JP2019050991A - Medical device - Google Patents

Abstract

To provide a medical device capable of cutting an object, which can improve safety.SOLUTION: A medical device 10 inserted into a living body lumen for cutting an object in the living body lumen includes: a long cylindrical member 20 that is rotatably driven; a slide member 30, which is a tube body arranged inside the cylindrical member 20 so as to be slidable in an axial direction, and which extends on a distal side as compared with the cylindrical member 20; and at least one linear member 41, whose distal end is connected to the slide member 30 and proximal end is connected to the cylindrical member 20. The linear member 41 bend when the slide member 30 slides in the axial direction with respect to the cylindrical member 20.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a medical device capable of cutting an object in a living body lumen.

  A debulking device that removes the object to be removed may be used to remove the calcified lesion in the coronary artery. A rotablator is known as a debulking device (see, for example, Patent Document 1).

  The rotablator includes a rotatable drill having abrasive grains on the outer peripheral surface. When cutting a calcified lesion with a rotablator, the drill is reciprocated with a weak force in the axial direction in the blood vessel in order to maximize the effect of removing the calcified lesion and minimize the influence on the healthy blood vessel.

Special table 2003-504090 gazette

  However, when the guide wire that guides the rotablator is bent sharply, when the rotabulator is moved along the guide wire, the drill may come into strong contact with the blood vessel. In this case, there is a possibility that the blood vessel is shaved by the drill that makes strong contact, and the blood vessel is perforated.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a cutable medical device that can improve safety.

  A medical device that achieves the above object is a medical device that is inserted into a living body lumen to cut an object in the living body lumen, and includes a long cylindrical member that is rotationally driven, A tubular body that is slidably disposed in the axial direction inside or outside, a sliding member that extends to the distal side of the cylindrical member, and a distal end connected to the sliding member, And at least one linear member connected to the cylindrical member, and the linear member bends when the sliding member slides in the axial direction with respect to the cylindrical member. .

  In the medical device configured as described above, a strong force acts on the sliding member or the linear member from the distal side, so that the sliding member moves to the proximal side with respect to the cylindrical member. Thereby, a linear member bends and spreads to the radial direction outer side of a cylindrical member and a sliding member. For this reason, the contact area of the linear member with respect to the living body lumen increases, and the force acting on the living body lumen from the linear member is dispersed. Therefore, it is possible to improve safety by suppressing damage to the living body lumen.

  The sliding member may rotate in conjunction with rotation around the axis of the cylindrical member. Thereby, the rotational force which rotates a linear member can be made to act not only from a cylindrical member but from a sliding member. For this reason, the force which acts on a contact object from a linear member can be improved, and the object of a biological lumen can be effectively cut with a linear member.

  The sliding member and the cylindrical member are provided with a sliding protrusion protruding to limit relative rotation around the axis and a sliding groove into which the sliding protrusion is slidably fitted in the axial direction. You may have. Thereby, the sliding member rotates in conjunction with the rotation around the axis of the cylindrical member.

  The linear member may have a plurality of convex portions on the surface. Thereby, the object of a biological lumen can be shaved with the rotating linear member.

  The linear member may have a protruding portion that bends and protrudes inward in the radial direction of the cylindrical member or the sliding member. Thereby, a linear member is easy to bend at a projection part. Therefore, the medical device can have a structure in which the cutting portion is easily spread outward in the radial direction while the wire diameter of the linear member is set to a thickness capable of obtaining an appropriate cutting ability. For this reason, the medical device can obtain high safety while maintaining high cutting ability.

  The said linear member may be arrange | positioned at the spiral which winds the axial center of the said cylindrical member. Thereby, when a linear member rotates and contacts a contact object, it becomes difficult to fall rather than the structure extended only to an axial direction. For this reason, the cutting ability of a linear member improves.

  The cylindrical member has a first restricting convex portion protruding inward or outward in the radial direction, and the sliding member moves in a distal direction with respect to the cylindrical member. In this case, the first restricting convex portion may have a second restricting convex portion. Thereby, the magnitude | size of a cutting part can be limited to a predetermined range, and it can suppress that the outer diameter of a cutting part becomes small too much. Furthermore, it is possible to prevent the sliding member from dropping from the cylindrical member 120.

It is a side view which shows the medical device which concerns on 1st Embodiment. It is a figure which shows the distal part of the medical device which concerns on 1st Embodiment, (A) is a side view, (B) is the front view seen from the arrow A of (A). It is a side view showing the state where the cutting part of the medical device concerning a 1st embodiment changed. It is sectional drawing which shows the medical device inserted in the blood vessel. It is a side view which shows the distal part of the medical device which concerns on 2nd Embodiment. It is a side view which shows the state which deform | transformed the distal part of the medical device which concerns on 2nd Embodiment. It is a side view which shows the distal part of the medical device which concerns on 3rd Embodiment. It is a side view which shows the distal part of the medical device which concerns on 4th Embodiment. It is a figure which shows the cylindrical member and sliding member of the medical device which concern on 5th Embodiment, (A) is sectional drawing, (B) is sectional drawing which follows the BB line of (A). It is sectional drawing which shows the state which moved the sliding member of the medical device which concerns on 5th Embodiment to the proximal side.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the dimension ratio of drawing is exaggerated on account of description, and may differ from an actual ratio.

<First Embodiment>
The medical device 10 according to the first embodiment is a debulking device that is inserted into an artery and cuts and removes a calcified lesion. In this specification, the side inserted into the blood vessel of the device is referred to as “distal side”, and the proximal side for operation is referred to as “proximal side”. Further, the longitudinal direction of the medical device 10 is referred to as an axial direction.

  As shown in FIGS. 1 and 2, the medical device 10 includes a cylindrical member 20, a sliding member 30 that slides with respect to the cylindrical member 20, and a cutting portion 40 for cutting a lesioned portion. . The medical device 10 further includes a drive shaft 50 that rotates the cylindrical member 20, an outer sheath 60 that rotatably accommodates the drive shaft 50, and a rotation drive unit 70 that rotates the drive shaft 50.

  The rotation drive unit 70 includes a drive source 71 (for example, a motor) that rotates the drive shaft 50. A proximal opening 72 that communicates with the inner shafts of the drive shaft 50, the cylindrical member 20, and the sliding member 30 is formed in the proximal portion of the rotation drive unit 70. The lumens of the drive shaft 50, the cylindrical member 20, and the sliding member 30 are a guide wire lumen 11 into which a guide wire can be inserted.

  The outer sheath 60 is coaxially disposed outside the drive shaft 50 extending distally from the rotary drive unit 70. A proximal portion of the outer sheath 60 is connected to the rotation driving unit 70. The outer sheath 60 accommodates the drive shaft 50 in a rotatable manner.

  The cylindrical member 20 is a cylindrical member. The proximal portion of the tubular member 20 is coaxially connected to the drive shaft 50 at the distal portion of the drive shaft 50. For this reason, the cylindrical member 20 rotates together with the drive shaft 50. The distal end 21 of the tubular member 20 is located more distally than the distal end of the outer sheath 60. The distal end 21 of the cylindrical member 20 is located in the vicinity of the cutting part 40.

  As shown in FIGS. 2 and 3, the sliding member 30 is a cylindrical member that can slide inside the cylindrical member 20 in the axial direction. The proximal portion of the sliding member 30 is located inside the tubular member 20, and the distal portion of the sliding member 30 is located more distally than the distal end 21 of the tubular member 20.

  The constituent material of the cylindrical member 20 and the sliding member 30 is preferably a material having relatively high rigidity. For example, it is preferable to use a metal such as Ni—Ti, brass, SUS, or aluminum. In addition, as long as it is a material with comparatively high rigidity, the constituent material of the cylindrical member 20 and the sliding member 30 is not specifically limited to a metal, For example, resin, such as a polyimide, a vinyl chloride, a polycarbonate, may be sufficient.

  The cutting part 40 is being fixed to the cylindrical member 20 and the sliding member 30 as shown in FIG. The cutting unit 40 includes a plurality (eight in the present embodiment) of linear members 41. In addition, the number of the linear members 41 is not specifically limited. Moreover, although the cross-sectional shape of the linear member 41 is substantially circular, it may not be substantially circular. The proximal end portion of each linear member 41 is fixed to the tubular member 20 by a proximal fixing portion 42. The proximal side fixing portion 42 is an annular member fixed to the outer peripheral surface on the proximal side of the distal end 21 of the cylindrical member 20. The proximal-side fixing portion 42 fixes the proximal ends of all the linear members 41 in a state where the proximal ends are arranged on the outer peripheral surface of the tubular member 20 in the circumferential direction. The distal side fixing portion 43 is an annular member fixed to the outer peripheral surface of the sliding member 30 on the distal side of the distal end 21. The distal side fixing portion 43 fixes the distal ends of all the linear members 41 in a state where they are arranged on the outer peripheral surface of the sliding member 30 in the circumferential direction. The means for fixing the linear member 41 to the tubular member 20 or the sliding member 30 is not particularly limited, and may be fixed by, for example, welding or an adhesive.

  Each linear member 41 is curved such that a substantially central portion in the axial direction is separated from the tubular member 20 in the radial direction. As a result, the substantially central portion of each linear member 41 in the axial direction is arranged in the circumferential direction at a position away from the tubular member 20 in the radial direction. For this reason, the cutting part 40 has a uniform bulge in the circumferential direction as a whole. Each linear member 41 is shaped in advance by heat treatment into the above-described curved shape. In addition, each linear member 41 does not necessarily need to be previously shaped into a curved shape. When the sliding member 30 moves proximally with respect to the tubular member 20, the distal side fixing portion 43 approaches the proximal side fixing portion 42 as shown in FIG. 3. Thereby, each linear member 41 is further curved so that the substantially central portion in the axial direction is separated from the tubular member 20 in the radial direction.

  Each linear member 41 has a large number of convex portions 44 on the outer surface on the distal side of the substantially central portion in the axial direction. The convex portion 44 is formed by adhering diamond particles, for example. In addition, the convex part 44 may be formed when a part of particle | grains contained in the material of the linear member 41 protrude from an outer surface.

  The constituent material of the linear member 41 is not particularly limited, but it is preferable that the linear member 41 can be elastically deformed greatly, and it is desirable that the linear member 41 is made of a material having shape memory properties. As a constituent material of the linear member 41, for example, a shape memory alloy, stainless steel, or the like to which a shape memory effect or superelasticity is imparted by heat treatment is preferable. As the shape memory alloy, a Ni-Ti system, a Cu-Al-Ni system, a Cu-Zn-Al system, or a combination thereof is suitable.

  Next, the operation of the medical device 10 according to the first embodiment will be described by taking as an example the case of cutting a calcified lesion in an artery.

  As shown in FIG. 4, the medical device 10 of the present embodiment is pushed into the vicinity of the lesioned part L in a state where the guide wire 80 is inserted into the guide wire lumen 11. In this state, when the drive shaft 50 is rotated by the rotation drive unit 70, the cutting unit 40 is rotated accordingly. When the cutting part 40 is moved in the blood vessel in this state, the convex part 44 of the cutting part 40 contacts the lesioned part L, and the convex part 44 cuts the lesioned part L.

  When the guide wire 80 is bent sharply, when the medical device 10 moves to the distal side along the guide wire 80, a force toward the proximal side acts on the distal portion of the sliding member 30 or the cutting portion 40. To do. 3 and 4, the sliding member 30 moves proximally with respect to the tubular member 20, and the distal side fixing portion 43 approaches the proximal side fixing portion 42. When the distal side fixing portion 43 approaches the proximal side fixing portion 42, the linear member 41 is elastically deformed. As a result, the outer diameter of the cutting portion 40 increases, and the inclination angle θ of the distal portion of the cutting portion 40 with respect to the axial center of the sliding member 30 increases. For this reason, the contact area with respect to the blood vessel of the cutting part 40 becomes large. Therefore, the force acting on the blood vessel from the cutting portion 40 is dispersed over a wide area, and the occurrence of damage such as blood vessel perforation can be suppressed. When the sliding member 30 or the cutting unit 40 is separated from the blood vessel, the cutting unit 40 can return to the original shape by its own elastic force.

  As described above, the medical device 10 according to the first embodiment is a device that is inserted into a living body lumen and cuts an object in the living body lumen, and is a long cylindrical member 20 that is rotationally driven. And a sliding member 30 that is slidably disposed in the axial direction inside the cylindrical member 20, a sliding member 30 that extends to the distal side of the cylindrical member 20, and a distal end that is a sliding member 30, and at least one linear member 41 whose proximal end is connected to the cylindrical member 20. The sliding member 30 slides in the axial direction with respect to the cylindrical member 20. The linear member 41 is bent.

  In the medical device 10 configured as described above, a strong force acts on the sliding member 30 from the distal side, so that the sliding member 30 moves to the proximal side with respect to the tubular member 20. Thereby, the linear member 41 bends and spreads radially outward of the tubular member 20 and the sliding member 30. For this reason, the contact area of the linear member 41 with respect to the living body lumen increases, and the force acting on the living body lumen from the linear member 41 is dispersed. Therefore, it is possible to improve safety by suppressing damage such as perforation of a living body lumen.

The linear member 41 has a plurality of convex portions 44 on the surface. Thereby, the object of the living body lumen can be shaved by the rotating linear member 41.
Second Embodiment

  As shown in FIG. 5, the medical device according to the second embodiment is different from the medical device 10 according to the first embodiment only in the cutting unit 90. In addition, the same code | symbol is attached | subjected to the site | part which has a function similar to 1st Embodiment, and description is abbreviate | omitted.

  The cutting unit 90 includes a plurality of linear members 91. Each linear member 91 has a protruding portion 92 that bends in a U-shape at a substantially central portion in the axial direction. The protruding portion 92 is bent and protrudes inward in the radial direction of the tubular member 20 and the sliding member 30.

  The linear member 91 is required to have a certain thickness in order to increase the cutting ability. Normally, a wire becomes difficult to bend if it is thick, but if there is a protruding portion 92 that is bent inward in the radial direction, the linear member 91 is easily bent outward in the radial direction. For this reason, when the force toward the proximal side acts on the distal portion of the sliding member 30 or the cutting portion 90, the protruding portion 92 is deformed so that the U-shaped end portions 93 approach each other as shown in FIG. In addition, the outer diameter of the cutting portion 90 is increased. For this reason, the contact area with respect to the vascular wall of the linear member 91 becomes large, and the force which acts on the vascular wall from the linear member 91 is disperse | distributed. And since the protrusion part 92 protrudes toward the inner side of radial direction, it is hard to contact a blood vessel wall. Therefore, it is possible to improve safety by suppressing damage such as perforation of blood vessels. Therefore, the medical device according to the second embodiment can obtain high safety while setting the wire diameter of the linear member 91 to a thickness capable of obtaining an appropriate cutting ability. In addition, the cross-sectional shape of the wire of the site | part in which the protrusion part 92 of the linear member 91 is formed may differ from the cross-sectional shape of another site | part. For example, the shape of the wire at the portion where the protruding portion 92 of the linear member 91 is formed may be a flat plate shape, that is, the cross-sectional shape of the wire may be substantially rectangular. Thereby, the protrusion 92 can be more easily bent. Further, the linear member 91 may have a flat plate shape over the entire length.

In addition, although the position where the protrusion part 92 of the linear member 91 is formed is a substantially central part in the axial direction, it may not be a substantially central part.
<Third Embodiment>

  As shown in FIG. 7, the medical device according to the third embodiment is different from the medical device 10 according to the first embodiment only in the cutting unit 100. In addition, the same code | symbol is attached | subjected to the site | part which has a function similar to 1st Embodiment, and description is abbreviate | omitted.

  The cutting unit 100 includes a plurality of linear members 101. Each linear member 101 has a protruding portion 102 wound in a coil shape at a substantially central portion in the axial direction. The protruding portion 102 is bent and protrudes inward in the radial direction of the cylindrical member 20 and the sliding member 30. The number of windings of the protrusion 102 is one in this embodiment, but may be two or more.

When the coil-shaped protrusion 102 is present, the linear member 101 is easily bent outward in the radial direction. For this reason, when the force which goes to the proximal side acts on the distal part of the sliding member 30 or the cutting part 100, the coil-shaped protrusion part 102 will bend and the outer diameter of the cutting part 100 will become large. For this reason, the contact area with respect to the blood vessel wall of the linear member 101 becomes large, and the force which acts on the blood vessel wall from the linear member 101 is dispersed. And since the protrusion part 102 protrudes toward the inner side of radial direction, it is hard to contact a blood vessel wall. Therefore, it is possible to improve safety by suppressing damage such as perforation of blood vessels. Therefore, the medical device according to the third embodiment can obtain high safety while setting the wire diameter of the linear member 101 to a thickness that can obtain an appropriate cutting ability.
<Fourth embodiment>

  As shown in FIG. 8, the medical device according to the fourth embodiment is different from the medical device 10 according to the first embodiment only in the cutting unit 110. In addition, the same code | symbol is attached | subjected to the site | part which has a function similar to 1st Embodiment, and description is abbreviate | omitted.

The cutting unit 110 includes a plurality of linear members 111. Each linear member 111 is spirally arranged so as to wind the axial center of the cylindrical member 20 and the sliding member 30. The spiral linear member 111 extends not only in the axial direction but also in the circumferential direction of the tubular member 20 and the sliding member 30. For this reason, when the helical linear member 111 rotates and comes into contact with the object to be cut, the helical linear member 111 is less likely to fall than a structure extending only in the axial direction and is not easily deformed. For this reason, the medical device according to the fourth embodiment improves the cutting ability of the linear member 111. When a force toward the proximal side acts on the sliding member 30 or the distal portion of the cutting portion 110, the outer diameter of the cutting portion 110 increases. For this reason, the contact area with respect to the blood vessel wall of the linear member 111 becomes large, and the force which acts on the blood vessel wall from the linear member 111 is disperse | distributed. Therefore, it is possible to improve safety by suppressing damage such as perforation of blood vessels.
<Fifth Embodiment>

  As shown in FIGS. 9 and 10, the medical device according to the fifth embodiment is different from the medical device 10 according to the first embodiment only in the cylindrical member 120 and the sliding member 130. In addition, the same code | symbol is attached | subjected to the site | part which has a function similar to 1st Embodiment, and description is abbreviate | omitted.

  The cylindrical member 120 has two sliding grooves 121 extending in the axial direction on the inner wall surface of the distal portion. The two sliding grooves 121 are arranged at positions facing each other in the circumferential direction. The cylindrical member 120 has a first restricting convex portion 122 that protrudes inward in the radial direction so that the groove is interrupted at the distal end of the sliding groove 121.

  The sliding member 130 has two sliding convex portions 131 protruding outward in the radial direction on the outer peripheral surface of the proximal portion. The two sliding protrusions 131 are arranged at positions facing each other in the circumferential direction. The sliding protrusion 131 is fitted to the sliding groove 121 so as to be slidable in the axial direction. The sliding protrusion 131 can move along the sliding groove 121 without departing from the sliding groove 121. For this reason, the sliding member 30 is movable in the axial direction with respect to the cylindrical member 120, and the rotation around the axial center with respect to the cylindrical member 120 is limited. Accordingly, the sliding member 130 rotates in conjunction with the rotation around the axial center of the cylindrical member 120 that is rotationally driven by the drive shaft 50. Thereby, the rotational force that rotates the linear member 41 acts not only from the cylindrical member 120 but also from the sliding member 130. For this reason, the force which acts on a contact object from the linear member 41 can be improved, and the object of a biological lumen can be effectively cut by the linear member 41. FIG. The sliding member 130 is preferably formed of a material having high rigidity (for example, metal) so that a rotational force can be transmitted.

  When the sliding convex portion 131 of the sliding member 130 slides in the distal direction in the sliding groove 121, the sliding convex portion 131 abuts on the first regulating convex portion 122, and movement in the distal direction is restricted. That is, the first restricting convex portion 122 and the sliding convex portion 131 (second restricting convex portion) restrict the maximum protruding distance of the sliding member 130 in the distal direction with respect to the cylindrical member 120. Thereby, the magnitude | size of the cutting part 40 can be limited to a predetermined range, and it can suppress that the outer diameter of the cutting part 40 becomes small too much. Further, the sliding member 130 can be prevented from falling off the cylindrical member 120. In addition, although the 2nd control convex part which collides with the 1st control convex part 122 is the sliding convex part 131 in this embodiment, the structure different from the sliding convex part 131 may be sufficient. Further, the first restricting convex portion 122 is formed at the distal end of the sliding groove 121, but may be formed at a position different from the distal end of the sliding groove 121.

  The configuration for rotating the sliding member 130 in conjunction with the rotation of the cylindrical member 120 around the axis and the configuration for restricting the movement of the sliding member 130 in the axial direction are not limited to the above configuration. For example, the sliding protrusion may be formed on the cylindrical member instead of the sliding member, and the sliding groove may be formed on the sliding member instead of the cylindrical member. In the above example, two slide protrusions 131, slide grooves 121, and first restricting protrusions 122 are provided, but the number is not limited. Further, the shape of the sliding protrusion and the sliding groove is not limited as long as the relative rotation of the cylindrical member and the sliding member can be restricted. For example, in the cross section orthogonal to the sliding direction, if the maximum outer diameter of the sliding member is larger than the minimum inner diameter of the cylindrical member, the relative rotation of the cylindrical member and the sliding member can be restricted. Further, the sliding member may slide on the outer peripheral surface side instead of sliding on the inner peripheral surface side of the cylindrical member. That is, the sliding member may be a cylinder that covers the outer peripheral surface of the cylindrical member. In this case, the first restricting convex portion is formed not on the inner peripheral surface of the cylindrical member but on the outer peripheral surface, and the second restricting convex portion is formed on the inner peripheral surface instead of the outer peripheral surface of the sliding member. The

  The present invention is not limited to the above-described embodiments, and various modifications can be made by those skilled in the art within the technical idea of the present invention. For example, an object to be cut by the medical device is not limited to a calcified lesion, and any object that can exist in a living body lumen can be applicable. Further, the body lumen into which the medical device is inserted is not limited to a blood vessel, and may be, for example, a vascular tube, a ureter, a bile duct, a fallopian tube, a liver tube, or the like.

  Moreover, the cross-sectional shape of the linear member which comprises a cutting part does not need to be circular. For example, the cross-sectional shape of the linear member may be an ellipse, a quadrangle, or the like. For example, when the cross-sectional shape of the linear member has a corner such as a quadrangle, this corner can be used as a blade (convex portion) for cutting the lesion.

DESCRIPTION OF SYMBOLS 10 Medical device 11 Guide wire lumen 20,120 Cylindrical member 30,130 Sliding member 41,91,101,111 Linear member 44 Convex part 92,102 Protruding part 121 Sliding groove 122 1st regulation convex part 131 Sliding convex part (second regulating convex part)
L lesion

Claims (7)

A medical device that is inserted into a biological lumen to cut an object in the biological lumen,
A long cylindrical member that is rotationally driven;
A tubular member that is slidably disposed in the axial direction inside or outside the cylindrical member, and a sliding member that extends more distally than the cylindrical member;
At least one linear member having a distal end coupled to the sliding member and a proximal end coupled to the tubular member;
A medical device in which the linear member bends as the sliding member slides in an axial direction with respect to the cylindrical member.   The medical device according to claim 1, wherein the sliding member rotates in conjunction with rotation around the axial center of the cylindrical member.   The sliding member and the cylindrical member have a protruding protruding protrusion for limiting relative rotation around the axis and a sliding groove into which the sliding protrusion is slidably fitted in the axial direction. The medical device according to claim 2.   The medical device according to claim 1, wherein the linear member has a plurality of convex portions on a surface thereof.   The medical device according to any one of claims 1 to 4, wherein the linear member has a protruding portion that bends and protrudes inward in the radial direction of the cylindrical member or the sliding member.   The medical device according to any one of claims 1 to 5, wherein the linear member is disposed in a spiral shape that winds an axis of the cylindrical member.   The cylindrical member has a first restricting convex portion protruding inward or outward in the radial direction, and the sliding member moves in a distal direction with respect to the cylindrical member. The medical device according to any one of claims 1 to 6, further comprising a second restricting convex portion against which the first restricting convex portion abuts.

Images