JP4493608B2 - Atherectomy catheter - Google Patents

Description

  The present invention relates to an atherectomy catheter that removes an obstruction that narrows or occludes the lumen of a tubular organ.

  Generally, atherosclerosis is caused by the precipitation of fat within the patient's intimal layer. It is thought that a relatively soft thing is deposited at the beginning, and as time passes, a cholesterol component is taken in and develops into a calcified atheroma layer. Due to this developed atheroma layer, the blood vessel becomes stenotic or occluded, and blood flow is obstructed. If left untreated, it may cause angina or myocardial infarction in the case of the heart, necrosis of the hand and toe tissues due to ischemia in the case of the limbs, and intermittent claudication.

  Atherotomy is a procedure in which such a developed arteriosclerotic layer is excised from the blood vessel using a catheter. Usually, atherectomy is not performed alone and is used in combination with balloon angioplasty. Furthermore, in order to maintain the lumen formed by resection of the arteriosclerotic layer and balloon formation, a stent placement operation in which a stent is placed is performed. Even if such a procedure is performed, a new arteriosclerotic layer may develop inside the stent as pointed out by many research reports. In this case, atherectomy, balloon angioplasty, and stent placement are often performed again. Recently, studies have been made to reduce the stenosis rate by coating the stent with a drug expected to have an effect of preventing arteriosclerosis.

  Now, atherectomy may be performed for chronic occlusions where the blood flow is completely blocked in its indication. In some cases, the intima develops as the blood flow becomes very low. Various techniques have been published for such lesions.

  For example, the one described in Patent Document 1 has the expandability of the rotor itself, and uses the expandability of the sheath means as the rotor until the necessary inner diameter is secured in the blood vessel. The sheath means is pulled and pushed many times.

  On the other hand, another cause of clogging blood vessels is occlusion due to thrombus. The thrombosis may be caused by blood vessels bleeding for some reason, and the thrombosis may flow and accumulate in the periphery, but the surface of the atheroma layer is easily damaged. In some cases, platelets in the circulating blood collect and form a thrombus to occlude blood vessels, and some coexist with the atheroma layer. Balloon removal techniques have been used for many years to remove accumulated thrombus.

  By the way, in the catheter described in Patent Document 1, a basket-shaped sheath means (shearing) whose tip is closed against a narrowed or blocked lesion such as a lesion of the developed arteriosclerotic layer or a lesion with a thrombus. The operation | work which penetrates a member once is required. Further, it is necessary to repeat the pulling and pushing while rotating the sheath means until the inner diameter of the blood vessel is expanded to a necessary diameter.

  However, in the case of a lesion that is close to or occluded, the contrast agent is difficult to flow even under fluoroscopy, so it is difficult to determine where the lesion is approached, and a sheath means is attached to the lesion. It is difficult to pass accurately, and it is easy to damage the blood vessel and break through the blood vessel. As described above, the catheter described in Patent Document 1 has a drawback in that it requires not only a lot of time and labor but also a skill level for the work.

Special table 2004-503265 gazette

  An object of the present invention is to provide an atherectomy catheter capable of easily, quickly, reliably and safely removing an obstruction that narrows or occludes a lumen of a tubular organ.

Such an object is achieved by the present invention of the following (1) to ( 20 ).
(1) a flexible outer tube;
An inner tube that has flexibility and is inserted into the outer tube so as to be rotatable about the axis and movable in the axial direction with respect to the outer tube;
A removal member fixed to the distal end of the inner tube and housed in the outer tube to remove an obstruction that narrows or occludes the lumen of the tubular organ;
An atherectomy catheter that is attached to the inner tube and includes a flexible elongated guide member that serves as an axis when the inner tube rotates through the inner tube,
When removing the obstruction, the removal member protrudes from the distal end portion of the outer tube, and expands in the radial direction by its own elastic restoring force, and is in a deployed state in which the distal end is opened,
The guide member protrudes from the tip of the removal member,
The removal member is configured to be excavated by the distal end portion of the removal member by moving the removal member in the distal direction while rotating about the guide member via the inner pipe ,
The removal member has a plurality of substantially rhombus-shaped openings having a pair of corners in the axial direction on the side surface, has a thin, substantially cylindrical shape, and has a plurality of protrusions protruding in the tip direction at the tip portion. Part is provided along the circumferential direction,
When the removal member is housed in the outer tube and contracted, the opening portion has a pair of corners in the axial direction that have a small corner, and a pair in the direction substantially perpendicular to the axial direction. It has been deformed so that the corners of
When the removal member is in the expanded state, the opening portion is larger in the corners of the pair of corners in the axial direction than in the contracted state, and is substantially perpendicular to the axial direction. An atherectomy catheter, wherein corners of a pair of corners are smaller than in the contracted state .

(2) having a first flow path formed between the inner circumference of the outer pipe and the outer circumference of the inner pipe, and a second flow path formed at least partially in the lumen of the inner pipe The fluid containing the obstruction excavated by the removing member is discharged from the body through the first flow path, and the fluid can be injected into the tubular organ through the second flow path. Is composed of
Injecting / discharging means for discharging fluid through the first flow path, adjusting the flow rate of the fluid, injecting fluid through the second flow path, and adjusting the flow rate of the fluid atherectomy catheter according to the above (1) which are provided.

  (3) The atherectomy catheter according to (1) or (2), wherein the removing member has a plurality of openings on the side surface that occupy 4 to 97% of an area of the side surface in the deployed state.

  (4) The atherectomy catheter according to any one of (1) to (3), wherein the removing member has a net shape.

  (5) The atherectomy catheter according to any one of (1) to (4), wherein a tip of the removing member is separated from the guide member in the deployed state.

  (6) The atherectomy catheter according to any one of (1) to (5), wherein at least a part of the removal member is made of a shape memory alloy.

  (7) The atherectomy catheter according to any one of (1) to (6), further including first fixing means for fixing the axial movement of the inner tube with respect to the outer tube.

  (8) When the movement of the inner pipe in the axial direction is fixed, the first fixing means allows the outer pipe to rotate around the axis of the inner pipe, and the inner circumference of the outer pipe and the The atherectomy catheter according to (7) above, which has a function of blocking the passage of fluid in the first flow path formed between the outer periphery of the inner tube.

  (9) A connector having a port portion communicating with a first flow path formed between an inner periphery of the outer tube and an outer periphery of the inner tube is provided at a base end portion of the outer tube. The atherectomy catheter according to any one of 1) to (8).

(10) A connector having a port portion communicating with the first flow path formed between the inner periphery of the outer tube and the outer periphery of the inner tube is provided at the base end portion of the outer tube,
The atherectomy catheter according to (7) or (8), wherein the first fixing means is provided in the connector.

  (11) The first fixing unit includes a valve body installed inside a proximal end portion of the connector, and an operation unit that presses the valve body toward the inner tube or releases the press. The atherectomy catheter according to 10).

( 12 ) having a convex portion provided on the outer periphery of the distal end portion of the inner tube, and a tubular body into which the distal end portion of the inner tube is inserted,
The distal end portion of the inner tube is inserted into the tubular body so that the tubular body is located on the proximal side from the convex portion of the inner tube, and between the outer periphery of the inner tube and the inner periphery of the tubular body. The removal member is fixed to the inner tube by fixing the tubular body on the outer periphery of the inner tube in a state where the base end portion of the removal member is disposed on the inner tube. The atherectomy catheter according to any one of ( 11 ).

( 13 ) The atherectomy catheter according to any one of (1) to ( 12 ), further including second fixing means for fixing the guide member to the inner tube when the guide member is attached to the inner tube.

( 14 ) The second fixing means includes a hub provided at a proximal end portion of the inner tube, and a hub provided at a proximal end portion of the guide member and fitable with the hub of the inner tube. The atherectomy catheter according to ( 13 ) above.

( 15 ) The atherectomy catheter according to ( 14 ), wherein when the hub of the inner tube and the hub of the guide member are fitted, the distal end side of the guide member protrudes 1 to 8 mm from the distal end of the removal member.

( 16 ) The atherectomy catheter according to any one of ( 13 ) to ( 15 ), wherein a rotation assisting tool that rotates the inner tube and the removal member is connectable.

( 17 ) The atherectomy catheter according to any one of (1) to ( 16 ), wherein the guide member is made of any one of a superelastic alloy, stainless steel, and a resin.

( 18 ) At least the distal end portion of the guide member is made of an X-ray contrast member that is visible under X-ray fluoroscopy, or any of the above (1) to ( 17 ) in which an X-ray contrast portion is provided An atherectomy catheter according to the above.

( 19 ) Any one of the above (1) to ( 18 ), wherein a tapered portion whose outer diameter gradually decreases toward the distal end is provided at the distal end of the guide member, and the distal end of the tapered portion is rounded. The atherectomy catheter described in 1.

( 20 ) The outer tube includes an outer layer, an intermediate layer, and an inner layer, the intermediate layer functions as a reinforcing material, and the inner layer is made of a low-friction material (1) to ( 19 ). An atherectomy catheter according to any one of the above.

  According to the present invention, when removing the obstruction, since the removal member expands in the radial direction and the distal end is opened, the removal member rotates while moving forward, so that the tubular organ ( For example, an obstruction that narrows or occludes a lumen of a blood vessel or the like can be easily and quickly excavated and removed.

  Moreover, since the removal member rotates about the guide member, the removal member can be rotated easily, reliably and stably.

  For this reason, the obstruction can be easily, quickly, reliably and safely removed without damaging or breaking through the tubular organ and without requiring skill.

  Hereinafter, the atherectomy catheter of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

  In this embodiment, the case where the atherectomy catheter of the present invention is applied to a catheter for removing an obstruction that narrows or occludes the lumen of a blood vessel will be described.

  FIG. 1 is a side view showing an embodiment of the atherectomy catheter of the present invention, and FIG. 2 is a side view of the outer tube and connector of the atherectomy catheter shown in FIG. 3 is a cross-sectional view of the atherectomy catheter shown in FIG. 1. FIG. 3 (a) is a cross-sectional view taken along line AA in FIG. 1, and FIG. 3 (b) is a cross-sectional view in FIG. FIG. 3C is a cross-sectional view taken along the line CC in FIG. 1, and FIG. 3D is a cross-sectional view taken along the line DD in FIG. . 4 is a side view of the inner tube and the removal member of the atherectomy catheter shown in FIG. 1, FIG. 5 is a side view of the atherectomy catheter shown in FIG. 1 when the removal member is in the deployed state, and FIG. 5 is a side view showing the removal member side of the atherectomy catheter shown in FIG. 5, FIG. 7 is a side view showing the distal end side of the inner tube of the atherectomy catheter shown in FIG. 1, and FIG. 8 is the distal end of the inner tube shown in FIG. FIG. 9 is a sectional view of the connector and pusher of the atherectomy catheter shown in FIG. 1, and FIG. 10 is a side view of the guide member of the atherectomy catheter shown in FIG. FIG. 11 is a view showing a state in which the guide member in the atherectomy catheter shown in FIG. 12 is a diagram for explaining the operation of the atherectomy catheter shown in FIG. 5 (until the removal member removes the obstruction). FIG. 12 (a) shows that the removal member hits the obstruction. FIG. 12B is a diagram illustrating a state, FIG. 12B is a diagram illustrating a state where the removal member excavates and removes the obstruction, and FIG. 12C is a state where most of the obstruction is removed by the removal member. FIG.

  For convenience of explanation, in FIGS. 1, 2, and 4 to 12, the left side is referred to as “tip” and the right side is referred to as “base end”. Further, in FIG. 3, only the cross section is shown.

  The atherectomy catheter (catheter) 1 shown in these drawings is an unnecessary object generated in a blood vessel (tubular organ) such as an artery, that is, an unnecessary object for narrowing or blocking the lumen of the blood vessel (tubular organ). It is a medical device that secures blood flow by excavating (breaking) (crushing) and removing an obstruction (blood vessel obstruction) (performing blood vessel communication).

  As shown in FIG. 1, the atherectomy catheter 1 is rotatable about an axis and movable in the axial direction with respect to the outer tube 2, the connector 4 provided at the proximal end of the outer tube 2, and the outer tube 2. And excavating an inner tube 3 inserted into the outer tube 2 and an obstruction which is fixed (attached) to the distal end of the inner tube 3 and stored in the outer tube 2 to narrow or block the lumen of the blood vessel. And a guide member 6 that is attached to the inner tube 3 and serves as a shaft when the inner tube 3 rotates through the inner tube 3. Hereinafter, the atherectomy catheter is also simply referred to as “catheter”. In addition, the obstruction includes not only an unnecessary object that obstructs the lumen of the blood vessel but also various unnecessary objects that constrict the lumen even if the obstruction is not completely obstructed. Specifically, examples of the obstruction include a thrombus, a fatty spot, and an arteriosclerotic layer.

  As shown in FIGS. 1 and 2, the outer tube 2 has a cylindrical shape (cylindrical shape) with a constant diameter from the proximal end portion to the distal end portion. As shown in FIGS. 3 (a) and 3 (b), the outer tube 2 is composed of an inner layer 21, an intermediate layer 22 provided on the outer periphery thereof, and an outer layer 23 provided on the outer periphery thereof. It has a three-layer structure and is flexible so that it can bend freely along the bend of the blood vessel when inserted into the blood vessel.

  The dimensions of the outer tube 2 are not particularly limited. For example, the outer diameter (diameter) is about 1.5 to 3.5 mm, and the inner diameter (diameter) is about 1.0 to 3.0 mm. The length is preferably about 30 to 150 cm.

  The inner layer 21 of the outer tube 2 is preferably made of a low friction material. Examples of the constituent material of the inner layer 21 include a fluorine resin such as polytetrafluoroethylene.

  The intermediate layer 22 of the outer tube 2 is preferably configured to function as a reinforcing material. Examples of the constituent material of the intermediate layer 22 include stainless steel, tungsten, nickel, titanium, nickel / titanium alloy, nickel / cobalt alloy, nickel / manganese alloy, and carbon fiber. That is, the intermediate layer 22 is preferably composed of a mesh formed by braiding a predetermined wire such as the metal wire or carbon fiber.

  Examples of the constituent material of the outer layer 23 of the outer tube 2 include polyolefins such as polyethylene, polypropylene, and polybutadiene, polyvinyl chloride, polyurethane, polyether polyurethane, ethylene-vinyl acetate copolymer, polyethylene terephthalate, polybutylene terephthalate, Examples include various thermoplastic elastomers such as polyamide, polyether polyamide, polyester polyamide, styrene, polyolefin, polyurethane, polyester, polyamide, polybutadiene, trans polyisoprene, fluororubber, chlorinated polyethylene, etc. Further, a blend of two or more of these, or a laminate of two or more of these may be used.

  Such an outer tube 2 preferably enhances at least the X-ray contrast property of the distal end portion so as to be visible under fluoroscopy when removing the obstruction in the blood vessel. In this case, for example, an X-ray contrast unit composed of at least the constituent material of the outer layer 23, for example, an X-ray opaque material such as barium sulfate, platinum, gold, tungsten, or the like, or made of the X-ray opaque material. May be provided. In the present embodiment, as shown in FIGS. 1 and 2, an X-ray contrast unit (marker) 24 is provided at the distal end portion of the outer tube 2.

  As shown in FIGS. 3A and 3B, the inner tube 3 has a cylindrical shape (tubular shape) having an outer diameter that can be inserted through the outer tube 2, and the outer periphery of the inner tube 3. The first flow path X is formed between the inner periphery of the outer pipe 2 and the outer circumference. The inner tube 3 is also flexible like the outer tube 2.

  The constituent material of the inner tube 3 is, for example, polyester such as polyether ether ketone, polyethylene terephthalate, polybutylene terephthalate, fluorine such as polyimide, polyamide, polyether polyamide, polyester polyamide, ABS resin, AS resin, polytetrafluoroethylene, etc. In addition, a resin obtained by blending two or more of these, or a laminate of two or more of these may be used.

  The dimensions of the inner tube 3 are not particularly limited. For example, the outer diameter (diameter) is about 0.8 to 1.8 mm, the inner diameter (diameter) is about 0.5 to 1.5 mm, and the axial direction is axial. The length is preferably about 50 to 170 cm.

  As shown in FIG. 4, a removal member 5 for excavating and removing a blockage generated in the blood vessel is fixed to the distal end portion of the inner tube 3.

  As shown in FIG. 1, the removal member 5 is housed in the outer tube 2 and contracted (clogged) (stored state), and as shown in FIG. The unfolded state in which the tip is opened in the radial direction and its tip is opened can be taken by its own elastic restoring force. The removal member 5 is in a natural state when it is in an unfolded state, and at that time, the tip of the removal member 5 is separated from the guide member 6. When removing the obstruction, the removal member 5 protrudes from the distal end portion of the outer tube 2, and expands in the radial direction by its own elastic restoring force and is in a deployed state in which the distal end is opened.

Hereinafter, the removal member 5 in the unfolded state will be typically described.
As shown in FIGS. 4 and 5, the removal member 5 has a thin, substantially cylindrical shape (generally a mortar shape), and a plurality of protrusions 51 protruding in the distal direction extend along the circumferential direction at the distal end. Is provided. Thereby, an obstruction can be excavated easily and reliably.

  Further, the side wall portion of the removing member 5 has a net shape. That is, the removing member 5 has a plurality of openings 53 on the side surface (side wall portion). As a result, the obstruction excavated by the removing member 5 can be discharged through the opening 53, and a predetermined fluid can be injected into the blood vessel through the opening 53.

  The ratio of the opening 53 to the area of the side surface of the removing member 5 is preferably about 4 to 97%, and more preferably about 20 to 70%.

  If the ratio of the opening 53 is less than the lower limit value, the removal member 5 may not be able to self-expand depending on other conditions.

  Moreover, when the ratio which the opening part 53 accounts exceeds the said upper limit, depending on other conditions, the removal member 5 may change from the twisted state or the expanded state to the contracted state during excavation.

  The opening 53 has a substantially rhombus shape having a pair of corners in the axial direction. When the removing member 5 is housed in the outer tube 2 and contracted, the rhombus opening 53 is The corners of the pair of corners in the axial direction are reduced, and the corners of the other pair of corners (a pair of corners in a direction substantially perpendicular to the axial direction) are increased.

  And when the removal member 5 protrudes from the front-end | tip part of the outer tube | pipe 2, the opening part 53 of a rhombus will become larger than the time of the one pair of corner | angular part of an axial direction being in the said contracted state, and another pair of corners. The corner of the corner portion becomes smaller than that in the contracted state, and the removal member 5 expands in the radial direction and enters a deployed state in which the tip is opened (returns to the natural state).

  With such a configuration, the removing member 5 can be in a deployed state smoothly and reliably. Further, the protrusion 51 at the tip has a mountain shape (V shape).

  As a constituent material of the removing member 5, for example, a shape memory alloy or the like is preferably used. Examples of the shape memory alloy include Ti—Ni alloys such as Ti—Ni and Ti—Ni—Cu, Cu alloys such as Cu—Al—Mn and Cu—Al—Ni, and Fe—Mn—Si. Examples include Fe-based alloys, Au-Cd, Ag-Cd-based alloys, ferromagnetic shape memory alloys such as Ni-Mn-Ga, and Fe-Pd.

  Although the dimension of the removal member 5 is not specifically limited, The thickness is preferably about 0.1 to 0.3 mm, for example.

  The method of fixing (fixing) the removal member 5 to the distal end portion of the inner tube 3 is not particularly limited, and can be performed, for example, as follows.

  As shown in FIG. 7, an inner tube 3 having a ring-shaped convex portion 31 provided on the outer periphery of the distal end portion is prepared. In this case, for example, the photocurable resin can be applied to the outer periphery of the distal end portion of the inner tube 3, and the convex portion 31 can be formed by curing the photocurable resin.

  Moreover, the tubular body 55 shown in FIG. The inner diameter (diameter) of the tubular body 55 is set to a value equal to or less than a value obtained by adding a value twice the thickness of the removing member 5 to the outer diameter (diameter) of the convex portion 31. Moreover, as a constituent material of the tubular body 55, stainless steel etc. are mentioned, for example.

  As shown in FIG. 8, the proximal end portion of the removal member 5 is squeezed and inserted into the tubular body 55, and the inner tube 3 is placed on the proximal end side in the proximal end portion of the removal member 5 and the tubular body 55. The tubular body 55 is brought into contact with the convex portion 31 and stopped. The tubular body 55 is located on the proximal side from the convex portion 31 of the inner tube 3. As a result, the tubular body 55 is placed on the outer periphery on the proximal end side of the convex portion 31 of the inner tube 3, and the proximal end portion of the removing member 5 is disposed between the outer periphery of the inner tube 3 and the inner periphery of the tubular body 55. The

  Then, the base end of the removing member 5 is protruded from the base end of the tubular body 55 to the base end side by a predetermined length, and the tube 56 is covered on the base end portion. Examples of the constituent material of the tube 56 include various resin materials.

  Next, the photocurable resin 57 is supplied from the proximal end side of the tube 56 to be cured, and the end portion of the removing member 5 is fixed to the inner tube 3 together with the tubular body 55. Subsequently, the photocurable resin 57 is applied and cured so as to fill the step between the end of the tube 56 and the inner tube 3. Thus, the removal member 5 is fixed to the inner tube 3 by fixing the tubular body 55 on the outer periphery of the inner tube 3 with the photocurable resin 57 (adhesive).

  For example, the tubular body 55 may be crimped and the removal member 5 may be fixed (fixed) to the distal end portion of the inner tube 3.

  As shown in FIG. 4, a pipe 71 is put on the proximal end portion of the inner tube 3 as rotation assisting means. Thereby, the rotational torque transmission property of the proximal end portion of the inner tube 3 becomes larger than the rotational torque transmission property of the distal end portion, and the inner tube 3 and the removal member 5 are easily rotated around the axis in the outer tube 3. . Examples of the constituent material of the pipe 71 include various metal materials such as stainless steel.

  The rotation assisting means is not limited to the pipe 71, and may be realized by, for example, configuring the base end portion of the inner tube 3 with various metal materials such as stainless steel.

  An inner tube hub 72 is provided at the proximal end (base end portion) of the inner tube 3. The inner tube hub 72 is provided with a hole (not shown) along the axis, and a knob portion 73 formed in a flat shape so that it can be rotated with fingers on the side surface. On the side, a connecting portion 74 is provided.

  As shown in FIG. 2, the connector 4 provided at the proximal end portion of the outer tube 2 is a Y connector and has a port portion 4 </ b> A. The inner periphery of the connector 4 and the outer periphery of the inner tube 3 are A first flow path X (see FIGS. 3A and 3B) is formed therebetween. That is, the port portion 4A communicates with the first flow path X. The connector 4 is coupled to the proximal end portion of the outer tube 2 by tightening the fastening member 20.

  Further, as shown in FIG. 9, a ring-shaped valve element 41 is installed on the inner side of the base end portion of the connector 4, and a pusher (operation portion) 42 is provided on the base end side. It is provided so as to be movable in the axial direction.

  The valve body 41 has ribs 41 a formed along the inner periphery thereof, and is engaged so as not to move toward the distal end side of the connector 4 at a stepped portion 43 formed by expanding the diameter at the proximal end portion of the connector 4. It has been stopped.

  On the inner peripheral surface of the outer portion 42 a of the pusher 42, a female screw 42 b that is screwed with a male screw 43 a formed on the outer peripheral surface of the base end portion of the connector 4 is formed. In this case, when the pusher 42 is rotated in a predetermined direction (when rotated), the pusher 42 moves in the distal direction along the connector 4, whereby the proximal end portion of the connector 4 and the valve body 41 are moved. When the pusher 42 is pressed toward the inner tube 3 side and is rotated in the opposite direction to the above (when rotated), the pusher 42 moves in the proximal direction along the connector 4, thereby the connector 42. 4 and the pressure to the inner pipe 3 side of the valve body 41 are released.

  When the pusher 42 moves in the distal direction and the proximal end portion of the connector 4 and the valve body 41 are pressed toward the inner tube 3, the axial movement of the inner tube 3 is fixed (blocked) with respect to the outer tube 2. Is done. At this time, rotation around the axis of the inner tube 3 is allowed with respect to the outer tube 2, and the passage of the fluid in the first flow path X is blocked (sealed) by the valve body 41.

  Further, when the pusher 42 moves in the proximal direction and the pressing of the proximal end portion of the connector 4 and the valve body 41 toward the inner tube 3 side is released, the axial direction of the inner tube 3 with respect to the outer tube 2 is released. Movement is allowed.

  Therefore, the valve body 41 and the pusher 42 constitute the main part of the first fixing means.

  As shown in FIG. 10, the guide member 6 has a long shape having flexibility. That is, it is a linear body having flexibility. When removing the obstruction, the guide member 6 protrudes from the distal end portion of the removal member 5 by a predetermined length. When the guide member 6 hits against the obstruction, the position of the obstruction can be specified. Further, the inner tube 3 and the removal member 5 rotate by piercing the distal end of the guide member 6 into the center of the obstruction. By using the shaft at the time of doing, blurring of the rotating shaft of the removal member 5 can be suppressed, damage to the blood vessel wall can be prevented, and the obstruction can be reliably removed.

  Although the dimension of the guide member 6 is not specifically limited, It is preferable that the outer diameter is about 0.5-1.2 mm.

  Further, a tapered portion 62 whose outer diameter gradually decreases toward the distal end is provided at the distal end of the guide member 6, and the distal end of the tapered portion 62 is rounded. Safety is improved by rounding the tip of the tapered portion 62.

  Moreover, it is preferable that the guide member 6 enhances at least the X-ray contrast property of the distal end portion so that the guide member 6 is visible under X-ray fluoroscopy when removing the obstruction in the blood vessel. That is, it is preferable that at least the distal end portion of the guide member 6 is composed of an X-ray contrast member or is provided with an X-ray contrast portion (marker).

  Moreover, it is preferable that the guide member 6 is comprised with either of a superelastic alloy, stainless steel, and resin. That is, examples of the constituent material of the guide member 6 include nickel, titanium, nickel / titanium alloy, nickel / cobalt alloy, nickel / manganese alloy, stainless steel, carbon steel, and resin.

  A guide hub 63 is provided at the base end of the guide member 6. As shown in FIGS. 1 and 5, the guide member 6 is inserted into the inner tube 3, and the guide hub 63 is fitted into the connecting portion 74 of the inner tube hub 72 of the inner tube 3. It is attached to the tube 3 and fixed.

  Therefore, the guide hub 63 and the inner pipe hub 72 constitute the main part of the second fixing means.

  Further, in a state where the guide hub 63 and the connecting portion 74 of the inner tube hub 72 are fitted and the guide member 6 is attached to the inner tube 3, the distal end side of the guide member 6 has a predetermined length from the distal end of the removal member 5. , To protrude. The predetermined length is preferably about 1 to 8 mm, and more preferably about 2 to 5 mm.

  By setting the predetermined length within the above range, the inner tube 3 and the removing member 5 can function reliably as a shaft while maintaining safety.

  As shown in FIG. 3D, the guide hub 63 is formed with a lumen 64 that has a substantially semicircular cross-sectional shape and penetrates in the axial direction. When the guide hub 63 is fitted into the inner tube hub 72 of the inner tube 3, the lumen of the inner tube 3, the lumen of the inner tube hub 72, and the lumen 64 of the guide hub 63 communicate with each other. A flow path Y is formed.

A connecting portion 65 is provided at the base end portion of the guide hub 63.
Here, in the atherectomy catheter 1, a rotation assisting tool (not shown) that rotates the inner tube 3, the removing member 5, and the guide member 6 can be connected. The rotation assisting tool is configured to be connected to, for example, the connecting portion 65 of the guide hub 63.

  In addition, the fluid containing the obstruction excavated by the removing member 5 can be discharged out of the body through the first flow path X, and a predetermined amount is inserted into the blood vessel through the second flow path Y. It is comprised so that a fluid can be inject | poured.

  In this case, for example, a discharge portion of an injection / discharge device (injection / discharge means) (not shown) is connected to the port portion 4A of the connector 4, and an injection portion of the injection / discharge device is connected to the connecting portion 65 of the guide hub 63. .

  And by the action | operation (drive) of the discharge part of an injection | pouring / exhaust apparatus, the fluid containing the obstruction | occlusion excavated by the removal member 5 is attracted | sucked and discharged | emitted. At this time, the flow rate of the fluid can be adjusted, that is, the flow rate per unit time can be adjusted.

  A predetermined fluid is injected into the blood vessel by the operation (drive) of the injection part of the injection / discharge device. At this time, the flow rate of the fluid can be adjusted, that is, the flow rate per unit time can be adjusted.

Next, an operation (an example of a usage method) of the atherectomy catheter 1 will be described.
When the treatment for removing the obstruction in the blood vessel is performed, the inner tube 3 to which the removal member 5 is fixed is inserted into the outer tube 2 in advance, and the distal end of the outer tube 2 with the diameter of the removal member 5 reduced. It is stored inside the side. The inner tube 3 and the outer tube 2 are inserted to a target site in the blood vessel by a guide wire operation (not shown) through a sheath (not shown). The situation at that time is monitored by X-ray contrast or the like.

  When the inner tube 3 and the outer tube 2 reach the target site of the blood vessel, the guide wire is removed, and then the guide member 6 is inserted into the inner tube 3 from its tip, and the guide hub 63 is connected to the inner tube hub. 72. Thereby, the guide member 6 is fixed to the inner tube 3.

  Next, the pusher 42 of the connector 4 is rotated to loosen the valve body 41, and the inner tube 3 is pushed forward in this state. As a result, as shown in FIG. 11, the removal member 5 protrudes from the distal end portion of the outer tube 2, and expands in the radial direction by its own elastic restoring force and is in an expanded state in which the distal end is opened. Further, the guide member 6 protrudes from the distal end by the set length of the removal member 5, and the distal end portion of the guide member 6 contacts the obstruction (lesioned portion) H. Then, the pusher 42 of the connector 4 is rotated to tighten the valve body 41 inward, and the inner tube 3 is fixed to the outer tube 2 so as to be rotatable.

  Next, as shown in FIG. 12A, the entire atherectomy catheter 1 is moved in the distal direction, the guide member 6 is advanced, the distal end of the guide member 6 is pierced into the obstruction H in the blood vessel, and the inner tube 3 Is rotated about the guide member 6 as an axis. As a result, the removal member 5 moves in the distal direction while rotating around the guide member 6.

  As a result, as shown in FIG. 12B, as the guide member 6 enters the obstruction H, the protrusion 51 at the tip of the removal member 5 excavates the obstruction H.

Thus, by performing forward movement and rotation of the guide member 6 and the removal member 5, the removal member 5 can reliably remove the obstruction H as shown in FIG. In this case, even if the obstruction H is, for example, a hard atheroma such as a calcified lesion occurring in a blood vessel, it can be reliably excavated and removed.
The removed obstruction H is discharged to the outside through the first flow path X.

  As described above, according to the atherectomy catheter 1, the removal member 5 is moved to the lesioned part of the blood vessel, and the removal member 5 is rotated in a state where the removal member 5 hits the obstruction H in the blood vessel. However, if it is moved in the distal direction, the obstruction H can be gradually excavated and removed by the protrusion 51 of the removing member 5, so that a guide wire as in the prior art is once penetrated through the lesioned part and repeatedly before and after. The operation | work of moving becomes unnecessary and the obstruction | occlusion object H can be excavated and removed easily, quickly and reliably.

  Further, since the removing member 5 rotates around the guide member 6, the removing member 5 can be rotated easily, reliably and stably.

  For this reason, the obstruction | occlusion object H can be removed easily, rapidly, reliably and safely, without damaging or breaking through a blood vessel and without requiring skill.

  Moreover, since the excavated obstruction | occlusion object H is discharged | emitted outside via the 1st flow path X, safety | security is high.

  In addition, when removing the obstruction | occlusion object H, while occluding the obstruction | occlusion object H excavated from the 1st flow path X, physiological saline etc. can also be inject | poured from the 2nd flow path Y. In this way, it is possible to continue removing the obstruction H without causing the blood vessel to contract or deform due to a pressure difference generated by suction when the excavated obstruction H is discharged to the outside.

  As described above, by removing the obstruction H, the blood vessel can be communicated and blood flow can be secured, and the path of the next device can be created, the next treatment step (expansion with a balloon, a stent, etc.), etc. Can be easily performed.

  Although the atherectomy catheter of the present invention has been described based on the illustrated embodiment, the present invention is not limited to this, and the configuration of each part is replaced with an arbitrary configuration having the same function. be able to. In addition, any other component may be added to the present invention.

Moreover, the site | part (location) from which an obstruction is removed by the atherectomy catheter of this invention is not restricted to a blood vessel, In addition, a bile duct, a urethra, etc. are mentioned, for example.
Moreover, as an obstruction, a thrombus, a fatty spot, an arteriosclerosis layer, a calculus, etc. are mentioned, for example.

It is a side view which shows embodiment of the atherectomy catheter of this invention. It is a side view of the outer tube | pipe and connector of the outer tube | pipe and connector of the atherectomy catheter shown in FIG. It is sectional drawing of the atherectomy catheter shown in FIG. It is a side view of the inner tube | pipe and removal member of the atherectomy catheter shown in FIG. It is an atherectomy catheter shown in FIG. 1, Comprising: It is a side view when a removal member is an expansion | deployment state. It is a side view which shows the removal member side of the atherectomy catheter shown in FIG. It is a side view which shows the front-end | tip part side of the inner tube | pipe of the atherectomy catheter shown in FIG. It is a fragmentary sectional view which shows the state which fixed the removal member to the front-end | tip part of the inner tube shown in FIG. It is sectional drawing of the connector and pusher of the atherectomy catheter shown in FIG. It is a side view of the guide member of the atherectomy catheter shown in FIG. It is a figure which shows the state which abutted the obstruction | occlusion object in the guide member in the atherectomy catheter shown in FIG. It is a figure for demonstrating the effect | action (until a removal member removes an obstruction | occlusion object) of the atherectomy catheter shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Atherectomy catheter 2 Outer tube 20 Fastening member 21 Inner layer 22 Intermediate layer 23 Outer layer 24 X-ray contrast part 3 Inner tube 31 Convex part 4 Connector 41 Valve body 41a Rib 42 Pusher 42a Outer part 42b Female screw 43 Step part 43a Male screw 4A Port part 5 Removal member 51 Protrusion part 53 Opening part 55 Tubular body 56 Tube 57 Photocurable resin 6 Guide member 62 Tapered part 63 Guide hub 64 Lumen 65 Connection part 71 Pipe 72 Inner pipe hub 73 Knob part 74 Connection part 100 Blood vessel H Obstruction X First flow path Y Second flow path

Claims (20)

A flexible outer tube;
An inner tube that has flexibility and is inserted into the outer tube so as to be rotatable about the axis and movable in the axial direction with respect to the outer tube;
A removal member fixed to the distal end of the inner tube and housed in the outer tube to remove an obstruction that narrows or occludes the lumen of the tubular organ;
An atherectomy catheter that is attached to the inner tube and includes a flexible elongated guide member that serves as an axis when the inner tube rotates through the inner tube,
When removing the obstruction, the removal member protrudes from the distal end portion of the outer tube, and expands in the radial direction by its own elastic restoring force, and is in a deployed state in which the distal end is opened,
The guide member protrudes from the tip of the removal member,
The removal member is configured to be excavated by the distal end portion of the removal member by moving the removal member in the distal direction while rotating about the guide member via the inner pipe ,
The removal member has a plurality of substantially rhombus-shaped openings having a pair of corners in the axial direction on the side surface, has a thin, substantially cylindrical shape, and has a plurality of protrusions protruding in the tip direction at the tip portion. Part is provided along the circumferential direction,
When the removal member is housed in the outer tube and contracted, the opening portion has a pair of corners in the axial direction that have a small angle, and a pair in a direction substantially perpendicular to the axial direction. It has been deformed so that the corners of
When the removal member is in the unfolded state, the opening is larger than that in the contracted state in which the corners of the pair of corners in the axial direction are substantially perpendicular to the axial direction. An atherectomy catheter, wherein corners of a pair of corners are smaller than in the contracted state . A first flow path formed between an inner circumference of the outer pipe and an outer circumference of the inner pipe, and a second flow path formed at least in part by a lumen of the inner pipe, The fluid including the obstruction excavated by the removing member is discharged from the body through one flow path, and the fluid can be injected into the tubular organ through the second flow path. And
Injecting / discharging means for discharging fluid through the first flow path, adjusting the flow rate of the fluid, injecting fluid through the second flow path, and adjusting the flow rate of the fluid The atherectomy catheter according to claim 1 provided .   The atherectomy catheter according to claim 1 or 2, wherein the removal member has a plurality of openings on the side surface that occupy 4 to 97% of the area of the side surface in the deployed state.   The atherectomy catheter according to any one of claims 1 to 3, wherein the removing member has a mesh shape.   The atherectomy catheter according to any one of claims 1 to 4, wherein a tip of the removal member is separated from the guide member in the deployed state.   The atherectomy catheter according to claim 1, wherein at least a part of the removal member is made of a shape memory alloy.   The atherectomy catheter according to any one of claims 1 to 6, further comprising first fixing means for fixing the axial movement of the inner tube with respect to the outer tube.   When the axial movement of the inner pipe is fixed, the first fixing means allows the outer pipe to rotate around the axis of the inner pipe, and the inner circumference of the outer pipe and the inner pipe The atherectomy catheter of Claim 7 which has a function which interrupts | blocks passage of the fluid of the 1st flow path formed between outer periphery.   The connector which has a port part connected to the 1st flow path formed between the inner periphery of this outer tube and the outer periphery of the said inner tube is provided in the base end part of the said outer tube. An atherectomy catheter according to any one of the above. A connector having a port portion communicating with a first flow path formed between an inner periphery of the outer tube and an outer periphery of the inner tube is provided at a base end portion of the outer tube,
The atherectomy catheter according to claim 7 or 8, wherein the first fixing means is provided in the connector.   The said 1st fixing means has the valve body installed in the inner side of the base end part of the said connector, and the operation part which presses the said valve body to the said inner tube side, or cancels the press. Atherectomy catheter. A convex portion provided on the outer periphery of the distal end portion of the inner tube, and a tubular body into which the distal end portion of the inner tube is inserted,
The distal end portion of the inner tube is inserted into the tubular body so that the tubular body is located on the proximal side from the convex portion of the inner tube, and between the outer periphery of the inner tube and the inner periphery of the tubular body. The removal member is fixed to the inner tube by fixing the tubular body on the outer periphery of the inner tube in a state where the base end portion of the removal member is disposed on the inner tube. An atherectomy catheter according to any one of the above.   The atherectomy catheter according to any one of claims 1 to 12, further comprising second fixing means for fixing the guide member to the inner tube when the guide member is attached to the inner tube.   The second fixing means includes a hub provided at a proximal end portion of the inner tube, and a hub provided at a proximal end portion of the guide member and fitable with the hub of the inner tube. The atherectomy catheter described in 1.   The atherectomy catheter according to claim 14, wherein when the hub of the inner tube and the hub of the guide member are fitted, the distal end side of the guide member protrudes 1 to 8 mm from the distal end of the removal member.   The atherectomy catheter according to any one of claims 13 to 15, wherein a rotation assisting tool for rotating the inner tube and the removal member is connectable.   The atherectomy catheter according to any one of claims 1 to 16, wherein the guide member is made of any one of a superelastic alloy, stainless steel, and a resin.   18. The atherectomy catheter according to claim 1, wherein at least a distal end portion of the guide member is formed of an X-ray contrast member that is visible under X-ray fluoroscopy, or is provided with an X-ray contrast portion. .   The atherectomy catheter according to any one of claims 1 to 18, wherein a tapered portion having an outer diameter gradually decreasing toward the distal end is provided at a distal end portion of the guide member, and the distal end of the tapered portion is rounded.   The said outer pipe | tube has an outer layer, an intermediate | middle layer, and an inner layer, The said intermediate | middle layer functions as a reinforcing material, The said inner layer is comprised by the low friction material. Atherectomy catheter.

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