JP2015202227A - filter device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filter device capable of reliably installing a filter at a desired position of a blood vessel.SOLUTION: A filter device 10 includes a catheter 11 having a lumen 20; a shaft 12 extending along the longitudinal direction of the catheter 11 in the lumen 20; a filter 13 capable of changing its state between an expanded state in which it is exposed on the tip side of the catheter 11 and extends outside the external form of the catheter 11 and a contracted state in which it elastically contracts from the expanded state, and can be accommodated in the lumen 20; a slide ring 23 provided on the tip side of the filter 13 which can rotate with the shaft 12 as an axis, and can move along the shaft 12; and a slide ring 24 provided on the base end side of the filter 13 which can rotate with the shaft 12 as an axis and the movement in the longitudinal direction with respect to the shaft 12 is regulated.

Description

  The present invention relates to a filter device having a filter installed in a blood vessel.

  In the carotid artery region, when plaque or a thrombus flows to the peripheral side during stent placement, there is a risk of cerebrovascular clogging and cerebral infarction. In order to prevent this, conventionally, a filter is known as one that captures blood flow from the stenosis portion to the distal side without blocking (see Patent Document 1).

JP 2007-117760 A

  For example, in the filter described in Patent Document 1, a proximal end slider and a distal end side slider are provided at the distal end and the proximal end of the filter, respectively, and the distal end side slider and the proximal end side slider are mutually independent of the guide wire. And is slidably inserted. In the guide wire, a stopper is provided between the distal end side slider and the proximal end side slider. The stopper can be brought into contact with the distal end side slider and the proximal end side slider. Thereby, the filter can move to the proximal end side of the guide wire until the distal end side slider contacts the stopper, and can move to the distal end side of the guide wire until the proximal end slider contacts the stopper.

  The filter is inserted into the blood vessel via the introducer catheter. The filter accommodated in the introduction catheter is in a state in which the distal end side slider and the proximal end side slider are separated from each other and contracted along the guide wire. When the filter is exposed from the introduction catheter, the distal end side slider and the proximal end side slider approach each other, and the elastically restored filter expands in the radial direction.

  For example, while confirming the position of the distal end side slider or the proximal end side slider with X-rays, the filter is inserted into the blood vessel and positioned at a desired position, and then the filter is exposed even if the filter is exposed from the introduction catheter. Since the filter can move to the distal end side or the proximal end side along the guide wire until the distal end side slider or the proximal end side slider comes into contact with the stopper, the position shift from the position confirmed by the X-rays to the distal end side or the proximal end side. May occur. For example, even if an attempt is made to install a filter on the upstream side immediately before the blood vessel branches, the filter may expand on the downstream side of the branch due to a positional shift.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a filter device capable of reliably installing a filter at a desired position of a blood vessel.

  (1) A filter device according to the present invention includes a catheter having an accommodating space therein, a wire extending along the longitudinal direction of the catheter in the accommodating space of the catheter, and exposed to the distal end side of the catheter. An expanded state that extends outward from the outer shape of the catheter, a filter that is elastically contracted from the expanded state and can be changed into a contracted state that can be accommodated in the accommodation space, and a distal end side of the filter A slider that is rotatable about the wire and is movable along the wire, and is provided on a proximal end side of the filter, is rotatable about the wire, and is relative to the wire. And a proximal end side fixed portion in which movement in the longitudinal direction is restricted.

  With the contracted filter housed in the catheter housing space, the catheter is inserted into the blood vessel until the tip of the catheter reaches the desired position of the blood vessel. When the distal end of the catheter reaches a desired position, the filter is exposed from the distal end of the catheter by pulling the catheter back to the proximal side with respect to the wire. The proximal end side of the filter is restricted from moving in the longitudinal direction with respect to the wire by the proximal end side fixing portion. Further, when the filter is elastically expanded from the contracted state, the slider approaches the proximal end side fixing portion. Since both the slider and the base end side fixing portion can rotate around the wire, the expanded filter rotates relative to the wire so as to follow the inner wall shape of the blood vessel.

  (2) Preferably, the filter device further includes a first stopper fixed to the wire between the slider and the proximal-side fixing portion.

  For example, when the wire rod is pushed to the distal end side, the base end side of the filter may be twisted, but when the slider comes into contact with the stopper, the slider comes closer to the base end side fixing portion and the filter bends. Too much or damage is suppressed.

  (3) Preferably, the proximal end side fixing portion includes a tubular body rotatably provided on the wire, and a second stopper fixed to the wire on the distal end side and the proximal end side from the tube body, It is what has.

  Thereby, a base end side fixing | fixed part is realizable with a simple structure.

  (4) Preferably, the filter has a conical shape having an opening on the proximal end side and reducing the diameter toward the distal end side.

  Thereby, the filter tends to be in an expanded state along the inner diameter and shape of the blood vessel.

  (5) Preferably, the slider and the base end side fixing portion are detectable by radiation.

  Thereby, the installation position of the filter in the blood vessel can be confirmed.

  According to the present invention, it is possible to reliably install a filter at a desired position of a blood vessel without causing positional displacement.

FIG. 1 is a diagram illustrating an external configuration of the filter device 10. FIG. 2 is a diagram illustrating a state in which the filter 13 is in a contracted state and the catheter 11 is inserted into the blood vessel 30. FIG. 3 is a diagram in which the filter 13 is expanded in the blood vessel 30.

  Hereinafter, preferred embodiments of the present invention will be described. In addition, this embodiment is only one embodiment of this invention, and it cannot be overemphasized that an embodiment can be changed in the range which does not change the summary of this invention.

  As shown in FIG. 1, the filter device 10 is provided on a catheter 11, a shaft 12 (an example of a wire) that extends along the longitudinal direction of the catheter in the catheter 11, and a distal end side of the shaft 12. A filter 13 and a tip guide 14 provided at the tip of the shaft 12 are provided. The filter device 10 is inserted into a blood vessel from the distal end side of the catheter 11, and the filter 13 is exposed from the distal end of the catheter 11, whereby the filter 13 is placed in an expanded state at a desired position of the blood vessel. . FIG. 1 shows the filter device 10 when the filter 13 is in the expanded state.

  The catheter 11 is a tube-shaped member that can be inserted into a target blood vessel, and has a lumen 20 (see FIGS. 2 and 3, an example of an accommodation space) that penetrates the distal end and the proximal end. The catheter 11 has flexibility so that it can bend along the curve or branch of the blood vessel. Examples of the catheter 11 include soft vinyl chloride resins, polyolefins such as polyethylene and polypropylene, ethylene-propylene copolymers and ethylene-vinyl acetate copolymers, polyolefin elastomers such as a mixture of polypropylene and polybutene, polyamides, PTFE, ETFE, and the like. Fluorine resin, polyamide elastomer, polyester elastomer, polyurethane elastomer, flexible synthetic resin tube such as fluororesin elastomer, rubber tube such as silicon rubber and latex rubber, etc. are preferably used. The outer diameter and length of the catheter 11 are appropriately set according to the target blood vessel and lesion position. Although not shown in each figure, a known configuration such as a handle portion for improving operability may be appropriately provided at the proximal end of the catheter 11.

  The shaft 12 is a wire extending along the longitudinal direction in the lumen 20 of the catheter 11. The shaft 12 has flexibility that can bend along a curve or branch of a blood vessel, and rigidity that does not bend the distal end when the proximal end is pushed in the longitudinal direction. As the shaft 12, a stainless steel wire, a piano wire, a high-tensile steel wire for a spring, a superelastic metal wire, or the like is preferably used. The outer diameter and length of the shaft 12 are appropriately set according to the position of the target blood vessel and lesion and the inner diameter and length of the catheter 11.

  The filter 13 is a conical mesh member having an opening 21 on the proximal end side and reducing the diameter toward the distal end side. The opening 21 has an annular shape having a larger diameter than the lumen 20 of the catheter 11. The opening 21 is on the base end side of the shaft 12 and faces in a direction inclined with respect to the axis (longitudinal direction) of the shaft 12. The front end of the filter 13 is closed and faces the front end side of the shaft 12. The filter 13 is flexible so as to be able to be accommodated in the lumen 20 of the catheter 11. The filter 13 can be accommodated in the lumen 20 of the catheter 11 when the filter 13 is bent (contracted). When the filter 13 goes out of the lumen 20, the filter 13 is elastically restored to have a conical shape (expanded state).

  The material of the filter 13 is preferably a superelastic alloy such as nickel-titanium steel wire, a high-strength steel wire for springs, a metal wire such as a piano wire, or a synthetic resin having relatively high rigidity such as polyamide or fluororesin. Used. The filter 13 is created by weaving a linear metal or the like. The size of the filter 13 and the annular diameter of the opening 21 are appropriately set according to the target blood vessel and the inner diameter of the catheter 11.

  The filter 13 is connected to the shaft 12 via slide rings 23 and 24 at the tip and the periphery of the opening 21. The slide rings 23 and 24 are ring-shaped members made of a member that can be detected by X-rays, such as stainless steel, and the shaft 12 is inserted into the internal space thereof. The filter 13 and the slide rings 23 and 24 are joined by welding or an adhesive. The slide ring 23 (an example of a slider) can rotate about the shaft 12 and can slide in the longitudinal direction with respect to the shaft 12. The tip of the filter 13 joined to the slide ring 23 can rotate around the shaft 12 together with the slide ring 23 and can slide in the longitudinal direction with respect to the shaft 12.

  The slide ring 24 (an example of a tubular body) is sandwiched between a pair of stoppers 25 and 26 (an example of a second stopper) fixed to the distal end side of the shaft 12. The stoppers 25 and 26 are ring-shaped members made of stainless steel or the like, and are fixed to the shaft 12 in a state where the shaft 12 is inserted into the internal space. The stoppers 25 and 26 do not rotate with respect to the shaft 12 and do not move in the longitudinal direction. The slide ring 24 sandwiched between the stoppers 25 and 26 is rotatable about the shaft 12 and is restricted from moving in the longitudinal direction with respect to the shaft 12. The periphery of the opening 21 of the filter 13 fixed to the slide ring 24 is rotatable about the shaft 12 and is restricted from moving in the longitudinal direction with respect to the shaft 12.

  Between the slide rings 23 and 24, the shaft 12 is provided with a stopper 27 (an example of a first stopper). The stopper 27 is a ring-shaped member made of stainless steel or the like, and is fixed to the shaft 12 in a state where the shaft 12 is inserted into the internal space. The stopper 27 does not rotate with respect to the shaft 12 and does not move in the longitudinal direction. The stopper 27 is disposed at a position where the slide ring 24 abuts or approaches a close distance in the filter 13 in the expanded state. The contact with the stopper 27 restricts the movement of the slide ring 23 from the position of the stopper 27 toward the slide ring 24.

  The tip guide 14 is fixed to the tip of the shaft 12. The tip guide 14 protrudes from the tip of the shaft 12 along the axis of the shaft 12. The distal end guide 14 includes a fitting portion 28 that fits on the distal end of the catheter 11 and a guide portion 29 that protrudes from the fitting portion 28. The fitting portion 28 is made of a synthetic resin, and a part of the catheter 12 enters the lumen 20 at the tip of the catheter 12, thereby fitting the catheter 11 with the tip of the lumen 20 sealed. The guide portion 29 is a stainless steel wire wound in a spiral shape, and is elastically curved along a curve or branch of a blood vessel.

[How to Use Filter Device 10]
Below, the usage method of the filter apparatus 10 is demonstrated, referring FIG. 2 and 3, only the outline of the filter 13 is shown.

  As shown in FIG. 2, the filter device 10 is inserted into the blood vessel 30 with the filter 13 contracted and accommodated in the lumen 20 of the catheter 11, with the distal end guide 14 fitted to the distal end of the catheter 11. . The filter device 10 is inserted into the blood vessel 30 from the distal guide 14 side, and the insertion method into the blood vessel 30 is the same as that of a general catheter. Whether or not the filter device 10 is inserted to a desired position of the blood vessel 30 is determined by confirming the positions of the slide rings 23 and 24 by X-ray irradiation.

  When the distal end side of the catheter 11, that is, the slide rings 23 and 24 reach a desired position of the blood vessel 30, the catheter 11 is pulled back toward the proximal end side with respect to the shaft 12 on the proximal end side of the filter device 10, that is, outside the body. The distal guide 14 is disengaged from the distal end of the catheter 11, and the catheter 11 is pulled back to the proximal end side, so that the contracted filter 13 is exposed to the outside from the distal end of the catheter 11. Note that the catheter 11 pulled back to the proximal end is completely pulled out of the body.

  The peripheral edge of the opening 21 that is the base end side of the filter 13 is restricted from moving in the longitudinal direction with respect to the shaft 12 by the slide ring 24 and the stoppers 25 and 26. The tip of the filter 13 can slide along the shaft 12 to the slide ring 24 side along with the slide ring 23, and the slide ring 23 slides toward the slide ring 24 together with the catheter 11 due to friction with the inner wall of the catheter 11. However, when the slide ring 23 comes into contact with the stopper 27, the filter 13 may be too bent or damaged by approaching the slide ring 24 more than the distance necessary for the slide ring 23 to be in the expanded state. Absent.

  As shown in FIG. 3, when the contracted filter 13 is exposed to the outside from the lumen 20 of the catheter 11, the filter 13 is elastically returned to an expanded state. When the filter 13 changes from the contracted state to the expanded state, the slide ring 23 slides along the shaft 12 until it contacts or approaches the stopper 27, but the slide ring 24 does not move in the longitudinal direction of the shaft 12. Therefore, the filter 13 is in an expanded state without moving from the position of the slide ring 24 confirmed by X-ray irradiation. Further, since both the slide rings 23 and 24 can rotate around the shaft 12, the expanded filter 13 rotates relative to the shaft 13 along the inner wall shape of the blood vessel 30.

  Although not shown in each drawing, after the filter 13 is placed in an expanded state at a desired position of the blood vessel 30, a balloon catheter or the like is inserted into the blood vessel 30 to expand or excise the stenosis (emboli). Made. Since the filter 13 is detained on the downstream side of the blood flow from the stenosis, the embolus separated from the stenosis by the treatment is captured by the filter 13.

  When the filter 13 is collected from the blood vessel 30, the reverse procedure is performed. That is, the catheter 11 is fed from the proximal end side of the shaft 12 to the distal end side, and the expanded filter 13 is accommodated in the lumen 20 of the catheter 11. When the distal end of the catheter 11 moves toward the distal end side in contact with the peripheral edge of the opening 12 of the filter 13, the filter 13 is elastically contracted corresponding to the lumen 20, and the filter 12 is contracted from the expanded state accordingly. Elastically changes to the state. In a state where the filter 13 is accommodated in the lumen 20, the filter device 10 is pulled out from the blood vessel 30.

[Operational effects of this embodiment]
According to the filter device 10 according to the present embodiment, the slide ring 23 provided on the distal end side of the filter 13 can rotate about the shaft 12 and can move along the shaft 12. The slide ring 24 provided on the proximal end side is rotatable about the shaft 12 and the movement in the longitudinal direction with respect to the shaft 12 is restricted, so that the filter 13 is placed at a desired position of the blood vessel 30. Even if the catheter 11 is pulled back to the proximal end side after being positioned, the filter 13 can be reliably installed at a desired position of the blood vessel 30 without causing the positional displacement of the filter 13.

  Further, since the stopper 27 is fixed to the shaft 12 between the slide rings 23 and 24, the base end side of the filter may be twisted when the shaft 12 is further pushed to the distal end side. Is in contact with the stopper 27, it is possible to prevent the filter 13 from being excessively bent or damaged by approaching a distance more than necessary for the slide ring 23 to be in the expanded state toward the slide ring 24.

[Modification]
In the embodiment described above, the stopper 27 is fixed to the shaft 12 between the slide rings 23 and 24. However, for example, when the filter 13 is made of a material that is difficult to bend or break, the stopper 27 is provided. It does not have to be.

  In the above-described embodiment, the slide ring 24 provided on the shaft 12 is sandwiched between the stoppers 25 and 26, so that the slide ring 24 can rotate about the shaft 12 and is Although the movement in the longitudinal direction is restricted, the proximal end side fixing portion according to the present invention may be realized by different configurations. For example, a part of the shaft 12 may be deformed into a convex shape so that the slide ring 24 cannot move in the longitudinal direction.

  In the above-described embodiment, the filter 13 has the opening 21 on the proximal end side and has a conical shape that closes by reducing the diameter toward the distal end side. However, the filter 13 has, for example, a dome shape. Or other shapes such as a hemispherical shape.

  In the above-described embodiment, the slide rings 23 and 24 can be detected by X-rays. Instead of the slide rings 23 and 24, the stoppers 25, 26, 27 and the tip guide 14 can be detected by X-rays. It may be configured.

  In the filter device 10 described above, the filter 13 may be formed of a flexible material, and a core material may be provided along the periphery of the opening 21 of the filter 13. This core material is elastically deformed so as to be accommodated in the lumen 20 of the catheter 11. The filter 13 can be accommodated in the lumen 20 of the catheter 11 in a state where the core material is elastically deformed and the filter 13 is bent (contracted state). When the filter 13 goes out of the lumen 20, the core material is elastically restored to become an annular shape, and accordingly, the entire shape of the filter 13 becomes a conical shape.

  The filter device 10 described above may be used not only in the carotid artery region but also in the coronary artery region and the shunt region.

10 filter device 11 catheter;
12 Shaft (Wire)
13 Filter 20 lumen (accommodating space)
23 Slide ring (slider)
24 Slide ring (tube body, proximal end fixing part)
25, 26 Stopper (second stopper, base end side fixing part)
27 Stopper (first stopper)

Claims (5)

A catheter having an accommodating space therein;
A wire extending along the longitudinal direction of the catheter in the accommodation space of the catheter;
An expanded state that is exposed to the distal end side of the catheter and spreads outward from the outer shape of the catheter, and a filter that is elastically contracted from the expanded state and can be changed into a contracted state that can be accommodated in the accommodating space;
A slider provided on the tip side of the filter, rotatable with the wire rod as an axis, and movable along the wire rod;
A filter device comprising: a base end side fixing portion which is provided on the base end side of the filter, is rotatable about the wire rod, and is restricted from moving in the longitudinal direction with respect to the wire rod; .   The filter device according to claim 1, further comprising a first stopper fixed to the wire between the slider and the proximal end side fixing portion. The proximal end fixing part is
A tubular body rotatably provided on the wire,
3. The filter device according to claim 1, further comprising a second stopper fixed to the wire at the distal end side and the proximal end side from the tube body.   The filter device according to any one of claims 1 to 3, wherein the filter has a conical shape having an opening on a proximal end side and having a diameter reduced toward a distal end side. The filter device according to any one of claims 1 to 4, wherein the slider and the base end side fixing portion are detectable by radiation.

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