG. 10 is a view in which the end of the internal thoracic artery is joined to the small incision in FIG. 9;

FIG. 11 is a view showing a state where a hollow conduit is taken out from an unsewn portion of a small incision hole.

[Explanation of symbols]

 1. Vascular anastomosis aid 2. Hollow conduit 3. Guide 4. Open end 4a. Open end (center side) 4b. 4. Open end (peripheral side, insertion protrusion side) Annular projection 6. 6. Projection for insertion 7. Projection tip 8. Protruding root end String 10. Connection part 11. Guide tip 12. Coronary artery 12a. Coronary artery (central side) 12b. 12. Coronary artery (peripheral side) Internal thoracic artery 14. Mark 15. Suture (tourniquet) 15a. Suture (central side) 15b. Suture (peripheral side) 16. Small incision hole 17. Internal thoracic artery end Unsewn part d. Width of insertion protrusion

Claims (15)

[Claims] 1. A flexible hollow conduit having open ends at both ends, provided with at least two annular projections on an outer surface of the conduit, and withdrawal means for removing the conduit from within a blood vessel. Wherein the conduit has a higher elasticity and self-restoring property than a blood vessel, and the lumen of the hollow conduit after restoration is assured before bending of the conduit. 2. The blood vessel anastomosis assisting device according to claim 1, wherein the extracting means also functions as a position adjusting means for adjusting a position of the hollow conduit in the blood vessel. 3. The ratio of the inner diameter to the outer diameter of the hollow conduit is 0.5 to 3.
3. The vascular anastomosis assisting device according to claim 1, wherein the ratio is 0.8. 4. The vascular anastomosis assisting device according to claim 1, wherein at least a part of the outer surface of the hollow conduit is lubricious. 5. The vascular anastomosis assisting device according to claim 1, wherein an antithrombotic treatment is applied to a surface of the hollow conduit. 6. The vascular anastomosis assisting device according to claim 1, wherein the open end is formed in a shape that is less likely to damage a living tissue. 7. The vascular anastomosis assisting device according to claim 1, wherein the extracting means is a string connected to a central portion of the hollow conduit. 8. The vascular anastomosis assisting device according to claim 1, wherein at least one open end is provided with a beak-shaped insertion projecting portion. 9. The vascular anastomosis assisting device according to claim 8, wherein a maximum width of the insertion protrusion is 1/10 to 1/3 of an outer diameter of the conduit. 10. The length of the projection for insertion is 3 to 12 m.
10. The vascular anastomosis assisting device according to claim 8, wherein m is m. 11. The vascular anastomosis assisting device according to claim 8, wherein the insertion protrusion is formed only at one opening end. 12. A rod-shaped guide used together with the hollow conduit according to claim 1, wherein the guide has an outer diameter capable of smoothly passing through the lumen of the hollow conduit and at least three times as large as the hollow conduit. A guide for insertion of a blood vessel having a length in the axial direction, which is flexible but has a higher elasticity value than the blood vessel to be inserted. 13. A vascular anastomosis assisting device comprising the vascular anastomosis assisting device according to claim 1 and the guide according to claim 12. 14. The vascular anastomosis assisting device according to claim 13, wherein at least a part of the surface of the guide is subjected to antithrombotic treatment. 15. At least one end of the guide is machined so as not to damage living tissue, and the machined end is passed through the lumen of the conduit and out of the conduit from the open end where the insertion projection is not formed. The vascular anastomosis assisting device according to claim 13 or 14, wherein the device is protruded.