JP2010005246A - Joint structure of stent main wire and linear component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simple joint structure in which a fold-back end, folded part, or enlarged-diameter part of a linear component has no adverse effects on a balloon or artificial vessel, when the linear component such as a strut, hook for stabilizer, or the like is connected to a stent main wire through a joint pipe. <P>SOLUTION: The joint structure of the stent main wire and the linear component allows the stent main wire 2 and the strut 4 to be connected through the joint pipe 7, and the end 4a of the strut 4 passing through the joint pipe 7 to be folded back, folded, or diameter-enlarged. At least an outside of the fold-back end 11, enlarged-diameter end 12, or folded end 13 is chamfered so as to form a chamfer 11a, 12a, or 13a. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a connection structure between a stent main line and a linear component when connecting a linear component including a strut and a stabilizer hook to the stent main line.

  There are many tubular tissues such as blood vessels, bile ducts, ureters or esophagus in the body, and there is a risk that specific diseases such as stenosis and obstruction may occur. For example, in the case of blood vessels, diseases such as stenosis and occlusion, aneurysms and varicose veins may occur. Various devices have been developed for effective treatment.

  Recently, a metal cylindrical instrument called a stent is often used to treat a stenosis of a blood vessel or an aneurysm. For example, when treating a stenosis, the stent is accommodated in a sheath or catheter (hereinafter referred to as a sheath) and transported to the affected area. After reaching the affected area, the stent is detached from the sheath and expanded by a balloon. The stenosis is enlarged and placed for treatment. When treating an aneurysm, a stent graft with a stent covered with an artificial blood vessel is placed inside the aneurysm, and this stent graft is used to resist blood pressure, thereby preventing pressure from acting on the aneurysm. To do.

  As a stent, there is a mesh stent using a metal cylinder formed in a mesh shape. In addition, as described in Patent Documents 1 and 2, a loop stent using a loop in which a round bar-shaped wire is bent in a zigzag and ends of the wire are joined to form a cylindrical shape as a whole. Is also provided.

  In particular, a stent using a loop stent is individually used in accordance with the situation of the affected area to be placed. That is, a case where the loop stent is used alone, and a case where a plurality of loop stents are arranged in the longitudinal direction in accordance with the curved state of the affected part, and these loop stents are used as a composite stent connected to each other by linear parts called struts. There is.

  In the above-mentioned stent, a stabilizer hook that is used when the stent housed in the sheath is placed in the affected area is attached to the loop stent positioned at the head. Furthermore, any of the loop stents constituting the stent is a linear part used to adjust the position of the stent when the stent is inserted into the sheath or when the stent is placed in the affected area, or when the stent is pulled back to the sheath. Also arranged.

  The loop stent, the stabilizer hook attached to the leading portion, the strut connecting the adjacent loop stent, and the pullback member, which constitute the stent, are each formed of a metal round bar-like wire rod. A connection portion is formed at each of the connection portions of the loop stent and the stabilizer hook, the loop stent and the strut, and the loop stent and the pullback member.

  An example of the structure of the connecting portion for connecting the rod-like wire rods in the stent will be described with reference to Patent Documents 1 and 2. First, the stent main line of the target site in the loop stent and the ends of the strut, the stabilizer hook, and the pullback member are formed flat. After that, these molded parts are overlapped with each other and inserted into a pipe formed into a substantially rectangular shape, and by caulking this pipe, any of struts, stabilizer hooks and pullback members is connected to the main stent line. ing.

  As a result of research by the present applicant, in the structure of the connecting portion described in Patent Documents 1 and 2, the stent acts on the stent when the stent is placed in the affected area and the sheath is pulled out by fixing the stent to the organ. It was found that a force in the tensile direction acts. It has been found that there is a possibility that slippage may occur between the main stent line at the connecting portion and the stabilizer hook, strut, and pullback member due to force in the pulling direction, and these may be detached from the pipe. .

  From the results of the above research, the present applicant has proposed the stent described in Patent Document 3. In this technique, when a linear part including a stent main line, a strut, and a stabilizer hook is joined via a joining pipe, a locking portion is formed on the linear part. For this reason, when the tensile force acts on the stent and the linear part fitted to the joining pipe slips, the engaging part engages with the joining pipe, and the linear part does not come off.

JP 2003-062087 A JP 2004-097382 A WO2008 / 013042 publication

  The inventors of the present invention are further developing the stent. In this process, even the stent described in Patent Document 3 is not yet complete, and it has been found that there are some points to be improved.

  That is, in Patent Document 3, when there is a deformation at a portion where the locking portion formed on the linear part protrudes from the joining pipe, this portion is polished so that the bent portion and the folded end are the outer diameter of the joining pipe. It is preferred that the dimensions be approximately the same. However, it is not easy to polish the bent portion and the folded end until they are substantially equal to the outer diameter of the joining pipe, and there is a problem that the cost required for the operation increases. For this reason, it is desired to develop a joint structure that does not adversely affect the balloon or the artificial blood vessel by a simpler method.

  An object of the present invention is to connect a linear part such as a strut or a stabilizer hook to a main stent line via a joining pipe, and has a simple structure with a folded end, a bent part, An object of the present invention is to provide a connection portion structure in which the enlarged diameter portion does not adversely affect the balloon or the artificial blood vessel.

  In order to solve the above problems, the connection structure between the stent main line and the linear part according to the present invention connects the stent main line and the linear part via the joint pipe, and at the end of the linear part that penetrates the joint pipe. The part is folded, bent, or expanded in diameter, and at least the outside of the folded end, the bent end, or the expanded end is chamfered.

  In the connection structure of the stent main line and the linear component according to the present invention, by chamfering at least the outer side of the folded end, the bent end, and the expanded end of the linear component penetrating the joint pipe, Does not adversely affect balloons or artificial blood vessels. The outer side of the end is the side of the linear part along the main stent line that is separated from the main stent line, and the work of chamfering the outer side is extremely easy.

  Therefore, even when a tensile force is applied to the stent, the connection between the linear parts constituting the stent can be reliably maintained. In addition, when relative movement occurs between the connection portion between the main stent line and the linear part and the balloon or the artificial blood vessel, this movement can be performed smoothly, and the end folded at the time of the movement can be performed. There is no possibility that the portion, the bent end portion, or the enlarged diameter end portion may damage the balloon or the artificial blood vessel.

  Hereinafter, preferred embodiments of the connection structure of the main stent line and the linear part according to the present invention will be described. The stent of the present invention is applied to tubular tissues such as blood vessels, bile ducts, ureters or esophagus in a living body, and when diseases such as stenosis and occlusion occur in these tubular tissues. In particular, in the case of a blood vessel, when an aneurysm or varicose vein occurs, it has a function of being placed in the affected area and reinforcing the tubular tissue in the affected area.

  In the connection structure of the stent main line and the linear part of the present invention, the main part of the stent composed of a metal rod-like wire and the linear part including a strut or a stabilizer hook are connected using a joint pipe. Is. And the edge part which penetrated the joining pipe of the linear component connected to a stent main line is return | folded or bent or diameter-expanded, and the outer side of these edge parts is chamfered.

  Therefore, it does not ask whether the stent is configured as a cylindrical stent or a loop stent, but whether these are using linear materials or not. The following example demonstrates the case where a loop stent is used.

  The loop stent is formed in a cylindrical shape by bending a metal round bar-shaped wire (stent main line) in a zigzag manner and butt welding or inserting the ends into a sleeve. This loop stent is welded or caulked in a state where both ends of the stent main line are in contact with each other, and is relatively non-rotatably connected, so that it does not deform when inserted into the sheath with a reduced diameter, Therefore, it is possible to accurately return to the original shape when the diameter is increased by separating from the sheath.

  The stent is not limited in length or thickness, and is configured with an optimal shape and thickness corresponding to the affected area to be placed. For this reason, the stent may be configured by one loop stent or may be configured by connecting a plurality of loop stents in the longitudinal direction. In either case, a stabilizer hook is connected to the leading side of the stent, and a pullback member is connected to the rear end side. When a plurality of loop stents are connected in the longitudinal direction, the loop stents are connected via struts.

  Therefore, when configuring a stent, one loop stent and a stabilizer hook connected to the loop stent are essential, but other parts including the strut and the pullback member are not essential. That is, the strut is a component required when a plurality of loop stents are connected to form a stent, and is not required when a single loop stent is used to form a stent.

  In addition, the stent is not composed of only a loop stent, a stabilizer hook, a strut, and a pullback member, but includes a plurality of rings and fins that are used when covering an artificial blood vessel in addition to each of the members as necessary. Consists of parts. These parts are each configured as a linear part using a metal wire having a circular cross section.

  That is, in the present invention, a linear part is a part necessary for constituting a stent, which is made of a metal wire, and all parts connected to a loop stent or strut via a joint pipe. It is intended. Accordingly, even parts that are omitted in the following description are included as long as they constitute the stent of the present invention.

  In the present invention, the material of the metal wire constituting the linear part typified by a loop stent or strut is not particularly limited, has moderate elasticity and flexibility, and adversely affects living tissue. Any material made of a metal that has no fear can be used. As such a metal, there are metal wires such as a shape memory alloy made of stainless steel or a Ni—Ti alloy, and these materials can be selectively used.

  As a material for the linear part, it is preferable to use a wire made of austenitic stainless steel having high reliability for biocompatibility, and in particular, an austenitic stainless steel wire having a predetermined diameter is reduced in advance. A wire rod obtained by extending the structure into a fiber shape by cold drawing with a surface area is preferable because it maintains appropriate elasticity and flexibility over a long period of time and has high toughness.

  In the present invention, the shape of the joining pipe is not limited, and any shape can be used as long as the linear member can be inserted through the connecting portion. Moreover, the cross-sectional shape in the connection part of the wire which comprises a linear component is not limited. That is, the cross-sectional shape of the wire at the connecting portion may be any of a circular shape, a flat quadrangular shape, or other shapes, for example, enabling relative rotation at the connecting portion, Or it is preferable to set suitably according to the conditions requested | required of a connection part, such as disabling.

  Therefore, it may be an oval pipe having a flat circular shape. In particular, when it is configured to prevent relative rotation of the linear parts, the connecting parts of these linear parts are formed flat, and the linear parts formed flat are used as the joining pipe. It is preferable to use one having a square cross section so that it can be inserted.

  Further, the length of the joining pipe is not particularly limited, and may be a length that can reliably connect the linear parts. In particular, when the stent is a loop stent, the step of connecting the linear parts to the loop stent is after the loop stent is manufactured. Therefore, since the joining pipe is inserted into the main stent line before welding the end faces of the loop stent, it is a necessary condition that the joining pipe can smoothly pass through the bent portion of the zigzag formed in the loop stent.

  For this reason, the joining pipe may be constituted by a single pipe, but it may be preferable that the joining pipe is constituted by a plurality of unit pipes that are short in length and can be easily passed through a zigzag bent portion. is there. Therefore, in the present invention, the joining pipe is not necessarily limited to one constituted by a single pipe, but includes a construction in which a plurality of unit pipes are continuously arranged.

  Also, the material of the joining pipe is not particularly limited, it does not adversely affect the living body, and when a caulking force is applied, it deforms according to this force and can maintain a sufficient strength over a long period of time. Any material can be used. As a material constituting such a joined pipe, it is preferable to use a pipe made of austenitic stainless steel.

  In the present invention, the end of the linear part that penetrates the joining pipe is folded, bent, and expanded in diameter so that it can be locked to the joining pipe (hereinafter referred to as the folded end, the folded end, The enlarged diameter end portion is generically called “locking portion”). For this reason, when these linear parts are about to be pulled out of the joint pipe by the force acting on the loop stent or strut, which is a linear part, the locking portion is locked to the joint pipe and the connection state is maintained. It is possible.

  The locking part formed on the linear part does not necessarily have to be formed on both linear parts in the joint part, but in the case of a linear part whose end part is inserted into the joint pipe, the end part is joined. It is essential to form the locking portion by penetrating the pipe. That is, at the connecting portion between the loop stent and the strut, it is possible to prevent the strut from being detached from the joining pipe by forming a locking portion at an end portion that penetrates the joining pipe of the strut.

  As described above, the shape and structure of the locking portion formed on the linear part is such that the end of the linear part that penetrates the joining pipe is folded back 180 degrees in the opposite direction to be locked to the end of the joining pipe. Linear parts penetrating the joined pipe, or by bent ends that are bent at substantially right angles and locked to the end of the joined pipe It is possible to configure the end portion by expanding the diameter by pressing the end portion and engaging the end portion of the joining pipe.

  By chamfering at least the outer sides of the folded end portion, the bent end portion, and the enlarged diameter end portion (locking portion) formed as described above, relative movement to other parts occurs with respect to these end portions. It is configured so as not to adversely affect. The shape of the chamfer formed at each end is not particularly limited. The chamfer is formed by rounding the edge of the end into a curved surface, C chamfering forming the end edge at a 45-degree slope, or simply the end. Any of chamfering that makes the edge of the surface obtuse is possible.

  Next, the connection structure between the main stent line and the linear part according to the present embodiment will be described with reference to the drawings. FIG. 1 is a diagram for explaining a connection portion structure. FIG. 2 is a diagram for explaining an example of the relationship between a stent and a sheath formed by connecting a plurality of loop stents by struts. FIG. 3 is a view for explaining the relationship between the expanded loop stent and the strut.

  Prior to describing the joint structure according to the embodiment of the present invention, the configuration of a stent in which a plurality of loop stents are connected will be briefly described.

  As shown in FIGS. 2 and 3, the stent 1 has a plurality of loop stents 3 formed in a loop shape by butt welding the end surfaces of the stent main line 2 bent into a zigzag shape, and these loops are arranged in series. The stent 3 is configured to be connected through at least two struts 4. A stabilizer hook 5 is connected to the loop stent 3 located at the head.

  In the butt weld portion of the stent main line 2 in the loop stent 3 and in the vicinity thereof, the austenite structure elongated in a fiber shape becomes a coarse granular structure due to the heat effect of welding, and the strength is lowered. For this reason, the protective pipe 6 is arrange | positioned in the welding part and its vicinity, and the degradation part by welding is reinforced with this protective pipe 6. FIG.

  In addition, a joint pipe 7 is disposed at a connection portion between the loop stent 3 and the strut 4 and a connection portion between the loop stent 3 and the stabilizer hook 5, and the stent main line 2 and the relationship as described later are connected to the joint pipe 7. The strut 4 or the stabilizer hook 5 in which the stop portion is formed is inserted and connected integrally by caulking, and the locking portion is locked to the joining pipe 7.

  The stent main wire 2 constituting the loop stent 3 is made of SUS316L, which is preferably used as stainless steel for implants, by extending the tissue into a fiber shape by cold drawing, thereby exerting work hardening and mechanical properties. Improved materials are used. In addition, the strut 4 and the stabilizer hook 5, the protective pipe 6 and the joint pipe 7 are also made of austenitic stainless steel wire material similar to the main stent wire 2, particularly a wire material made of SUS316L, and the structure is extended into a fiber shape by cold drawing. Materials are used.

  Although the thickness of the wire constituting the loop stent 3, the strut 4, and the stabilizer hook 5 varies depending on the organ to be placed, in this embodiment, the stent main line of the loop stent 3 has a diameter of about 0.4 mm to about 0.5 mm. The strut 4 and the stabilizer hook 5 have a diameter of about 0.5 mm.

  The joint pipe 7 is inserted into the stent main line 2 after the stent main line 2 is formed in a zigzag manner and before the end portion is welded. For this reason, the joining pipe 7 needs to be long enough to easily pass through the minimum radius portion (zigzag bent portion) of the stent main line 2 formed in a zigzag shape, and has a short length. A plurality of unit pipes are connected to form a joined pipe 7. For example, when the diameter of the stent main line 2 is 0.45 mm, the length of the unit pipe constituting the joining pipe 7 is set to 0.98 mm, and the joining pipe 6 is constructed by connecting three unit pipes. ing.

  Next, the connection structure in the stent 1 will be described with reference to FIG. In addition, the connection part in the stent 1 is each formed in the connection site | part of the loop stent 3 and the strut 4, the connection site | part of the loop stent 3 and the hook 5 for stabilizers, and the connection site of other linear parts which are not shown in figure. However, these connecting portions have the same configuration, and the configuration of the connecting portion between the stent main line 2 and the strut 4 of the loop stent 3 will be described as a representative.

  The connecting portion of the stent 1 according to the present embodiment is configured by inserting and caulking the stent main line 2 and the strut 4 of the loop stent 3 through the joining pipe 7, and the engaging portion penetrates the joining pipe 7 of the strut 4. It is comprised by the folding | turning edge part 11 formed in the edge part 4a.

  The joining pipe 7 has three unit pipes 7a to 7c having the same size and material, and two auxiliary pipes 7d and 7e arranged on both sides in the longitudinal direction of the unit pipes 7a to 7c. Configured. Each of the pipes 7 a to 7 e is inserted in advance into the main stent line 2 of the loop stent 3, and has moved along the main stent line 2 to a position to be a connecting portion for connecting the strut 4.

  The end 4a of the strut 4 has a predetermined length range that has been softened in advance by annealing, and is disposed along the main stent line 2 so as to penetrate the joint pipe 7 and protrude from the joint pipe 7. A folded end portion 11 is formed by folding the end portion 4a 180 degrees, and the folded end portion 11 constitutes a locking portion. The strut 4 in which the folded end portion 11 is formed is connected to the stent main line 2 by caulking the joining pipe 7.

  The folded end portion 11 is configured by folding the end portion 4a of the strut 4 through the joint pipe 7 and then folding back 180 degrees in a direction not interfering with the stent main line 2, that is, in a direction away from the stent main line 2. ing. Therefore, at the site where the folded end wedge 11 is formed, the thickness of the stent 1 is a size obtained by adding twice the thickness of the strut 4 to the thickness of the main stent line 2 compared with the other sites. It will be big.

  For this reason, when the portion of the stent 1 where the folded end portion 11 is formed moves relative to other adjacent parts when the stent 1 is placed in the affected area, There is a risk of adverse effects such as being caught on parts or causing large friction.

  For this reason, the chamfered portion 11a is formed by chamfering the outer edge of the folded end portion 11, that is, the edge opposite to the main stent line 2 at the portion where the folded end portion 11 is formed, into a curved surface. ing.

  Naturally, the chamfered portion 11a of the folded end portion 11 may be formed at least on the outer side, and may be formed on both side surfaces. Further, as described above, the chamfered shape is not limited to the curved R chamfer, but may be a C chamfer or a chamfer with an edge simply made to be an obtuse angle. Further, the shape in the case of the R chamfer need not be strictly an arc shape, and may be a chamfer formed by a curve. Similarly, in the case of C chamfering, it is not necessary to have a chamfered shape of exactly 45 degrees.

  Thus, by forming the chamfered portion 11 a at least outside the folded end portion 11, when the stent 1 is placed in the affected area, the folded end portion 11 moves relative to other adjacent components. Even if it occurs, there is no adverse effect that the folded end 11 is damaged to other parts.

  In addition, the operation | work which forms the chamfering part 11a in the folding | turning end part 11 may be performed manually using a file, and may be press-molded simultaneously when the joining pipe 7 is caulked. However, in order to eliminate the possibility of damaging other parts, it is preferable to perform grinding rather than press molding.

  Next, a procedure for configuring the connection unit will be described. The joint pipe 7 that has been inserted through the stent main line 2 in advance is moved to a position where the strut 4 is to be connected, and the strut 4 having the end 4a annealed is inserted into the joint pipe 7 so that the end 4a protrudes. Then, after the end portion 4 protruding from the joint pipe 7 of the strut 4 is folded back 180 degrees to form the folded end portion 11, the position of the strut 4 with respect to the stent main line 2 is adjusted.

  After adjusting the position of the strut 4 with respect to the main stent line 2 (the position of the strut 4 with respect to the loop stent 3) in this way, the strut 4 is pulled in the direction of arrow a to engage the folded end portion 11 with the end surface of the joining pipe 7. In this state, the unit pipes 7a to 7c constituting the joining pipe 7 are firmly caulked and the auxiliary pipes 7d and 7e are caulked or crushed.

  As described above, the strut 4 can be connected to the main stent line 2 of the loop stent 3 by using the joining pipe 7. In the connection portion thus configured, the end surface of the strut 7 constituting the folded end portion 11 is chamfered. Further, the step formed between the main stent line 2 and the joint pipe 7 is made as small as possible so that the folded end portion 11 does not damage the balloon when expanding the diameter of the stent graft. Is done.

  As described above, the end surface of the strut 4 penetrating the joint pipe 7 is chamfered in advance, and the chamfered portion 11 a is formed at least outside the folded end portion 11. In other words, the end surface of the strut 4 has a function of abutting against the end surface of the joining pipe 7 when a tensile force is applied to counter the force. For this reason, the chamfering of the end surface of the strut 4 is of a deburring level. Therefore, by forming the chamfered portion 11a at the folded end portion 11 where the end portion 4a of the strut 4 is folded back, it is possible to reduce the possibility of damaging other adjacent components.

  The folded end portion 11 does not necessarily have to be formed prior to caulking by the joining pipe 7. After the strut 4 is inserted into the joining pipe 7 and the end portion 4a is projected, the joining pipe 7 is caulked, and thereafter The folded end portion 11 may be formed by folding the end portion 4a 180 degrees.

  Further, the connection position of the strut 4 in the stent main line 2 of the loop stent 3 and the position where the strut 4 is inserted and crimped into the joint pipe 7 may be left in the original circular shape, or flat. It may be formed into a shape.

  In the stent 1 having such a connecting portion, a force in the direction of arrow a shown in FIG. 3 acts on the strut 4, and even if the strut 4 tries to slide in the direction of arrow a in response to this force, the folded portion 11 is connected to the joint pipe. 7, the strut 4 is not detached from the joint pipe 7 because it is in contact with and locked to the end surface of the joint 7.

  In the joining pipe 7, the stent main line 2 constituting the loop stent 3 and the strut 4 are mainly connected by the unit pipes 7a to 7c, and the strut 4 bends at an abrupt angle with respect to the stent main line 2 by the auxiliary pipes 7d and 7e. Is preventing.

  Next, a procedure for indwelling the stent 1 to which the plurality of loop stents 3 are connected by the struts 4 and the stabilizer hooks 5 are connected to the affected part will be briefly described with reference to FIG.

  A cylindrical graft 21 is formed on the stent 1, and the diameter of the stent 1 is reduced in accordance with the inner diameter of the sheath 22. A dilator 23 is accommodated in the sheath 22, and a guide wire 24 whose tip is exposed to the outside is accommodated. A stabilizer hook 5 provided at the top of the stent 1 is hooked on a notch provided in the dilator 23.

  Then, the surgeon operates the operation portion at hand to fix the stabilizer hook 5 to the organ by the dilator 23, and in this state, the sheath 22 is pulled toward the hand, whereby the stent 1 is pulled out of the sheath 22 and expanded in diameter. However, it can be placed in the affected area to treat the affected area.

  Further, in the process in which the stent 1 is pulled out from the sheath 22 and the diameter of the graft 21 is increased, the relative position between the folded end portion 11 and the sheath 21 or the graft 22 constituting the joint portion between the stent main line 1 and the strut 4 is relatively small. Even when the movement occurs, the chamfered portion 11a is formed at the folded end portion 11, so that the folded end portion 11 adversely affects the drawing operation from the sheath 21 or damages the graft 22. There is no fear.

  Next, different embodiments of the engaging portions formed on the struts 4 at the connecting portions formed in the stent 1 will be described with reference to FIG. In the stent of the present invention, since the configuration (the configuration of the loop stent 3 and the strut 4) other than the shape and structure of the locking portion in the connection portion is the same, the structure of the connection portion will be described.

  In FIG. 4A, the enlarged diameter end portion 12 is formed at the end portion 4 a of the strut 4, and the engagement portion is configured by the enlarged diameter end portion 12. The enlarged diameter end portion 12 can be formed by press working, and can be formed prior to inserting the strut 4 into the joining pipe 7 by selecting the diameter of the joining pipe 7. .

  As described above, when the engaging portion including the enlarged diameter end portion 12 is formed at the end portion 4 a of the strut 4, the enlarged diameter end portion 12 is brought into contact with and engaged with the end surface of the joining pipe 7. Even when a force in the direction of pulling out from the joining pipe 7 is applied, it will not be detached.

  Further, the enlarged diameter end portion 12 is formed with a chamfered portion 12a composed of a C surface on a surface (outside) opposite to the surface facing the main stent line 2 and on both side surfaces of the surface. Therefore, it is possible to reduce the risk of damaging other adjacent components.

  FIG. 2B shows a bent end 13 formed by bending the end 4 a of the strut 4 at a substantially right angle, and the bent end 13 constitutes a locking portion. The bent end 13 may be formed before the strut 4 is inserted into the joining pipe 7 or may be formed after the joining pipe 7 is inserted and caulked.

  In this way, when the locking portion including the bent end portion 13 is formed at the end portion 4 a of the strut 4, the bent end portion 13 is locked in contact with the end surface of the joining pipe 7. Even when a force in the direction of pulling out from the joining pipe 7 is applied, it will not be detached.

  Further, the bent end portion 13 is formed with a chamfered portion 13a having an obtuse angled surface (outside) opposite to the surface facing the main stent line 2. Therefore, it is possible to reduce the risk of damaging other adjacent components.

  In the connection structure of the stent main line and the linear part according to the present invention, when the stent is pulled out from the sheath when the stent is placed in the affected part, the connection part of the stent main line and the linear part may damage other parts, There is no adverse effect on the drawing work. Further, even if a force acts on the connection portion between the stent main line and the linear part, there is no possibility that the strut is detached from the joint pipe by this force. For this reason, it is advantageous when used when constructing a stent to be placed in the body for a long time.

It is a figure explaining the structure of a connection part. It is a figure explaining the example of the relationship of the stent and sheath which comprised the some loop stent connected by the strut. It is a figure explaining the relationship between the expanded loop stent and a strut. It is a figure explaining the structure of the connection part of the stent which concerns on 2nd Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Stent 2 Stent main line 3 Loop stent 4 Strut 4a End 5 Stabilizer hook 6 Protective pipe 7 Joint pipe 7a-7c Unit pipe 7d, 7e Auxiliary pipe 11 Return end part 11a-13a Chamfer part 12 Expanded end part 13 Bending End 21 Graft 22 Sheath 23 Dilator 24 Guide wire

Claims (1)

The main line of the stent and the linear part are connected via a joining pipe, and the end of the linear part that penetrates the joining pipe is folded, bent, or expanded in diameter, and the folded end part or the folded end part, Alternatively, a connecting portion structure between the main stent line and the linear component, wherein at least the outer side of the expanded end portion is chamfered.

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