JP6624600B2 - catheter - Google Patents

Description

  The present invention relates to a medical catheter.

  2. Description of the Related Art Conventionally, a catheter including a catheter main body formed by spirally winding an element wire and a distal end tip fixed to a distal end of the catheter main body has been known.

  For example, Patent Literature 1 discloses a medical treatment tool (catheter) in which a metal tip is attached to a tip of a coil body around which a metal wire is wound.

JP 2007-98120 A

  However, in the catheter described in Patent Literature 1, since a single wire is a single wire (single-wire coil) or a plurality of wires is multi-wire (multi-wire coil), and thus the coil is configured. The single coil body has a problem that the flexibility is good but the torque transmission property is reduced, and the multi-row coil body has a problem that the torque transmission property is good but the flexibility is reduced. Therefore, it has been difficult to easily insert the catheter into an occluded portion of a blood vessel.

  Further, in the catheter described in Patent Document 1, when the degree of curvature of the catheter is increased, the catheter itself may be slightly deformed, but once deformed, it does not return to the original state. In that case, there is a problem that operation of a combined device such as a guide wire becomes difficult.

  Further, in the catheter described in Patent Document 1, since a distal tip made of metal is separately connected to the distal end of the catheter body, stress is easily concentrated on the boundary between the catheter body and the distal tip, and the catheter breaks at the boundary. There is a problem that is easily generated.

Further, since the catheter described in Patent Document 1 has a distal tip made of metal separately connected to the distal end of the catheter main body, a combined device such as a guide wire inserted into the lumen of the catheter has a distal end connected to the catheter main body. There is also a problem that the device is caught on a boundary portion with the chip, and resistance is increased when pushing and pulling the combined device.

  Furthermore, the catheter described in Patent Literature 1 is configured such that a single wire is a single wire (single wire coil) or a plurality of wires are multiple wires (multi-wire coil) to form a coil. Since the wires constituting the body are inclined with respect to the longitudinal direction of the catheter, there is a problem that the insertion resistance increases when the catheter is inserted into a blocked portion of a blood vessel or the like.

  A first object of the present invention is to provide a catheter which has excellent torque transmission and excellent flexibility and can be easily inserted into an occluded part of a blood vessel.

A second object of the present invention is to provide a catheter in which the degree of curvature of the catheter is increased and the catheter easily returns to its original shape even when the catheter is deformed.

Further, a third object of the present invention is to provide a catheter which prevents breakage at the boundary between the catheter main body and the distal end tip and improves the operability of a combined device such as a guide wire.

  A first aspect of the present invention is a catheter including a coil body in which a stranded wire obtained by twisting a plurality of strands is wound in a hollow spiral shape.

  A second aspect of the present invention is the catheter according to the first aspect, wherein the coil body is formed by winding a plurality of the stranded wires in a hollow spiral shape.

  According to a third aspect of the present invention, in the first aspect of the invention or the second aspect of the invention, a tip portion of the coil body is formed by melting the element wire. It is a catheter.

  Further, according to a fourth aspect of the present invention, in the first aspect or the second aspect of the present invention, the distal end portion of the coil body is formed by melting an outer peripheral surface formed by melting the wire and the twisted wire. An inner peripheral surface in which a form of a line is retained.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects of the present invention, the inner layer formed inside the coil body, and the coil body formed outside the inner layer. And an outer layer formed so as to cover the catheter.

  Furthermore, a sixth aspect of the present invention is the invention according to the third aspect or the fourth aspect, wherein the inner layer formed inside the coil body and the area other than the tip end of the coil body are An outer layer formed so as to cover the coil body on the outer side of the inner layer.

  Since the catheter according to the first aspect of the present invention includes a coil body in which a stranded wire obtained by twisting a plurality of strands is wound in a hollow spiral shape, excellent torque transmission and excellent flexibility are achieved. It is possible to improve the insertability of the blood vessel into the occluded part. When the catheter is curved, the catheter can be easily returned to the original shape.

  According to the catheter of the second aspect of the present invention, in the catheter of the first aspect, since the coil body is formed by winding a plurality of stranded wires in a hollow spiral shape, the effect of the catheter of the first aspect is improved. In addition, it is possible to further improve the insertability of the blood vessel into the occluded part, and to improve the operability of the combined device such as a guide wire. When the catheter is curved, the catheter can be more easily returned to the original shape.

  The catheter according to the third aspect of the present invention is the catheter according to the first aspect or the catheter according to the second aspect, wherein the distal end portion of the coil body is formed by melting the element wire. In addition to the effects of the catheter or the catheter of the second aspect, breakage at the boundary between the catheter body and the distal end can be prevented, and the operability of a combined device such as a guidewire can be improved.

  A catheter according to a fourth aspect of the present invention is the catheter according to the first aspect or the catheter according to the second aspect, wherein a distal end portion of the coil body has an outer peripheral surface formed by melting a strand and a stranded wire. And the inner peripheral surface in which the catheter body of the first aspect or the catheter of the second aspect is provided. In addition, the guide wire and the like are prevented from being broken at the boundary between the catheter body and the distal end. The operability of the combined device can be improved, and the operability of inserting the blood vessel into a closed portion or the like can be further improved.

  A catheter according to a fifth aspect of the present invention is the catheter according to any one of the catheters according to the first aspect to the fourth aspect, wherein the inner layer formed inside the coil body and the coil body are coated outside the inner layer. And the outer layer formed as described above, in addition to the effect of the catheter according to any one of the first to fourth aspects, further improves the insertability into the occluded part of the blood vessel, and further includes a guide wire and the like. The operability of the combined device can be further improved.

  The catheter according to a sixth aspect of the present invention is the catheter according to the third aspect or the catheter according to the fourth aspect, wherein the inner layer formed inside the coil body and the outer layer outside the inner layer in a region other than the distal end portion of the coil body. And the outer layer formed so as to cover the coil body, in addition to the effect of the catheter of the third aspect or the catheter of the fourth aspect, further improves the insertability of the blood vessel into the occluded part. In addition, the operability of a combined device such as a guide wire can be further improved.

It is a top view of a catheter of a 1st embodiment of the present invention. FIG. 2 is a sectional view taken along line AA of FIG. 1. FIG. 2 is a partially enlarged view showing a distal end portion of the catheter according to the first embodiment. FIG. 4 is a partial sectional view taken along line BB of FIG. 3. It is sectional drawing of the catheter of 2nd Embodiment. It is the elements on larger scale which show the front-end | tip part of the catheter of 2nd Embodiment. FIG. 7 is a partial sectional view taken along line CC of FIG. 6. It is a top view of a catheter of a 3rd embodiment. It is the elements on larger scale which show the front-end | tip part of the catheter of 3rd Embodiment. FIG. 10 is a partial sectional view taken along line DD of FIG. 9. FIG. 10 is an end view taken along line EE of FIG. 9. It is the elements on larger scale which show the front-end | tip part of the catheter of 4th Embodiment. FIG. 13 is a partial sectional view taken along line FF of FIG. 12. It is a fragmentary sectional view showing the tip part of the catheter of a 5th embodiment. It is a fragmentary sectional view showing the tip part of the catheter of a 6th embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(1st Embodiment)
1 is a plan view of a catheter according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line AA of FIG. 1, and FIG. 3 shows a distal end portion of the catheter according to the first embodiment. FIG. 4 is a partial enlarged view, and FIG. 4 is a partial sectional view taken along line BB of FIG.

As shown in FIG. 1, the catheter 1 includes an operation unit 10 operated by a technician, and a coil body 20 connected to a distal end of the operation unit 10.

  Further, the coil body 20 has a main body 21 extending from the operation section 10 toward the distal end, and a distal end 22 located at the distal end of the main body 21. A hollow part 25 (see FIG. 2) is formed in the part 22.

  Further, as shown in FIG. 2, the main body 21 of the coil body 20 is formed in a tube shape wound into a multi-strand coil using eight bundles of stranded wires 30. The twisted wire 30 is configured by twisting six stainless steel second wires 31b serving as side wires around a stainless steel first wire 31a serving as a core wire.

  Further, as shown in FIG. 3 and FIG. 4, the distal end portion 22 of the coil body 20 is configured such that the end portion of each stranded wire 30 located at the distal end portion 22 is melted by YAG welding or the like and joined, so that the first The element wire 31 a and the second element wire 31 b are configured so as not to be unwound, and a tip opening 26 communicating with the hollow portion 25 is formed.

  In the catheter 1 of the present embodiment, since the coil body 20 is formed by spirally winding the plurality of stranded wires 30, the torque transmission can be improved without impairing the flexibility, and the inside of the occluded portion of the blood vessel can be improved. It is possible to improve the insertability into the device.

  Further, when the degree of curvature of the catheter 1 becomes large during use, the catheter can be easily returned to the original shape.

  As shown in FIGS. 1 and 3, on the inner peripheral surface side and the outer peripheral surface of the coil body 20, the twist direction of the second strand 31 b constituting the stranded wire 30 is substantially parallel to the longitudinal direction of the catheter. Because of this orientation, the ease of insertion into the occluded part of the blood vessel and the operability of the combined device such as a guide wire are improved.

  In the present embodiment, stainless steel is used as the material of the first strand 31a and the second strand 31b, but a superelastic alloy such as a Ni-Ti alloy, or another metal strand such as a tungsten strand may be used. good.

  Further, in the present embodiment, the number of strands constituting the stranded wire 30 is seven, but the number of the first strands 31a and the second strands 31b constituting the strand is not particularly limited and may be two or more. The number is preferably 3 to 10 from the viewpoint of torque transmission and flexibility.

  In addition, the coil body 20 may be formed by winding one strand of the stranded wire 30. However, it is preferable to form the coil body by winding a plurality of bundles of the stranded wire 30 to further improve the insertability into the occluded part of the blood vessel. Therefore, the operability of the combined device such as a guide wire can be further improved, and when the catheter is curved, the catheter can be more easily returned to the original shape.

  Further, in the present embodiment, the distal end portion 22 is formed by melting the first strand 31a and the second strand 31b constituting the strand 30. However, as another embodiment, a plurality of strands 30 are used. The main body 21 may be configured, and the distal end 22 may be provided separately from the main body 21. Even in that case, the catheter 1 has excellent torque transmission properties and excellent flexibility, improves the insertion property into the occluded part of the blood vessel, and when the catheter is curved, the catheter can be easily returned to the original state. It can be returned to its shape.

  However, it is better to form the distal end portion 22 by melting the first strand 31a and the second strand 31b constituting the stranded wire 30. Operability and shape recovery of the catheter can be further improved.

  Further, in the present embodiment, the distal end portion 22 is melted by welding the first strand 31a and the second strand 31b constituting the stranded wire 30, but may be formed by a method other than welding. For example, the distal end portion 22 may be configured by brazing the first strand 31a and the second strand 31b.

(2nd Embodiment)
FIG. 5 is a sectional view of the catheter of the second embodiment, FIG. 6 is a partially enlarged view showing a distal end portion of the catheter of the second embodiment, and FIG. 7 is a partial sectional view taken along line CC of FIG. FIG.

As shown in FIG. 5, when the catheter according to the second embodiment is compared with the catheter 1 according to the first embodiment, the difference lies in the number of twisted wires. That is, the main body 21 of the coil body 20 according to the first embodiment is wound in a multi-strand coil shape using eight bundles of stranded wires 30 (see FIG. 2), but the coil body 40 according to the second embodiment is used. The main body 41 is wound in a single-strand coil shape using one bundle of the stranded wire 30.

The coil body 40 is configured such that the stranded wire 50 is configured by twisting six stainless steel second wires 51b serving as side wires around a stainless steel first wire 51a serving as a core wire. It has a main body portion 41 extending from the operation portion 10 toward the front end side, and a front end portion 42 located on the front end side of the main body portion 41, and a hollow portion is provided in the main body portion 41 and the front end portion 42. 45 is formed, and the distal end 42 of the coil body 40 is melted by YAG welding or the like at the end of each of the stranded wires 50 located at the distal end 22 and joined, so that the first strand 51a is formed. The second embodiment is similar to the first embodiment in that the second wire 51b is configured so as not to be unwound.

  Since the coil body 40 of the present embodiment is configured by spirally winding a bundle of stranded wires 50, the flexibility can be further improved as compared with the catheter of the first embodiment, and the catheter is curved. In such a case, the catheter can be easily returned to the original shape.

  However, as shown in FIG. 6, since the twisting direction of the second strand 51b constituting the twisted wire 50 is substantially perpendicular to the longitudinal direction of the catheter, the insertion property of the blood vessel into the occluded portion is improved. In addition, the operability of the combined device such as a guide wire is slightly inferior to the catheter of the first embodiment.

(Third embodiment)
FIG. 8 is a plan view of the catheter of the third embodiment, FIG. 9 is a partially enlarged view showing a distal end portion of the catheter of the third embodiment, and FIG. 10 is a partial cross-sectional view taken along the line DD of FIG. FIG. 11 is an end view taken along line EE of FIG.

When the catheter 5 in the third embodiment is compared with the catheter 1 in the first embodiment, the difference lies in the structure of the distal end portion. That is, the distal end portion 22 of the coil body 20 according to the first embodiment is formed by melting the entire first wire 31a and the second wire 31b constituting the stranded wire 30, but the coil body according to the third embodiment is formed. As shown in FIG. 10, the distal end 62 of the 60 has an inner peripheral surface 64 at the distal end 62 in which the form of the stranded wire 30 is maintained without melting the second strand 31 b. That is, the inner peripheral surface 64 has an uneven shape based on the outer shape of the second strand 31b that forms the stranded wire 30.

The coil body 60 has a main body 61 extending from the operation section 10 toward the distal end, and a distal end 62 located on the distal end side of the main body 61. The point that the hollow portion 25 is formed in the portion 62 is the same as in the first embodiment.
Moreover, the point that the main-body part 61 of the coil body 60 is wound in the shape of a multi-strand coil using eight bundles of the stranded wires 30 is also the same as in the first embodiment.

  On the other hand, as shown in FIGS. 9, 10 and 11, the outer peripheral surface 63 of the distal end portion 62 has the first strand 31 a and the second strand 31 b constituting each of the twisted wires 30 located at the distal end 62. The first wire 31a and the second wire 31b are melted by welding or the like, so that the surface is smooth without being melted.

  FIG. 11 shows a state in which all the first wires 31a and all the second wires 31b located outside are melted. However, depending on the welding state, some of the first wires 31a and some of the first wires 31a are not melted. The second strand 31b may not melt. Even in such a case, the outer peripheral surface 63 may be flat.

  By using welding, the first wire 31a and the second wire 31b corresponding to the inner circumferential surface 64 are not melted, and only the first wire 31a and the second wire 31b corresponding to the outer circumferential surface 63 are easily melted. Can be melted.

  Further, a distal end opening 66 formed at the distal end of the distal end portion 62 communicates with the hollow portion 25, and as shown in FIG. 10, adjacent stranded wires 30 located at the distal end of the distal end portion 62 are welded. The configuration is such that the stranded wire 30 cannot be unraveled.

  In the coil body 60 of the present embodiment, since the outer peripheral surface 63 of the distal end portion 62 is a smooth surface, resistance when entering the occluded portion of a blood vessel is reduced, and insertion into the occluded portion is performed. Performance can be improved. On the other hand, since the inner peripheral surface 64 of the distal end portion 62 has an uneven shape in which the form of the stranded wire 60 is maintained, the inner peripheral surface 64 is used with a combined device such as a guide wire inserted into the hollow portion 25 of the coil body 60. The contact area with the peripheral surface 64 is reduced, whereby the sliding resistance is suppressed and the operability is improved.

In addition, since the twisting direction of the second strand 31b constituting the stranded wire 30 is substantially parallel to the longitudinal direction of the catheter, the operability of a combined device such as a guidewire can be further improved. it can.

  In addition, since the catheter 5 is integrally formed of the same member from the distal end portion 62 to the main body portion 61 of the coil body 60, stress concentration that causes breakage at a boundary portion between the distal end portion 62 and the main body portion 61 is prevented. Does not occur.

  Further, since the coil body 60 is formed by winding the plurality of stranded wires 30 in a multi-strand coil shape, the rigidity of the coil body 60 is further increased, and the penetration into the closed portion and the like is more excellent. I have.

  In the present embodiment, the smooth outer peripheral surface 63 and the inner peripheral surface 64 holding the form of the stranded wire 60 are formed at the distal end portion 62 of the coil body 60. You may make it have the inner peripheral surface in which the form of the stranded wire was maintained.

  However, forming the distal end portion 62 of the coil body 60 with the smooth outer peripheral surface 63 and the inner peripheral surface 64 holding the form of the stranded wire 60 has an advantage that the distal end portion does not need to be formed by a separate component. .

  Further, in the present embodiment, the distal end portion 42 is formed by melting the first strand 51a and the second strand 51b constituting the stranded wire 50. However, as another embodiment, the main body portion is formed by the stranded wire 50. 41, and the distal end portion 42 may be provided separately from the main body portion 41. Even in that case, the catheter 1 has excellent torque transmission properties and excellent flexibility, improves the insertion property into the occluded part of the blood vessel, and when the catheter is curved, the catheter can be easily returned to the original state. It can be returned to its shape.

  However, it is better to form the distal end portion 42 by melting the first strand 51a and the second strand 51b constituting the stranded wire 50. Operability and shape recovery of the catheter can be further improved.

  Further, in the present embodiment, the distal end portion 42 is melted by welding the first strand 51a and the second strand 51b constituting the stranded wire 50, but may be formed by a method other than welding. For example, the distal end portion 42 may be configured by brazing the first strand 51a and the second strand 51b.

(Fourth embodiment)
FIG. 12 is a partially enlarged view showing a distal end portion of the catheter according to the fourth embodiment, and FIG. 13 is a partial sectional view taken along line FF of FIG.

When comparing the catheter of the fourth embodiment with the catheter 5 of the third embodiment, the difference lies in the number of twisted wires. That is, the main body part 61 of the coil body 60 of the third embodiment is wound in a multi-strand coil shape using eight bundles of the stranded wires 30, but the main body 81 of the coil body 80 of the fourth embodiment is It is wound in a single strip coil using one bundle of stranded wires 50.

The coil body 80 is configured such that the stranded wire 50 is configured by twisting six stainless steel second wires 51b serving as side wires around a stainless steel first wire 51a serving as a core wire. It has a main body 81 extending from the operation section 10 toward the distal end, and a distal end 82 located on the distal end side of the main body 81, and has a hollow portion inside the main body 81 and the distal end 82. 45 is formed, and the distal end 82 of the coil body 80 is melted by YAG welding or the like at the end of each of the stranded wires 50 located at the distal end 82 and joined to form the first strand 51a. The third embodiment is the same as the third embodiment in that the second wire 51b is configured so as not to be unwound.

  On the other hand, as shown in FIG. 13, the outer peripheral surface 83 of the distal end portion 82 is formed by melting the first strand 51 a and the second strand 51 b constituting each stranded wire 50 located at the distal end portion 82 by YAG welding or the like. By being connected, the first wire 51a and the second wire 51b are not melted and are made to be smooth surfaces.

  Also, by using welding, the first strand 51a and the second strand 51b corresponding to the inner peripheral surface 84 are not melted, and only the first strand 51a and the second strand 51b corresponding to the outer peripheral surface 83 are not melted. Can be easily melted.

  The distal end opening 86 formed at the distal end of the distal end portion 82 communicates with the hollow portion 45, and the adjacent stranded wires 50 located at the distal end of the distal end portion 82 are welded to form the stranded wire 50. Is configured so that it cannot be unraveled.

  Even in the coil body 80 of the present embodiment, since the outer peripheral surface 83 of the distal end portion 82 is a smooth surface, resistance at the time of entering a blocked portion of a blood vessel or the like is reduced, and insertion into the blocked portion is performed. Performance can be improved. On the other hand, since the inner peripheral surface 84 of the distal end portion 82 has an uneven shape in which the form of the stranded wire 80 is maintained, the inner peripheral surface 84 is used with a combined device such as a guide wire inserted into the hollow portion 45 of the coil body 80. The contact area with the peripheral surface 84 is reduced, whereby the sliding resistance is suppressed and the operability is improved.

  In addition, since the catheter 1 is integrally formed of the same member from the distal end portion 82 of the coil body 80 to the main body portion 81, stress concentration that causes breakage at a boundary portion between the distal end portion 82 and the main body portion 81 is prevented. Does not occur.

In the present embodiment, the smooth outer peripheral surface 83 and the inner peripheral surface 84 holding the form of the stranded wire 80 are formed at the distal end portion 82 of the coil body 80. You may make it have the inner peripheral surface in which the form of the stranded wire was maintained.
However, forming the distal end portion 82 of the coil body 80 with the smooth outer peripheral surface 83 and the inner peripheral surface 84 holding the form of the stranded wire 80 has the advantage that the distal end portion does not need to be formed of a separate component. .

(Fifth embodiment)
FIG. 14 is a partial cross-sectional view showing a distal end portion of the catheter according to the fifth embodiment.

The catheter according to the fifth embodiment is obtained by coating the outer periphery of the catheter according to the first embodiment with a resin. Specifically, an inner layer 92 is formed inside the coil body 100 along the hollow portion 25, and an outer layer 94 is formed outside the inner layer 92 so as to cover the coil body 100.

According to the catheter of the fifth embodiment, the catheter has excellent torque transmission properties and excellent flexibility, further improves the insertability of the blood vessel into the occlusion, and further enhances the operability of the combined device such as a guide wire. Can be improved.

  Although the catheter according to the present embodiment is such that the outer periphery of the catheter in the first embodiment is covered with a resin, the outer periphery of the catheter in the catheter according to the second embodiment may be covered with a resin.

  Further, the distal end of the coil body 20 in the first embodiment or the distal end of the coil body 40 in the second embodiment is provided separately from the main body 21 or the main body 41 and the outer periphery of the catheter is coated with resin. It is good.

(Sixth embodiment)
FIG. 15 is a partial cross-sectional view illustrating a distal end portion of the catheter according to the sixth embodiment.

The catheter according to the sixth embodiment is obtained by coating a part of the outer periphery of the catheter according to the third embodiment with a resin. Specifically, an inner layer 112 is formed inside the coil body 120 along the hollow portion 45, and an outer layer 114 is formed outside the inner layer 112 so as to cover the coil body 120 other than the outer peripheral surface 63. .

  According to the catheter of the sixth embodiment, the catheter has excellent torque transmission properties and excellent flexibility, further improves the insertability of the blood vessel into the occlusion, and further enhances the operability of the combined device such as a guide wire. Can be improved.

  Although the catheter according to the present embodiment is such that the outer periphery of the catheter in the third embodiment is covered with a resin, the outer periphery of the catheter in the catheter according to the fourth embodiment may be covered with a resin.

  In addition, the outer periphery of a catheter in which the distal end of the coil body 60 in the third embodiment or the distal end of the coil body 80 in the fourth embodiment is provided separately from the main body 61 or the main body 81 is covered with a resin. It is good.

1,5 Catheter 10 Operation part 20,40,60,80,100,120 Coil body 21,41,61,81 Body part 22,42,62,82 Tip part 63,83 Outer surface 64,84 Inner surface 25 , 45 Hollow part 26, 66, 86 Tip opening 30, 50 Twisted wire 31a, 51a First strand (strand)
31b, 51b 2nd strand (strand)
92,112 Inner layer 94,114 Outer layer

Claims (4)

A catheter, comprising a coil body wound in a hollow spiral shape with a stranded wire obtained by twisting a plurality of strands,
The coil body, a main body configured by the stranded wire,
A tip portion located on the tip side of the main body portion, formed by a stranded wire continuous with the stranded wire of the main body portion,
The tip portion has a flat outer peripheral surface formed by melting the strand of the stranded wire, and an inner peripheral surface having an uneven shape in which the form of the stranded wire is maintained at a position corresponding to the flat outer peripheral surface. A catheter comprising:   The catheter according to claim 1, wherein the coil body is formed by winding a plurality of the stranded wires in a hollow spiral shape. An inner layer formed inside the coil body,
The catheter according to claim 1, further comprising an outer layer formed so as to cover the coil body on an outer side of the inner layer. An inner layer formed inside the coil body,
The area | region other than the front-end | tip part of the said coil body is provided with the outer layer formed so that the said coil body might be covered outside the said inner layer, The Claim 1 or Claim 2 characterized by the above-mentioned. Catheter.