WO2018180209A1

WO2018180209A1 - Medical device

Info

Publication number: WO2018180209A1
Application number: PCT/JP2018/008112
Authority: WO
Inventors: 阪川洋一; 伊藤祐貴; 生野恵理; 秋山真洋
Original assignee: テルモ株式会社
Priority date: 2017-03-28
Filing date: 2018-03-02
Publication date: 2018-10-04

Abstract

This medical device (10) is provided with a sheath (12) for passing between a blood vessel wall (120La) that is connected to an aneurysm (122a) and a stent graft (100) indwelled in the aneurysm (122a), in order to deliver an embolus (130) to the inside of the aneurysm (122a). The sheath (12) has: a sheath body (16) to be arranged between the stent graft (100) and the blood vessel wall (120La); and a helical sheath protrusion (20) that is provided on the external circumferential surface of a tip shaft part (17) so as to come into contact with a strut (106) of the stent graft (100).

Description

Medical device

The present invention relates to a medical device including a catheter for delivering an embolus into an aneurysm through a blood vessel wall connected to the aneurysm and an expansion body placed in the aneurysm.

In recent years, a stent graft, in which an expandable stent is locked to a tubular graft (artificial blood vessel), is expanded in the aortic aneurysm and closely adhered to the blood vessel wall, thereby circulating blood in the stent graft and in the aneurysm (aneurysm). Stent graft insertion is performed to block blood flow to the blood vessel wall between the stent graft and the stent graft (see Japanese Patent Application Laid-Open No. 2014-12135). It is known that in stent graft insertion, a so-called type 2 endoleak complication may occur, in which blood flows back into the aneurysm from the side branch of the aortic aneurysm.

As a treatment for such type 2 endoleak, treatment called Perigraft (Perigraft) (Motoki Nakai, MD, PhD, Akira Ikoma, MD, PhD, Morio Sato, MD, PhD, Hirotatsu Sato, MD, Yoshiharu Nishimura, MD , PhD, and Yoshitaka Okamura, MD, PhD, "Prophylactic Intraoperative Embolization of Abdominal Aortic Aneurysm Sacs Using N-Butyl Cyanoacrylate / Lipiodol / Ethanol Mixture with Proximal Neck Aortic Balloon Occlusion during Endovascular Abdominal Aortic Repair", Prophylactic Sac Embolization with NBCA / Lipiodol / Ethanol during EVAR, July 2016, Vol. 27, No. 7, p. 954-960) and treatment called Transealing or Transsealing (hereinafter referred to as Transsealing) (G. Coppi, G. Saitta, G. Coppi, S. Gennai, A. Lauricella, R. Silingardi, `` Transealing: A Novel and Simple Technique for Embolization of Type 2 Endoleaks Through Direct Sac Access From the Distal Stent-graft Landing Zone ”, European Journal of Vascular and Endovascular Surgery, April 2014, Volume 47, No.4, p.394-401).

In the perigraft, the distal end of the long catheter (sheath) is placed between the contracted stent graft and the vessel wall, and the stent graft is expanded to place the distal end of the sheath in the aneurysm. An embolus is introduced into the aneurysm.

In the transsealing, the catheter (sheath) is pushed forward with a guide wire between the expanded stent graft and the blood vessel wall, the distal end of the sheath is left in the aneurysm, and the embolus is introduced into the aneurysm through the sheath.

In the above-described perigraft and transceiling, when the embolus is introduced into the aneurysm, a reaction force acting in the proximal direction acts on the sheath, so that the distal end position of the sheath may be displaced in the proximal direction (the first Task).

Also, in transsealing, when inserting a sheath between an expanded stent graft and a blood vessel wall, an excessive force may act in the axial direction to cause the sheath to bend. Therefore, there is a possibility that the sheath cannot be smoothly inserted between the expanded stent graft and the blood vessel wall (second problem).

Furthermore, when a guide wire is inserted between the expanded stent graft and the blood vessel wall prior to the sheath, the guide wire becomes easier to insert as the hardness of the guide wire is increased. However, the blood vessel wall may be damaged by the guide wire. There is a problem that it becomes higher (third problem).

The present invention has been made in view of such problems, and an object thereof is to provide a medical device that can solve at least one of the first to third problems.

In order to achieve the above object, a medical device according to the present invention includes a catheter that can be placed between a blood vessel wall connected to an aneurysm and an expansion body placed in the blood vessel connected to the aneurysm. The catheter has a flexible and long shaft main body, and an outer peripheral surface of a distal shaft portion constituting at least a distal end portion of the shaft main body so as to contact a strut constituting the expansion body. And a shaft projection that spirally circulates around the shaft body in the circumferential direction.

According to such a configuration, when the shaft protrusion is positioned between the expansion body and the blood vessel wall when the embolus in the aneurysm is introduced in the perigraft and the transsealing, the proximal end of the shaft main body among the shaft protrusions A direction-oriented side surface (hereinafter referred to as “proximal side surface”) can be hooked on the strut of the expansion body. As a result, it is possible to receive the reaction force in the proximal direction acting on the catheter when the embolus is delivered into the aneurysm with the expansion body, so that the distal end position of the shaft body can be prevented from shifting in the proximal direction. it can. Therefore, the embolus can be reliably introduced into the aneurysm. That is, in this case, the first problem can be solved.

Further, in the transceiling, when the shaft body is inserted between the expanded body in the expanded state and the blood vessel wall, the shaft protrusion is turned into the strut by rotating the shaft with the proximal end side surface of the shaft protrusion in contact with the strut. Because the shaft rotates while pushing in the proximal direction, a reaction force in the distal direction from the strut acts on the shaft protrusion. That is, the rotational force input to the proximal end side of the catheter is converted into a propulsive force at the distal shaft portion. Therefore, the shaft body can be smoothly advanced between the expanded body in the expanded state and the blood vessel wall. In this case, since it is not necessary to push the proximal end side of the catheter excessively in the distal direction, the deflection of the shaft body can be suppressed. That is, the second problem can be solved.

Also, in the transceiling, when a guide wire is inserted between the expanded body in the expanded state and the blood vessel wall in advance of the shaft body, the guide wire can be pushed forward with the proximal end side surface of the shaft protrusion hooked on the strut. it can. At this time, since the expansion body can receive the reaction force in the proximal direction that acts on the catheter when the guide wire is advanced, the guide wire can be smoothly advanced without excessively increasing the hardness of the guide wire. it can. That is, the third problem described above can be solved.

Further, in the perigraft and transceiling, when the catheter is removed, the side surface (hereinafter referred to as the “front end side surface”) of the shaft projection facing the distal direction is in contact with the strut of the expanded body in the expanded state. By rotating (rotating in the direction opposite to the rotation direction at the time of insertion of the catheter in transiling), the shaft protrusion rotates while pushing the strut in the distal direction, so that the reaction force in the proximal direction from the strut is applied to the shaft protrusion. Works. Accordingly, the shaft body can be smoothly retracted between the expanded body in the expanded state and the blood vessel wall. Therefore, the catheter can be easily removed.

In the above medical device, the catheter has a sheath including a sheath body as the shaft body and a sheath protrusion as the shaft protrusion, and the sheath protrusion delivers an embolus into the aneurysm. In doing so, it may be provided so as to be positioned between the expansion body and the blood vessel wall.

According to such a configuration, since the expansion body can receive the reaction force in the proximal direction acting on the sheath when the embolus is delivered into the aneurysm in the perigraft and the transsealing, the distal end position of the sheath main body can be received. Can be prevented from shifting in the proximal direction. Therefore, the embolus can be reliably introduced into the aneurysm.

Said medical device WHEREIN: The base end side surface which orient | assigns the base end direction of the said sheath among the said sheath protrusion is a flat surface extended in the direction orthogonal to the axis line of the said sheath main body, or the protrusion end of the said sheath protrusion The flat surface which inclines in the base end direction of the said sheath main body toward may be sufficient.

According to such a configuration, it is possible to efficiently transmit force between the proximal end side surface of the sheath projection and the strut.

In the above-described medical device, the sheath protrusion may extend to the distal end portion of the distal shaft portion.

According to such a configuration, the tip shaft portion can be smoothly inserted between the expanded stent graft and the blood vessel wall in the transceiling. Further, in the perigraft and transceiling, the distal shaft portion can be smoothly removed from between the expanded stent graft and the blood vessel wall.

In the above-described medical device, the distal end of the sheath protrusion is configured such that a protrusion length of the distal end portion of the sheath protrusion with respect to the outer peripheral surface of the distal end shaft portion decreases toward one end in the extending direction of the spiral. You may connect smoothly with the outer peripheral surface of a shaft part.

According to such a configuration, the tip shaft portion can be smoothly inserted between the expanded stent graft and the blood vessel wall in the transsealing. In addition, it is possible to suppress an extra force from acting on the blood vessel wall and the stent graft when the sheath rotates.

In the above medical device, the catheter includes a dilator that is removably inserted into the sheath, and the dilator protrudes further to the distal end side than the distal end of the sheath body in a state of being inserted into the sheath. A long hollow dilator main body having flexibility, and provided on an outer peripheral surface of a tip protruding portion located on the tip end side of the sheath main body of the dilator main body, the dilator main body spirally in a circumferential direction And a dilator protrusion that circulates.

According to such a configuration, in the transceiling, the tip protruding portion of the dilator main body having an outer diameter smaller than that of the sheath can be inserted in advance between the expanded body in the expanded state and the blood vessel wall. And the sheath body can be more smoothly inserted between the blood vessel wall and the blood vessel wall. At this time, by rotating the dilator while the base end side surface of the dilator protrusion is in contact with the strut, the dilator protrusion rotates while pushing the strut in the base end direction, so that the rotational force of the dilator is converted into propulsive force. . Therefore, the dilator body can be smoothly advanced between the expanded body in the expanded state and the blood vessel wall. In this case, since it is not necessary to excessively push the proximal end side of the dilator in the distal direction, the bending of the dilator body can be suppressed.

Further, when the dilator main body and the sheath main body are advanced between the expanded body in the expanded state and the blood vessel wall, the dilator protrusion and the sheath protrusion push the strut in the proximal direction, so that force is concentrated on a part of the strut. You can avoid doing that. Thereby, it can suppress that a stent graft bends (kinks).

Furthermore, in the transceiling, when a guide wire is inserted between the expanded body in an expanded state and the blood vessel wall prior to the dilator body, the guide wire can be pushed forward while the proximal end side surface of the dilator protrusion is hooked on the strut. it can. At this time, since the expansion body can receive the reaction force in the proximal direction acting on the dilator when the guide wire is advanced, the guide wire can be smoothly advanced without excessively increasing the hardness of the guide wire. it can.

Furthermore, after the distal end of the sheath is advanced to a predetermined position in the aneurysm, the dilator is removed from the sheath, thereby introducing the embolus into the aneurysm through the lumen of the sheath larger than the lumen of the dilator. be able to.

Said medical device WHEREIN: The base end side surface which faces the base end direction of the said dilator among the said dilator protrusion is a flat surface extended in the direction orthogonal to the axis line of the said dilator main body, or the protrusion end of the said dilator protrusion The flat surface which inclines in the base end direction of the said dilator main body toward this may be sufficient.

According to such a configuration, it is possible to efficiently transmit force between the proximal end side surface of the dilator protrusion and the strut.

In the above medical device, the pitch of the dilator projection and the pitch of the sheath projection may be substantially the same.

According to such a configuration, when the dilator main body and the sheath main body are advanced between the expanded body in the expanded state and the blood vessel wall, a plurality of the base end side surfaces of the dilator projection and the base end side surface of the sheath projection are provided in the transsealing. The strut can be contacted efficiently.

In the above medical device, the proximal end of the dilator projection and the distal end of the sheath projection may have substantially the same circumferential phase.

According to such a configuration, the proximal end side surface of the dilator projection and the proximal end side surface of the sheath projection can be more efficiently brought into contact with a plurality of struts.

The medical device may include a rotation restricting portion that restricts relative rotation between the dilator and the sheath.

According to such a configuration, it is possible to suppress the dilator protrusion and the sheath protrusion from being displaced from each other in the circumferential direction.

In the above medical device, the dilator protrusion may extend to the tip of the tip protrusion.

According to such a configuration, the tip of the tip protrusion can be smoothly inserted between the expanded stent graft and the blood vessel wall in the transceiling.

In the above-described medical device, the outer peripheral surface of the dilator protrusion has a protrusion length with respect to an outer peripheral surface of the tip protrusion portion at a tip portion of the dilator protrusion that decreases toward one end in a spiral extending direction. You may connect smoothly with the outer peripheral surface of a protrusion part.

According to such a configuration, the tip end portion of the tip protruding portion can be smoothly inserted between the expanded body in the expanded state and the blood vessel wall in the transceiling. It is possible to suppress an excessive force from acting on the blood vessel wall and the expansion body when the dilator rotates.

In the above-described medical device, the catheter includes a flexible and long sheath, and a dilator removably inserted into the sheath, and the dilator is inserted into the sheath. A dilator main body as a long shaft body having flexibility that protrudes to the front end side from the front end of the sheath in the inserted state, and the front end of the dilator main body that is positioned on the front end side of the sheath A dilator protrusion as the shaft protrusion that is provided on the outer peripheral surface of the tip projecting portion constituting the shaft portion and spirals around the dilator body in the circumferential direction may be included.

According to such a configuration, the same effect as the above-described dilator can be obtained.

According to the present invention, when the shaft protrusion is positioned between the expansion body and the blood vessel wall when the embolus is introduced into the aneurysm, the distal end position of the sheath body is shifted in the proximal direction in the perigraft and the transsealing. That can be suppressed. Further, in the transceiling, the deflection of the shaft body can be suppressed and the guide wire can be smoothly advanced. Further, the shaft body can be smoothly retracted in the perigraft and transceiling.

1 is a perspective view of a medical device according to an embodiment of the present invention. FIG. 2 is a partially omitted vertical sectional view of the medical device of FIG. 1. It is an enlarged plan view of the front end side of the medical device of FIG. 4A is an enlarged cross-sectional view of a sheath protrusion (dilator protrusion), and FIG. 4B is a cross-sectional view taken along line IVB-IVB in FIG. 5A is a cross-sectional view taken along the line VA-VA of FIG. 2, and FIG. 5B is a plan view of the expanded stent graft. FIG. 6A is a first explanatory diagram of a perigraft, and FIG. 6B is a second explanatory diagram of a perigraft. FIG. 7A is a third explanatory diagram of the perigraft, and FIG. 7B is a fourth explanatory diagram of the perigraft. FIG. 8A is a first explanatory diagram of transceiling, and FIG. 8B is a second explanatory diagram of transceiling. 9A is a third explanatory view of transceiling, and FIG. 9B is a fourth explanatory view of transceiling. It is 1st cross-sectional explanatory drawing explaining the effect of the said medical device. It is 2nd cross-sectional explanatory drawing explaining the effect of the said medical device. It is 3rd cross-sectional explanatory drawing explaining the effect of the said medical device. It is a perspective view which shows the modification of the catheter of a medical device.

Hereinafter, preferred embodiments of the medical device according to the present invention will be described with reference to the accompanying drawings.

As shown in FIGS. 7B and 9B, the medical device 10 according to the present embodiment is placed on the blood vessel wall 120La connected to the abdominal aortic aneurysm (hereinafter referred to as “aneurysm 122a”) and the aneurysm 122a. The embolus 130 is delivered to the aneurysm 122a through the stent graft 100. However, the medical device 10 can also be used for procedures such as a thoracic aortic aneurysm using the stent graft 100, for example.

First, the stent graft 100 as an expansion body will be briefly described with reference to FIG. 5B. Note that the stent graft 100 shown in FIG. 5B is in an expanded state. As shown in FIG. 5B, the stent graft 100 includes a cylindrical graft 102 as an artificial blood vessel, and a stent 104 locked to the outer peripheral surface of the graft 102 by sewing or the like. The stent 104 is formed by providing a plurality of linear struts 106 extending in a wave shape (zigzag shape) and circulating around the graft 102 so as to be separated from each other in the axial direction of the stent graft 100. That is, each strut 106 includes a plurality of straight portions that are inclined at an acute angle with respect to the axial direction of the graft 102. The cross section of each strut 106 is formed in a circular shape (see FIG. 10).

As shown in FIGS. 1 and 2, the medical device 10 includes a catheter 11 having a long sheath 12 and a dilator 14 removably inserted into the sheath 12. The sheath 12 includes a sheath body 16 as a long hollow shaft body, and a sheath hub 18 provided at the proximal end of the sheath body 16.

The sheath body 16 is a tube having a lumen 16a having a substantially constant inner diameter d1 over the entire length. The sheath body 16 has flexibility (softness) so that it can easily follow a meandering blood vessel, and has an appropriate rigidity that cannot be bent in the blood vessel. Examples of the constituent material of the sheath body 16 include polyolefin (for example, polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more thereof), polyvinyl chloride, Examples thereof include polymer materials such as polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane, polyurethane elastomer, polyimide, fluororesin, or a mixture thereof, or the above-described two or more polymer materials. The sheath body 16 may be a multilayer tube in which a plurality of these materials are stacked.

The outer peripheral surface of the distal end region extending a predetermined length in the proximal direction from the distal end of the sheath body 16 is tapered toward the distal end. The outer diameter of the proximal end side of the distal end region of the sheath body 16 is formed to be constant. For example, the sheath body 16 has an inner diameter d1 of 1.5 mm or more and an outer diameter d2 (an outer diameter on the proximal end side of the distal end region of the sheath body 16) of about 9 Fr (3 mm). However, the inner diameter d1 and the outer diameter d2 of the sheath body 16 can be arbitrarily set. The distal end surface 16b of the sheath body 16 is curved to suppress damage to the blood vessel wall. The distal shaft portion 17 constituting at least the distal end portion of the sheath body 16 is disposed between the stent graft 100 and the blood vessel wall 120La. A sheath projection 20 is provided on the outer peripheral surface of the distal end shaft portion 17 of the sheath body 16 so as to spirally surround the sheath body 16 in the circumferential direction so as to contact the strut 106 of the expanded stent graft 100. That is, the sheath projection 20 as the shaft projection is not provided at the proximal end portion of the sheath body 16. However, the extending range of the sheath projection 20 can be arbitrarily set.

As shown in FIGS. 2 and 3, the sheath projection 20 is formed by, for example, winding a belt-like flat plate around the outer peripheral surface of the sheath body 16 in a spiral manner and joining them. However, the sheath protrusion 20 may be formed by cutting the outer peripheral surface of the sheath body 16. Examples of the constituent material of the sheath protrusion 20 include a metal or a resin that is the same as or different from that of the sheath body 16. As the metal material constituting the sheath projection 20, for example, a metallic biomaterial such as stainless steel, cobalt chromium alloy, titanium alloy or the like is preferably used.

As shown in FIG. 4A, the sheath projection 20 connects the proximal end side surface 20a directed in the proximal direction of the sheath 12, the distal end side surface 20b directed in the distal end direction of the sheath 12, and the proximal end side surface 20a and the distal end side surface 20b. And an outer peripheral surface 20c. The chamfering process is applied to the boundary portion between the proximal end side surface 20a and the outer peripheral surface 20c and the boundary portion between the distal end side surface 20b and the outer peripheral surface 20c in order to prevent damage to the blood vessel wall.

Each of the proximal end side surface 20 a and the distal end side surface 20 b is a flat surface extending in a direction orthogonal to the axis of the sheath body 16. However, the proximal end side surface 20a may be a flat surface that inclines in the proximal end direction of the sheath body 16 toward the protruding end (projecting direction) of the sheath projection 20. In this case, transmission of force between the proximal end side surface 20a of the sheath projection 20 and the strut 106 can be performed efficiently. Further, the distal end side surface 20b may be a flat surface inclined toward the distal end direction of the sheath body 16 toward the protruding end (projecting direction) of the sheath projection 20. In this case, transmission of force between the distal end side surface 20b of the sheath projection 20 and the strut 106 can be performed efficiently.

2 and 3, the sheath projection 20 extends to the distal end portion of the distal shaft portion 17. As shown in FIG. 4B, the outer peripheral surface 20 c of the sheath projection 20 has a protrusion length with respect to the outer peripheral surface of the distal shaft portion 17 at the distal end portion of the sheath projection 20 that decreases toward one end (starting end) in the spiral extending direction. Thus, the outer peripheral surface of the tip shaft portion 17 is smoothly connected. That is, there is no step between the distal end portion of the sheath projection 20 and the outer peripheral surface of the distal shaft portion 17. Specifically, the outer peripheral surface 20c of the distal end portion of the sheath projection 20 is inclined toward the distal shaft portion 17 side (inward in the radial direction) so as to become thinner toward the spiral start end.

Further, as shown in FIG. 1, the outer peripheral surface 20c of the sheath projection 20 has a protruding length with respect to the outer peripheral surface of the sheath body 16 at the proximal end portion of the sheath projection 20 toward the other end (terminal) in the spiral extending direction. By becoming smaller, it is smoothly connected to the outer peripheral surface of the tip shaft portion 17. That is, there is no step between the proximal end portion of the sheath projection 20 and the outer peripheral surface of the distal end shaft portion 17. Specifically, the outer peripheral surface 20c of the proximal end portion of the sheath projection 20 is inclined toward the distal shaft portion 17 side (inward in the radial direction) so as to become thinner toward the end of the spiral.

However, a recess in which the distal end portion of the sheath projection 20 is disposed is formed on the outer circumferential surface of the distal shaft portion 17 so that the outer circumferential surface 20c of the distal end portion of the sheath projection 20 is smoothly connected to the outer circumferential surface of the distal shaft portion 17. May be. Further, a recess in which the proximal end portion of the sheath projection 20 is disposed on the outer peripheral surface of the distal shaft portion 17 so that the outer peripheral surface 20c of the proximal end portion of the sheath projection 20 is smoothly connected to the outer peripheral surface of the distal shaft portion 17. It may be formed.

In FIG. 4A, at the intermediate portion in the extending direction of the sheath projection 20, the protruding length of the proximal side surface 20a (the protruding length of the flat portion of the proximal end side surface 20a with respect to the outer peripheral surface of the distal shaft portion 17) and the protruding length of the distal side surface 20b. (The protruding length of the flat portion of the base end side surface 20a with respect to the outer peripheral surface of the distal end shaft portion 17) is set to the same height h over the entire length of the intermediate portion. In this case, it is possible to efficiently transmit force between the sheath projection 20 and the strut 106 and to suppress the sheath projection 20 from hitting the graft 102. The height h is preferably larger than the radius r (see FIG. 11) of the strut 106 and smaller than the diameter of the strut 106. That is, for example, when the diameter of the strut 106 is 0.4 mm, the height h is set in a range larger than 0.2 mm and smaller than 0.4 mm. When the height h is 0.1 mm or less, it becomes smaller than the average thickness of the aortic intima of men over 60 years old, so that damage to the blood vessel wall can be suppressed. However, the height h can be arbitrarily set.

As shown in FIG. 3, the helical angle θ1 of the sheath projection 20 (the angle formed by the line segment orthogonal to the axis of the sheath 12 and the sheath projection 20) is the inclination angle θ2 of the strut 106 of the expanded stent graft 100 ( The angle is set to be equal to or close to the angle formed between the line segment orthogonal to the axis of the stent graft 100 and the straight portion of the strut 106 (see FIG. 5B). In this case, the proximal end side surface 20 a and the distal end side surface 20 b of the sheath projection 20 can be efficiently brought into contact with the straight portion of the strut 106. The spiral angle θ1 of the sheath projection 20 is set to, for example, 30 ° to 45 °.

The pitch L1 of the sheath projection 20 (the distance between the proximal side surface 20a and the distal side surface 20b adjacent in the axial direction) is substantially constant over the entire length, and is larger than the distance L2 between the struts 106 adjacent in the axial direction of the stent graft 100. narrow. In this case, the proximal end side surface 20a of the sheath projection 20 can be efficiently brought into contact with the plurality of struts 106. Further, when the sheath 12 is removed from between the expanded stent graft 100 and the blood vessel wall 120La, the distal side surface 20b of the sheath projection 20 can be efficiently brought into contact with the plurality of struts 106. The pitch L1 of the sheath protrusion 20 is determined based on the outer diameter d2 of the sheath body 16 and the helical angle θ1 of the sheath protrusion 20.

As shown in FIGS. 1, 2, and 5A, the sheath hub 18 is formed in a hollow shape and has a lumen 18a through which the dilator 14 is inserted. Examples of the constituent material of the sheath hub 18 include the same materials as the constituent material of the sheath body 16. The sheath hub 18 is connected to the outer peripheral surface of the sheath body 16 and has an outer peripheral surface having an outer peripheral surface that is tapered toward the proximal direction, and an annular sheath side provided at the proximal end of the expanded diameter portion 22. And an engaging portion 24. An annular groove 26 is formed on the outer peripheral surface of the sheath side engaging portion 24. A key groove 28 extending along the axial direction of the sheath hub 18 is formed on the inner peripheral surface of the sheath side engaging portion 24. The key groove 28 is open to the proximal end surface of the sheath hub 18.

As shown in FIG. 1 and FIG. 2, the dilator 14 includes a long hollow dilator body 30 having flexibility and protruding toward the distal end side of the distal end of the sheath body 16 when inserted into the sheath 12. And a dilator hub 32 provided at the proximal end of the dilator body 30 and detachable from the sheath hub 18. That is, the dilator main body 30 is configured to be longer than the sheath main body 16, and protrudes by a predetermined length from the distal end of the sheath 12 to the distal end side when the dilator hub 32 is attached to the sheath hub 18.

The dilator body 30 is a tube having a lumen 30a having a substantially constant inner diameter d3 over its entire length. The dilator body 30 has flexibility (softness) so that it can easily follow a meandering blood vessel, and has an appropriate rigidity that cannot be bent in the blood vessel. Examples of the constituent material of the dilator body 30 include the same materials as the constituent material of the sheath body 16.

The inner diameter d3 of the dilator main body 30 is configured to be 0.46 mm (0.018 inch) or more so that the guide wire 110 can be inserted. However, the inner diameter d3 of the dilator body 30 can be arbitrarily set. The outer diameter of the dilator body 30 is set to a size that allows the dilator 14 to move in the axial direction with respect to the sheath 12. The distal end surface 30b of the dilator body 30 is curved to suppress damage to the blood vessel wall.

The distal protrusion 34 of the dilator main body 30 (the portion of the dilator main body 30 located on the distal side of the distal end of the sheath 12) is a stent graft 100 placed in a blood vessel connected to the aneurysm 122a and a blood vessel wall 120La connected to the aneurysm 122a. Inserted between. The outer peripheral surface of the tip protrusion 34 is gradually reduced in diameter toward the tip. On the outer peripheral surface of the tip protrusion 34, a dilator protrusion 36 that spirals around the dilator body 30 in the same direction as the spiral of the sheath protrusion 20 is provided. That is, the dilator projection 36 is not provided on the base end side of the tip protrusion 34 in the dilator body 30 (see FIG. 2).

As shown in FIGS. 2 and 3, the dilator protrusion 36 is formed by, for example, winding a belt-like flat plate around the outer peripheral surface of the tip protrusion 34 in a spiral manner and joining them. However, the dilator protrusion 36 may be formed by cutting the outer peripheral surface of the tip protrusion 34. The constituent material of the dilator protrusion 36 may be the same as the constituent material of the sheath protrusion 20.

As shown in FIG. 4A, the dilator protrusion 36 connects the base end side surface 36 a that faces the base end direction of the dilator 14, the front end side surface 36 b that points the front end direction of the dilator 14, and the base end side surface 36 a and the front end side surface 36 b. And an outer peripheral surface 36c. The chamfering process is applied to the boundary between the proximal end side surface 36a and the outer peripheral surface 36c and the boundary portion between the distal end side surface 36b and the outer peripheral surface 36c in order to prevent damage to the blood vessel wall.

Each of the proximal end side surface 36 a and the distal end side surface 36 b is a flat surface extending in a direction perpendicular to the axis of the dilator body 30. However, the base end side surface 36 a may be a flat surface that is inclined in the base end direction of the dilator main body 30 toward the protruding end (projecting direction) of the dilator protrusion 36. In this case, force transmission between the proximal end side surface 36a of the dilator protrusion 36 and the strut 106 can be efficiently performed. Further, the front end side surface 36 b may be a flat surface that inclines in the front end direction of the dilator main body 30 toward the protruding end (projecting direction) of the dilator protrusion 36. In this case, transmission of force between the tip side surface 36b of the dilator protrusion 36 and the strut 106 can be performed efficiently.

1 to 3, the dilator protrusion 36 extends to the tip of the tip protrusion 34. The outer peripheral surface 36c of the dilator protrusion 36 has a protrusion length with respect to the outer peripheral surface of the tip protrusion 34 at the tip of the dilator protrusion 36 becoming smaller toward one end (starting end) in the spiral extending direction. Smoothly connected to the outer peripheral surface. That is, there is no step between the tip of the dilator protrusion 36 and the outer peripheral surface of the tip protrusion 34. Specifically, the outer peripheral surface 36c at the tip of the dilator projection 36 is inclined toward the tip protrusion 34 (inward in the radial direction) so as to become thinner toward the spiral start.

In addition, the outer peripheral surface 36c of the dilator protrusion 36 has a distal end that protrudes toward the other end (termination) in the spiral extending direction with respect to the outer peripheral surface of the distal protrusion 34 at the proximal end of the dilator protrusion 36, thereby The projection 34 is smoothly connected to the outer peripheral surface. That is, there is no step between the base end portion of the dilator protrusion 36 and the outer peripheral surface of the tip protruding portion 34. Specifically, the outer peripheral surface 36c of the base end portion of the dilator protrusion 36 is inclined toward the tip protrusion 34 (in the radial direction) so as to become thinner toward the end of the spiral. Thereby, when the dilator 14 is removed from the sheath 12, it is possible to prevent the dilator protrusion 36 from being caught by the sheath body 16.

However, a recess in which the tip portion of the dilator projection 36 is disposed is formed on the outer peripheral surface of the tip protrusion portion 34 so that the outer peripheral surface 36c of the tip portion of the dilator projection 36 is smoothly connected to the outer periphery surface of the tip protrusion portion 34. May be. In addition, a recess in which the base end portion of the dilator projection 36 is disposed on the outer peripheral surface of the tip protrusion 34 so that the outer peripheral surface 36c of the base end portion of the dilator protrusion 36 is smoothly connected to the outer periphery of the tip protrusion 34. It may be formed.

3, the spiral angle θ3 of the dilator protrusion 36 (the angle formed by the line segment orthogonal to the axis of the dilator 14 and the dilator protrusion 36) is set to the same angle as the spiral angle θ1 of the sheath protrusion 20. That is, the spiral angle θ3 of the dilator protrusion 36 is set to be equal to or close to the inclination angle θ2 of the strut 106 of the expanded stent graft 100.

The pitch L3 (distance between the proximal side surface 36a and the distal side surface 36b adjacent to each other in the axial direction) of the dilator projection 36 is substantially constant over the entire length, and is substantially the same as the pitch L1 of the sheath projection 20. Further, the proximal end of the dilator protrusion 36 and the distal end of the sheath protrusion 20 have substantially the same circumferential phase. That is, the proximal end of the dilator protrusion 36 is smoothly connected to the distal end of the sheath protrusion 20 via the distal end surface 16 b of the sheath body 16.

As shown in FIGS. 1, 2 and 5A, the dilator hub 32 is formed in a hollow shape and has a lumen 32a through which the guide wire 110 is inserted. Examples of the constituent material of the dilator hub 32 include the same constituent materials as those of the dilator body 30. The dilator hub 32 is provided at the proximal end of the dilator main body 30 and can be attached to and detached from the sheath side engaging portion 24, and the gripping portion 40 extending from the dilator side engaging portion 38 in the proximal direction. And have. The dilator side engaging portion 38 includes an annular plate-shaped flange portion 42 provided at the base end of the dilator main body 30, a cylindrical portion 44 extending from the outer edge portion of the flange portion 42 in the distal direction, and the cylindrical portion 44. And an annular claw portion 46 protruding radially inward from the protruding end. A projecting portion 48 that projects in the distal direction and fits into the key groove 28 of the sheath side engaging portion 24 is provided on the surface of the flange portion 42 that faces the distal direction. The protrusion 48 and the key groove 28 function as a rotation restricting portion 50 that restricts relative rotation between the dilator 14 and the sheath 12. The protrusion 48 is connected to the outer peripheral surface of the dilator body 30. The claw portion 46 is fitted into the annular groove 26 of the sheath side engaging portion 24.

Next, the operation of the medical device 10 will be described. Here, first, a perigraft treatment using the medical device 10 in stent graft insertion for an aneurysm 122a (abdominal aortic aneurysm) will be described.

As shown in FIG. 6A, when performing stent graft insertion as a treatment for aneurysm 122a, the user (operator) inserts a guide wire 110a into the blood vessel from the buttocks, for example, to insert the right common iliac artery 120R, Advance to the descending thoracic aorta 124 via the abdominal aorta 122. Thereafter, the catheter 126a having the contracted first stent graft 100a at the distal end is advanced along the guide wire 110a through the right common iliac artery 120R to the abdominal aorta 122 to move the first stent graft 100a into the aneurysm 122a. To be located. In this state, the first stent graft 100a is expanded to bring the first stent graft 100a into close contact with the blood vessel wall 122b above the aneurysm 122a (the chest descending aorta 124 side) and the blood vessel wall 120Ra of the right common iliac artery 120R. . Then, the guide wire 110a and the catheter 126a are removed.

Subsequently, as shown in FIG. 6B, the guide wire 110 is inserted into the blood vessel from the buttocks and advanced into the aneurysm 122a via the left common iliac artery 120L. Next, the medical device 10 is moved until the distal end of the sheath body 16 reaches a predetermined position in the aneurysm 122a along the guide wire 110 with the guide wire 110 passed through the lumen 14a (see FIG. 2) of the dilator 14. Make it progress.

Then, as shown in FIG. 7A, a guide wire 110b is inserted into the blood vessel from the buttocks and advanced to the descending thoracic aorta 124 via the left common iliac artery 120L and the abdominal aorta 122. Thereafter, the catheter 126b provided with the second stent graft 100b in the contracted state is advanced to the abdominal aorta 122 through the left common iliac artery 120L along the guide wire 110b to expand the second stent graft 100b in the expanded state. 1 Insert into the connection opening 107 (see FIG. 6B) of the stent graft 100a.

Thereafter, the second stent graft 100b is expanded to connect the second stent graft 100b to the first stent graft 100a and to be in close contact with the blood vessel wall 120La of the left common iliac artery 120L. At this time, the distal end shaft portion 17 of the sheath body 16 is disposed between the expanded second stent graft 100b and the blood vessel wall 120La of the left common iliac artery 120L. Further, the second stent graft 100b is connected to the first stent graft 100a, whereby the inverted Y-shaped stent graft 100 is formed.

Next, the guide wire 110b and the catheter 126b are removed, and the guide wire 110 and the dilator 14 are removed from the sheath 12. Specifically, the engagement between the claw portion 46 of the dilator side engaging portion 38 and the sheath side engaging portion 24 is released, and the dilator hub 32 is pulled back with respect to the sheath hub 18 in the proximal direction. As a result, the sheath body 16 is left in the blood vessel.

Then, the embolus 130 is delivered into the aneurysm 122a through the lumen 12a of the sheath 12 (see FIG. 2). As the embolus 130, an embolic agent or a metal coil is used. When a coil is used as the embolus 130, a microcatheter (not shown) may be inserted into the lumen 12a of the sheath 12, and the embolus 130 may be delivered into the aneurysm 122a via the lumen of the microcatheter. Alternatively, the embolus 130 may be delivered into the aneurysm 122a via the lumen 14a of the dilator 14 with the dilator 14 left without being removed from the sheath 12.

After the introduction of the embolus 130 into the aneurysm 122a is completed, the user removes the sheath 12 by pulling it back in the proximal direction while rotating the sheath hub 18. When the sheath 12 is removed, the dilator 14 may be inserted into the sheath 12 and the dilator 14 and the sheath 12 may be removed together. Thereby, since the sheath 12 is supported by the dilator 14, the sheath 12 can be easily removed. Thus, by filling the embolus 130 in the aneurysm 122a in advance, type 2 endoleak in which blood flows backward from the aortic side branch 132 into the aneurysm 122a can be prevented.

Next, the transsealing treatment using the medical device 10 performed when a type 2 endoleak is recognized after the stent-graft insertion for the aneurysm 122a (abdominal aortic aneurysm) will be described.

In this case, as shown in FIG. 8A, an inverted Y-shaped stent graft 100 has already been placed in the aneurysm 122a. That is, the first stent graft 100a is closely attached to the blood vessel wall 122b above the aneurysm 122a of the abdominal aorta 122 and the blood vessel wall 120Ra of the right common iliac artery 120R, and the second stent graft 100b is a blood vessel of the left common iliac artery 120L. It is in close contact with the wall 120La.

In transceiling, the guide wire 110 is inserted into the blood vessel from the buttocks and advanced to the left common iliac artery 120L. Next, the medical device 10 is advanced along the guide wire 110 with the guide wire 110 passed through the lumen 14a of the dilator 14 until the tip of the dilator main body 30 is located immediately before the second stent graft 100b.

Thereafter, the medical device 10 is inserted while the guide wire 110 is advanced between the second stent graft 100b and the blood vessel wall 120La of the left common iliac artery 120L (see FIG. 8B). At this time, the user advances the medical device 10 by rotating the sheath hub 18. In addition, the guide wire 110 and the medical device 10 are alternately advanced by a predetermined length. Then, after the distal end of the sheath body 16 is placed at a predetermined position in the aneurysm 122a (see FIG. 9A), the guide wire 110 and the dilator 14 are removed.

Then, perform the same procedure as the perigraft procedure. That is, the embolus 130 is delivered into the aneurysm 122a through the lumen 12a of the sheath 12 (see FIG. 9B). As the embolus 130, an embolic agent (medicine) or a metal coil is used. When a coil is used as the embolus 130, a microcatheter (not shown) may be inserted into the lumen 12a of the sheath 12, and the embolus 130 may be delivered into the aneurysm 122a via the lumen of the microcatheter. Alternatively, the embolus 130 may be delivered into the aneurysm 122a via the lumen 14a of the dilator 14 with the dilator 14 left without being removed from the sheath 12.

Then, after the delivery of the embolus 130 into the aneurysm 122a is completed, the user removes the sheath 12 by pulling back the sheath hub 18 in the proximal direction while rotating the sheath hub 18 in the direction opposite to that at the time of introduction. When the sheath 12 is removed, the dilator 14 may be inserted into the sheath 12 and the dilator 14 and the sheath 12 may be removed together. Thereby, since the sheath 12 is supported by the dilator 14, the sheath 12 can be easily removed. Thus, when type 2 endoleak is recognized, the backflow of blood in the aneurysm 122a from the aortic side branch 132 can be suppressed by filling the embolus 130 into the aneurysm 122a.

The medical device 10 may be used for an intermediate procedure between the above-described perigraft and transceiling. Specifically, the second stent graft 100b is expanded and placed on the blood vessel wall 120La with the guide wire 110 placed in the aneurysm 122a, and then the medical device 10 is expanded along the guide wire 110 in the expanded state. You may make it insert between 2 stent graft 100b and blood vessel wall 120La.

Next, the effect of this embodiment will be described below.

The medical device 10 includes a catheter 11 that can be placed between a blood vessel wall 120La connected to an aneurysm 122a and a stent graft 100 placed in a blood vessel connected to the aneurysm 122a. The sheath 12 constituting the catheter 11 is in contact with a long sheath body 16 (shaft body) and a strut 106 constituting the stent 104 provided on the outer peripheral surface of the graft 102 constituting the stent graft 100. And a sheath projection 20 (shaft projection) that is provided on the outer peripheral surface of the tip shaft portion 17 that constitutes at least the tip portion of the sheath body 16 and spirals around the sheath body 16 in the circumferential direction.

Therefore, in the perigraft and transceiling, the proximal side surface 20a of the sheath projection 20 is placed on the strut of the stent graft 100 in a state where the sheath body 16 is disposed between the expanded stent graft 100 placed in the aneurysm 122a and the blood vessel wall 120La. 106 can be hooked. Accordingly, as shown in FIG. 10, the stent graft 100 can receive a proximal reaction force Fa acting on the sheath 12 when the embolus 130 is delivered into the aneurysm 122a. It is possible to prevent the position from shifting in the proximal direction. Therefore, the embolus 130 can be reliably introduced into the aneurysm 122a.

In addition, as shown in FIG. 11, in the transsealing, when the sheath body 16 is inserted between the expanded stent graft 100 and the blood vessel wall 120La, the proximal end side surface 20a of the sheath projection 20 is in contact with the strut 106. By rotating the sheath 12, the sheath projection 20 rotates while pushing the strut 106 in the proximal direction, so that a reaction force Fb in the distal direction from the strut 106 acts on the sheath projection 20. That is, the rotational force input to the proximal end side of the sheath 12 is converted into a propulsive force (reaction force Fb) by the distal shaft portion 17. Therefore, the sheath body 16 can be smoothly advanced between the expanded stent graft 100 and the blood vessel wall 120La. In this case, since it is not necessary to excessively push the proximal end side of the sheath 12 in the distal direction, the bending of the sheath body 16 can be suppressed.

Further, in the transsealing, when the guide wire 110 is inserted between the stent graft 100 in an expanded state and the blood vessel wall 120La prior to the sheath body 16, the proximal end side surface 20a of the sheath projection 20 is hooked on the strut 106. The guide wire 110 can be pushed forward. At this time, since the proximal graft reaction force acting on the sheath 12 when the guide wire 110 is advanced can be received by the stent graft 100, the guide wire 110 can be smoothly moved without excessively increasing the hardness of the guide wire 110. You can move forward.

Furthermore, as shown in FIG. 12, in the perigraft and transsealing, when the sheath 12 is removed, the sheath 12 is rotated while the distal end side surface 20b of the sheath projection 20 is in contact with the strut 106 of the expanded stent graft 100 (see FIG. The sheath projection 20 rotates while pushing the strut 106 in the distal direction by rotating the sheath projection 20 in the direction opposite to the rotation direction when the sheath 12 is inserted in the transceiling. Reaction force Fc acts. As a result, the sheath body 16 can be smoothly retracted between the expanded stent graft 100 and the blood vessel wall 120La. Therefore, the sheath 12 can be easily removed. Therefore, the type 2 endoleak of the aneurysm 122a can be effectively treated.

Since the proximal end side surface 20 a of the sheath projection 20 that faces the proximal direction of the sheath 12 extends in a direction perpendicular to the axis of the sheath body 16, the proximal end side surface 20 a of the sheath projection 20 and the strut 106 The transmission of force between them can be performed efficiently.

Since the sheath protrusion 20 extends to the distal end portion of the distal shaft portion 17, the distal shaft portion 17 can be smoothly inserted between the expanded stent graft 100 and the blood vessel wall 120La in the transsealing. Further, in the perigraft and transceiling, the distal end shaft portion 17 can be smoothly removed from between the expanded stent graft 100 and the blood vessel wall 120La.

The outer circumferential surface 20c of the sheath projection 20 is formed on the outer circumferential surface of the distal shaft portion 17 by the protrusion length of the distal end portion of the sheath projection 20 with respect to the outer circumferential surface of the distal shaft portion 17 becoming smaller toward one end in the spiral extending direction. It is connected smoothly. Thereby, the tip shaft portion 17 can be smoothly inserted between the stent graft 100 in the expanded state and the blood vessel wall 120La in the transsealing. Further, it is possible to suppress an extra force from acting on the blood vessel wall 120La and the stent graft 100 when the sheath 12 is rotated.

The medical device 10 includes a dilator 14 that is removably inserted into the sheath 12. The dilator 14 includes a long hollow dilator body 30 having flexibility and protruding from the distal end side of the sheath body 16 in a state of being inserted into the sheath 12, and the sheath body 16 of the dilator body 30. And a dilator protrusion 36 that is provided on the outer peripheral surface of the tip protrusion 34 located on the tip side and spirals around the dilator body 30 in the circumferential direction.

Thereby, in the transsealing, the distal protrusion 34 of the dilator body 30 having an outer diameter smaller than that of the sheath 12 can be inserted in advance between the expanded stent graft 100 and the blood vessel wall 120La. The sheath body 16 can be more smoothly inserted between the blood vessel wall 120La. At this time, by rotating the dilator 14 with the proximal side surface 36a of the dilator projection 36 in contact with the strut 106, the dilator projection 36 rotates while pushing the strut 106 in the proximal direction. Is converted into propulsion. Therefore, the dilator body 30 can be smoothly advanced between the expanded stent graft 100 and the blood vessel wall 120La. In this case, since it is not necessary to excessively push the proximal end side of the dilator 14 in the distal direction, the bending of the dilator body 30 can be suppressed.

When the dilator main body 30 and the sheath main body 16 are advanced between the expanded stent graft 100 and the blood vessel wall 120La, the dilator protrusion 36 and the sheath protrusion 20 push the strut 106 in the proximal direction. It is possible to avoid concentrating power on a part. Thereby, it can suppress that the stent graft 100 bends (kinks).

In the transsealing, when the guide wire 110 is inserted between the expanded stent graft 100 and the blood vessel wall 120La prior to the dilator main body 30, the guide wire is in a state where the proximal end side surface 36a of the dilator protrusion 36 is hooked on the strut 106. 110 can be pushed forward. At this time, since the stent graft 100 can receive the reaction force in the proximal direction acting on the dilator 14 when the guide wire 110 is advanced, the guide wire 110 can be smoothly moved without excessively increasing the hardness of the guide wire 110. You can move forward.

After the distal end of the sheath 12 is advanced to a predetermined position in the aneurysm 122 a, the dilator 14 is removed from the sheath 12, whereby the embolus 130 is inserted into the lumen 12 a of the sheath 12 larger than the lumen 14 a of the dilator 14. Through the aneurysm 122a.

Of the dilator protrusions 36, the base end side surface 36 a that faces the base end direction of the dilator 14 is a flat surface that extends in a direction orthogonal to the axis of the dilator main body 30. It is possible to efficiently transmit force between the two.

The pitch L3 of the dilator projection 36 and the pitch L1 of the sheath projection 20 are substantially the same. Therefore, in the transsealing, when the dilator main body 30 and the sheath main body 16 are advanced between the expanded stent graft 100 and the blood vessel wall 120La, the base end side surface 36a of the dilator projection 36 and the base end side surface 20a of the sheath projection 20 are connected. The plurality of struts 106 can be contacted efficiently.

The proximal end of the dilator projection 36 and the distal end of the sheath projection 20 have substantially the same circumferential phase. Therefore, the proximal end side surface 36 a of the dilator projection 36 and the proximal end side surface 20 a of the sheath projection 20 are connected to a plurality of struts 106. Can be contacted more efficiently.

Since the medical device 10 includes the rotation restricting portion 50 that restricts the relative rotation between the dilator 14 and the sheath 12, the dilator protrusion 36 and the sheath protrusion 20 can be prevented from being displaced from each other in the circumferential direction.

The dilator protrusion 36 extends to the tip of the tip protrusion 34. Thereby, in the transceiling, the distal end portion of the distal protrusion 34 can be smoothly inserted between the expanded stent graft 100 and the blood vessel wall 120La.

The outer peripheral surface 36 c of the dilator protrusion 36 is formed on the outer peripheral surface of the tip protrusion 34 by reducing the protrusion length of the tip of the dilator protrusion 36 relative to the outer periphery of the tip protrusion 34 toward one end in the spiral extending direction. It is connected smoothly. Thereby, in the transceiling, the distal end portion of the distal protrusion 34 can be smoothly inserted between the expanded stent graft 100 and the blood vessel wall 120La. It is possible to suppress an extra force from acting on the blood vessel wall 120La and the stent graft 100 when the dilator 14 rotates.

The present invention is not limited to the configuration described above. For example, at least one of the proximal end side surface 20a and the distal end side surface 20b of the sheath projection 20 may be a convex curved surface. In addition, at least one of the proximal end side surface 36a and the distal end side surface 36b of the dilator protrusion 36 may be a convex curved surface. In this case, damage to the blood vessel wall 120La by the sheath protrusion 20 and the dilator protrusion 36 can be suppressed.

Further, when the guide wire 110 having a spherical tip is used, the inner diameter of the tip of the dilator main body 30 (tip protruding portion 34) may be substantially the same as the diameter of the tip of the guide wire 110. In such a configuration, by positioning the distal end portion of the guide wire 110 at the distal end of the dilator body 30, the outer peripheral surface of the distal end protruding portion 34 is smoothly connected to the outer peripheral surface of the distal end portion of the guide wire 110. It is possible to suppress the occurrence of a step between the distal end of 34 and the distal end portion of the guide wire 110. Thereby, it is possible to prevent the blood vessel wall 120La from being damaged by the step between the tip of the dilator body 30 and the guide wire 110.

The direction of the spiral of the dilator protrusion 36 and the direction of the spiral of the sheath protrusion 20 may be opposite to each other.

The medical device 10 may include a catheter 11a shown in FIG. The catheter 11a has a flexible sheath 13 that is long and a dilator 14 that is removably inserted into the sheath 13. The dilator 14 includes a dilator main body 30 as a flexible long shaft main body that protrudes further to the front end side than the front end of the sheath main body 16 when inserted into the sheath 13, and the sheath main body 16 of the dilator main body 30. It has a dilator projection 36 as a shaft projection provided on the outer peripheral surface of the tip projection 34 that is located further on the tip side and that forms the tip shaft portion 17a and spirals around the dilator body 30 in the circumferential direction. The sheath 13 is configured in the same manner as the sheath 12 described above except that the sheath protrusion 20 is not provided. Even with such a configuration, the same effects as those of the dilator 14 described above can be obtained.

The expansion body is not limited to the stent graft 100 described above, and may be formed of, for example, a fine mesh strut and may not include the graft 102.

Claims

A medical device comprising a catheter (11, 11a) that can be placed between a blood vessel wall (120La) connected to an aneurysm (122a) and an expansion body (100) placed in a blood vessel connected to the aneurysm (122a) ( 10)
The catheter (11, 11a)
A flexible and long shaft body;
Provided on the outer peripheral surface of the tip shaft portion (17, 17a) constituting at least the tip portion of the shaft main body so as to contact the strut (106) constituting the expansion body (100), and the shaft main body in the circumferential direction A shaft projection that spirally circulates,
A medical device (10) characterized by the above.
The medical device (10) according to claim 1, comprising:
The catheter (11) has a sheath (12) including a sheath body (16) as the shaft body and a sheath protrusion (20) as the shaft protrusion,
The sheath protrusion (20) is provided to be positioned between the expansion body (100) and the blood vessel wall (120La) when delivering an embolus (130) into the aneurysm (122a). Yes,
A medical device (10) characterized by the above.
The medical device (10) according to claim 2, wherein
Of the sheath protrusions (20), the proximal end side surface (20a) oriented in the proximal end direction of the sheath (12) is a flat surface extending in a direction perpendicular to the axis of the sheath body (16), or A flat surface inclined toward the proximal end of the sheath body (16) toward the protruding end of the sheath projection (20);
A medical device (10) characterized by the above.
The medical device (10) according to claim 2 or 3,
The sheath projection (20) extends to the distal end of the distal shaft portion (17).
A medical device (10) characterized by the above.
The medical device (10) according to any one of claims 2 to 4,
In the outer peripheral surface (20c) of the sheath projection (20), the protruding length of the distal end portion of the sheath projection (20) with respect to the outer peripheral surface of the distal end shaft portion (17) decreases toward one end in the spiral extending direction. As a result, the end shaft portion (17) is smoothly connected to the outer peripheral surface.
A medical device (10) characterized by the above.
The medical device (10) according to any one of claims 2 to 5,
The catheter (11) includes a dilator (14) removably inserted into the sheath (12),
The dilator (14) is a long dilator body (30) having flexibility and protruding toward the distal end side of the distal end of the sheath body (16) in a state of being inserted into the sheath (12);
A dilator that is provided on the outer peripheral surface of the tip protrusion (34) located on the tip side of the sheath body (16) in the dilator body (30) and spirals around the dilator body (30) in the circumferential direction. A protrusion (36),
A medical device (10) characterized by the above.
The medical device (10) according to claim 6, wherein:
Of the dilator protrusion (36), the base end side surface (36a) oriented in the base end direction of the dilator (14) is a flat surface extending in a direction orthogonal to the axis of the dilator body (30), or A flat surface inclined toward the proximal end of the dilator body (30) toward the protruding end of the dilator protrusion (36);
A medical device (10) characterized by the above.
The medical device (10) according to claim 6 or 7,
The pitch (L3) of the dilator protrusion (36) and the pitch (L1) of the sheath protrusion (20) are substantially the same.
A medical device (10) characterized by the above.
The medical device (10) according to claim 8,
The proximal end of the dilator protrusion (36) and the distal end of the sheath protrusion (20) have substantially the same circumferential phase.
A medical device (10) characterized by the above.
The medical device (10) according to claim 9, wherein
A rotation restricting portion (50) for restricting relative rotation between the dilator (14) and the sheath (12);
A medical device (10) characterized by the above.
The medical device (10) according to any one of claims 6 to 10,
The dilator protrusion (36) extends to the tip of the tip protrusion (34).
A medical device (10) characterized by the above.
The medical device (10) according to any one of claims 6 to 11,
In the outer peripheral surface (36c) of the dilator protrusion (36), the protrusion length of the tip end portion of the dilator protrusion (36) with respect to the outer peripheral surface of the tip protrusion portion (34) decreases toward one end in the spiral extending direction. By this, it is smoothly connected to the outer peripheral surface of the tip protrusion (34).
A medical device (10) characterized by the above.
The medical device (10) according to claim 1, comprising:
The catheter (11a)
A flexible sheath (13) that is long and flexible;
A dilator (14) removably inserted into the sheath (13),
The dilator (14) is a dilator body (30) which is a long shaft body having flexibility and protrudes more distally than the distal end of the sheath (13) in a state of being inserted into the sheath (13). )When,
The dilator main body (30) is provided on the outer peripheral surface of the tip protruding portion (34) that is located on the tip side of the sheath (13) and constitutes the tip shaft portion (17a), and the dilator main body (30). A dilator protrusion (36) as the shaft protrusion that spirally circulates in the circumferential direction,
A medical device (10) characterized by the above.