JP6377219B2 - Method for manufacturing medical ablation catheter - Google Patents

Description

  The present invention relates to a method for producing a medical ablation catheter (hereinafter sometimes simply referred to as “ablation catheter” or “catheter”).

  Among hypertension, treatment-refractory (refractory) hypertension is generally hypertension that does not decrease to the target blood pressure even when three or more antihypertensive agents are used. Stroke, heart attack, heart failure, kidney It is a very dangerous chronic disease because it is associated with increased cardiovascular risk such as disease. Approximately one-tenth of high blood pressure patients (about 100 million people worldwide) are said to have treatment-resistant hypertension.

  In recent years, renal artery ablation has been shown to be effective as a treatment method for treatment-resistant hypertension. Renal artery ablation is a procedure that lowers blood pressure by blocking the renal sympathetic nerves around the renal artery by cauterization. In this method, for example, an ablation catheter equipped with an electrode (cautery part) that generates microwaves is inserted into the renal artery, and a part of the inner wall surface of the renal artery is irradiated with the microwaves intensively. The part is cauterized. When the renal sympathetic nerve cells that run through the renal arteries are cauterized, the sympathetic nerves are blocked. In a procedure using an ablation catheter, surgery is performed so that the site to be cauterized is spaced apart and spirals (spiral) on the inner wall of the renal artery. If the parts to be cauterized (the parts to be ablated) are scattered in a spiral shape, each part to be ablated exists at a different position in the flow direction of the renal arteries. Since the swollen sites do not overlap, the renal artery is less likely to stenosis.

  However, such an operation requires skilled techniques and requires a long procedure time. Patent Literature 1 and Patent Literature 2 describe a basket type ablation catheter in which a plurality of parallel wires (thin wires) are arranged in a basket shape. In these ablation catheters, each ablation part attached to each wire is disposed at a different position in the axial direction of the ablation catheter. Therefore, by design, by inserting an ablation catheter into the renal artery, the ablation element can be in close contact with the inner wall of the renal artery, and different parts of the renal artery in the flow direction can be cauterized at the same time. Time can be shortened.

International Publication No. 2013/077283 U.S. Pat. No. 8,454,594

However, when the ablation catheter is actually inserted into the renal artery, each ablation part may not necessarily be arranged at the designed position, and the ablation part is partially concentrated in the renal artery. There is a case. In this case, when the cauterization site in the renal artery swells, the swelling sites may overlap with each other, and the renal artery may be stenotic.
Therefore, an object of the present invention is to provide a method for manufacturing a medical ablation catheter in which cauterization of the ablation portion is unlikely to occur.

In order to solve the above problems, the present inventors thoroughly verified the operation of the ablation catheter.
As described in Patent Document 1 and Patent Document 2, the ablation catheter has a tubular sheath member and a plurality of wires (wires) formed in a basket shape. The reason why the wire is formed in a basket shape is to ensure that the cautery part is in close contact with the inner wall of the renal artery. On the other hand, when the wire is moved in the renal artery, the wire is stored compactly in a narrow space in the sheath member. In the verification of the operation of the ablation catheter, the present inventors, when a wire is pulled into the sheath member, one wire is in contact with the inner wall of the outlet peripheral edge of the sheath member while disposing the distal side of the ablation catheter. Folded in the sheath member while falling clockwise, and another wire is folded while falling counterclockwise, that is, in order to mix clockwise and counterclockwise wires, It was found that each wire was folded irregularly in the left and right within the sheath member. If each wire is stored irregularly inside the sheath member, an irregular state remains even when the wire expands to the outside of the sheath member on the distal side, and the cautery part is as designed. Not placed in.

  During further investigation, the present inventors have found that there is a difference in the clockwise direction or the counterclockwise direction in the direction of falling when the wire is drawn into the sheath member. It was thought that it was divided into those that happened to fall clockwise, and those that happened to fall counterclockwise, depending on the subtle differences in how the force was applied to each wire. Therefore, the present inventors, even if there is a slight difference in the shape of each wire or there is some variation in the force applied to each wire, when the wire is pulled into the sheath member, all the wires The present invention has been completed by repeatedly studying the configuration for folding in the sheath member while falling in the same direction (for example, clockwise).

That is, the first medical ablation catheter of the present invention that has solved the above problems is
A plurality of wires arranged in parallel,
A shochu portion provided on each of the wires;
A tubular member that houses the wire;
The wire rod is configured to be housed in the tubular member and to be advanced to a distal side outside the tubular member, and the wire rod is disposed on a distal side outside the tubular member. In at least a part of the portion that has advanced to the center, the cylindrical member circulates in the axial direction, and the wrapping direction of all the wire members is the same.

  As a precaution, the term “around” means that the wire does not indicate the dynamic state of the wire, but the static shape of the wire, and in the partial section of the wire, the proximal side of the wire The state which is displaced to the circumferential direction centering on the axis | shaft of a cylindrical member as it goes to a distal side from is described.

  In the present invention, since all the wires are circulated in the same direction in some sections, when the wires are drawn into the tubular member (sheath member), the same angle with respect to the inner wall of the outlet peripheral edge of the tubular member Therefore, all the wires are folded into the cylindrical member while falling in the same circumferential direction (for example, clockwise). Therefore, the problem of non-uniformity of the arrangement of the cauterization part in the cylindrical member has been eliminated, so that when the thin wire advances to the outside of the cylindrical member and expands, it does not become an irregular state, Each shochu portion is easily arranged as designed.

The second medical ablation catheter of the present invention that has solved the above problems is
A plurality of wires arranged in parallel,
A shochu portion provided on each of the wires;
A tubular member that houses the wire;
The wire is configured to be able to be accommodated in the cylindrical member and to be advanced to the distal side outside the cylindrical member,
The wire is formed by twisting a plurality of fine wires, and the twist direction is the same in all the wires.

  A wire formed by twisting a plurality of thin wires tends to exhibit a twisted shape so as to draw a gentle spiral. Whether the direction in which the wire is spiraled is clockwise or counterclockwise depends on whether the twist direction of the fine wire is clockwise or counterclockwise. Therefore, if the twisting direction of the fine wire is unified to either the clockwise or counterclockwise direction, that is, if the twisting direction is the same in all the wires, the direction in which each wire is wound is also clockwise. Or counterclockwise. Then, when the wire is drawn into the tubular member, it comes into contact with the inner wall of the outlet peripheral portion of the tubular member at the same angle, so that all the wire rods fall in the same direction (for example, clockwise) and fall inside the tubular member. Folded to go. Therefore, it is considered that the problem of non-uniform arrangement of the cauterized portion when the wire is drawn into the cylindrical member is solved. For this reason, even when the fine wire advances to the outside of the cylindrical member and expands, it does not become an irregular state, and each cautery part is easily arranged as designed.

The third medical ablation catheter of the present invention that has solved the above problems is
A plurality of wires arranged in parallel,
A shochu portion provided on each of the wires;
A tubular member that houses the wire;
The wire rod is configured to be housed in the tubular member and to be advanced to a distal side outside the tubular member, and the wire rod is disposed on a distal side outside the tubular member. In at least a partial section of the part that has advanced to the axial direction of the cylindrical member, and the circumferential direction of all the wire is the same,
The wire is formed by twisting a plurality of fine wires, and the twist direction is the same in all the wires.

  The third medical ablation catheter of the present invention has the characteristics of the first medical ablation catheter and the characteristics of the second medical ablation catheter, and includes the first medical ablation catheter and the second medical ablation catheter. Similar to the medical ablation catheter, the problem of non-uniform arrangement of the cauterized portion when the wire is drawn into the cylindrical member is solved.

  In each of the medical ablation catheters described above, the wire has a configuration in which at least a part of the portion extending to the distal side of the cylindrical member protrudes outside the outer diameter of the cylindrical member; can do.

  In each of the medical ablation catheters described above, it is preferable that the ablation portions respectively provided on the wire are arranged at different positions in the axial direction of the cylindrical member.

  In each of the medical ablation catheters described above, the wire has at least two vertices at which the distance projecting outward from the outer diameter of the tubular member is maximized, and the first vertex has a first It is preferable that a second cautery part is provided at each of the cautery part and the second apex.

  In each of the above-mentioned medical ablation catheters, the first cauterization part and the second cauterization part provided on the same wire differ from each other by a predetermined angle in the direction of rotation with respect to the axial direction of the cylindrical member. Is preferably provided.

  In each of the above-mentioned medical ablation catheters, the distance between the most distal side and the most proximal side of the first cautery portions provided on each wire, and the respective wires A mode in which the distance between the most distal side and the most proximal side among the provided second cautery parts is different can be implemented.

  In a medical ablation catheter, it is desirable that the wire used has high elasticity. This is because the cauterized portion provided on the wire is securely adhered to the inner wall of the renal artery as described above. As a result of various trials and errors to produce a wire with increased elasticity, the inventors have found that the elasticity of the wire is increased when a medical ablation catheter is manufactured by the following method.

That is, a method for manufacturing a medical ablation catheter having a wire with increased elasticity includes a plurality of wires arranged in parallel, an ablation portion provided on each of the wires, and a cylindrical member that accommodates the wire. The wire is configured to be housed in the tubular member and to be advanced to the distal side outside the tubular member, and to advance to the distal side of the tubular member. At least a part of the part is a method for producing a medical ablation catheter that protrudes outside the outer diameter of the cylindrical member,
Bending the wire rod in a first direction at the first predetermined position of the wire rod, and bending the wire rod in the first direction at a second predetermined position different from the first predetermined position. A first shaping step including a step of bending so as to be convex in a second direction different from
After the first shaping step, a second shaping step is included in which at least a part of the wire rod is bent so as to protrude outward from the outer diameter of the cylindrical member.

  In the manufacturing method of the medical ablation catheter, after the first shaping step and before the second shaping step, the wire bent in the first shaping step is stretched to be attached once. It is desirable to add a step of relaxing the projected shape.

  In the method for manufacturing the medical ablation catheter, it is desirable that the first direction and the second direction are opposite to each other.

  In the manufacturing method of the medical ablation catheter, it is desirable that a plurality of the first predetermined positions and the second predetermined positions exist in the same wire.

According to the present invention, (1) the wire constituting the medical ablation catheter circulates with respect to the axial direction of the tubular member, and all the wires have the same circulatory direction, or (2 ) The wire constituting the medical ablation catheter is formed by twisting a plurality of fine wires, and the twist direction is the same in all the wires,
When the fine wire advances to the outside of the tubular member and expands, it does not become an irregular state, and has an excellent effect that each cautery part is easily arranged as designed.

FIG. 1 is a perspective view of a medical ablation catheter according to a first embodiment of the present invention. FIG. 2 is a cylindrical projection of the wire of the medical ablation catheter according to the first embodiment of the present invention. FIG. 3 is a side view of the medical ablation catheter according to the first embodiment of the present invention as seen from the distal side. 4 (a) is a partial perspective view of the wire of the medical ablation catheter according to the first embodiment of the present invention, and FIG. 4 (b) is a medical ablation catheter according to the second embodiment of the present invention. FIG. 4C is a partial perspective view of a wire of another medical ablation catheter according to the second embodiment of the present invention. FIG. 5 is a cylindrical projection of the wire of the medical ablation catheter according to the third embodiment of the present invention. FIG. 6 is a perspective view of the wire of the medical ablation catheter according to the fourth embodiment of the present invention. Fig.7 (a) is a perspective view of the medical ablation catheter concerning Embodiment 5 of this invention, FIG.7 (b) is a side view for every wire of the medical ablation catheter. FIGS. 8A to 8C are views showing a partial manufacturing process of the medical ablation catheter according to the sixth embodiment of the present invention. FIG. 9 is a diagram showing a partial manufacturing process of the medical ablation catheter according to the sixth embodiment of the present invention.

  Hereinafter, the present invention will be described in more detail based on the following embodiments, but the present invention is not limited by the following embodiments as a matter of course, and appropriate modifications are made within a range that can meet the purpose described above and below. In addition, it is of course possible to carry out them, all of which are included in the technical scope of the present invention. In addition, in each drawing, although hatching, a member code | symbol, etc. may be abbreviate | omitted for convenience, in this case, a description and another drawing shall be referred. In addition, the dimensions of the various members in the drawings are given priority to contribute to the understanding of the features of the present invention, and may be different from the actual dimensions.

(Embodiment 1)
Hereinafter, a medical ablation catheter according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a medical ablation catheter according to a first embodiment of the present invention. In FIG. 1, a medical ablation catheter 1 includes a plurality of wire rods 2a to 2d arranged in parallel, cautery portions 3a to 3d respectively provided on the wire rods 2a to 2d, and a cylindrical shape that houses the wire rods 2a to 2d. Member 4. The wire rods 2a to 2d can be accommodated in the cylindrical member 4 and can be advanced to the distal side (left side in FIG. 1) outside the cylindrical member 4. The wires 2a to 2d are bound by the distal bundle 5 on the distal side, and are bound by the proximal bundle 6 on the proximal side. The form of binding is preferably heat welding or adhesion.

  A radiopaque marker 9 is attached to the distal bundle 5. This is for grasping the tip position of the medical ablation catheter during the procedure. If a radiopaque material is attached to the distal bundle 5 itself, the radiopaque marker 9 can be omitted, so that the diameter of the medical ablation catheter can be reduced.

  The cautery parts 3a to 3d are supplied with power by a conducting wire (not shown). It is desirable that the lead wires and the wire rods 2a to 2d are covered with a covering tube (not shown) so as not to come into contact with blood or the like in the renal artery. If the conductor has sufficient insulation measures such as enamel coating, for example, a coated tube may not be used.

  In at least a partial section of the portion extending to the distal side outside the cylindrical member 4, it circulates in the axial direction of the cylindrical member 4 (dashed line in FIG. 1), and all the wire rods The circulation directions of 2a to 2d are the same. Although it has already been described that the meaning of “circumference” is not dynamic, it will be described in more detail with reference to FIGS. 2 and 3.

  FIG. 2 is a cylindrical projection view in which the wire materials 2a to 2d of the medical ablation catheter according to the first embodiment of the present invention are projected onto the cylindrical projection plane 7 shown in FIG. The left side of FIG. 2 is the distal side of the medical ablation catheter as in FIG. 1 corresponds to the position of the circle A in FIG. 1, and the position of the circle B in FIG. 1 corresponds to the position of the circle A in FIG. Corresponds to the position of the circle B in FIG. Further, the direction X that goes around the one-dot chain line in FIG. 1 corresponds to the direction X from the upper side to the lower side in FIG. For example, when paying attention to the wire 2a, the wire 2a starts from the proximal circle B and then displaces the cylindrical projection surface 7 in the direction opposite to the direction X at least in the section α. That is, it circulates with respect to the axial direction of the cylindrical member 4 (the chain line in FIG. 1). Further, as shown in FIG. 2, the other wires 2b to 2d also circulate in the direction opposite to the direction X in the same manner as the wire 2a. As described above, the wires 2a to 2d circulate with respect to the axial direction of the tubular member 4 in the section [alpha], and all the wires 2a to 2d have the same circulation direction. The section α may start from the distal circle A and span a predetermined distance.

  FIG. 3 is a side view of the medical ablation catheter according to the first embodiment of the present invention viewed from the distal side (Y direction in FIG. 1). As can be seen from FIG. 3, all of the wires 2a to 2d start around in the same direction after leaving the proximal side (the back side of the drawing), and go through places where the cautery portions 3a to 3d are respectively provided. Finally, the distal bundles 5 are gathered together. As described above, the wire rods 2a to 2d circulate with respect to the axial direction of the tubular member 4 in at least some sections, and the circulatory directions of all the wire rods 2a to 2d are the same.

  Since the wire rods 2a to 2d are formed as described above, when the wire rod is drawn into the tubular member 4, all the wire rods 2a to 2d are folded into the tubular member 4 while falling in the X direction. go. Therefore, there is no non-uniformity in the arrangement of the cauterized parts 3a to 3d in the tubular member 4, and therefore, when the wire rods 2a to 2d extend to the outside of the cylindrical member 4 and expand, the cauterized parts 3a to 3d It becomes easy to arrange 3d as designed.

  It is preferable that the cauterization parts 3a-3d used in this Embodiment, a conducting wire (not shown), and a connection form are welding. The cautery parts 3a to 3d are preferably fixed on a coated tube (not shown) in order to stably measure the body potential, and the fixing method is adhesion, caulking, and the cautery parts 3a to 3d. The embankment is fixed to the both ends of the distal side and the proximal side by resin. It is preferable that the conducting wire connected to the cautery parts 3a to 3d is disposed inside the coated tube.

  The material of the cautery parts 3a to 3d used in the present embodiment is not particularly limited as long as it is a material that is electrically conductive and biocompatible. For example, a platinum iridium alloy, a stainless material, or the like is used. it can. There is no particular limitation on the cauterization method of the cautery parts 3a to 3d, for example, bipolar method (one electrode is installed on the wire 2a and the other electrode is installed outside the body), monopolar method (both one electrode and the other electrode are both wire 2a) Can be used. Also, the energy generation source for cauterization is not particularly limited in frequency, and there is no problem as long as it can be cauterized, such as high frequency and microwave.

  The material of the wire rods 2a to 2d used in the present embodiment is not particularly limited as long as the material has electrical conductivity and is biocompatible. For example, platinum iridium alloy, stainless steel material, tantalum, cobalt alloy, Nitinol (nickel titanium alloy) can be used. A material having radiopacity, for example, platinum, tungsten, etc., is preferable from the viewpoint that it can be contrasted in the fluoroscopy.

In this Embodiment, although the example using the four wire 2a-2d was demonstrated, there is no restriction | limiting in particular in a number. Considering the therapeutic effect, the ability to be accommodated in the tubular member 4, and the productivity of the medical ablation catheter, it is preferable to set the number of wires to four or five.

  The material of the radiopaque marker 9 used in the present embodiment is not particularly limited, and may be a metal or a resin as long as it can be confirmed by an operator by not transmitting X-rays. Even inorganic substances can be used. Further, the number of radiopaque markers 9 is not particularly limited.

  In the present embodiment, an example in which one cautery portion 3a is provided for one wire 2a has been described, but a plurality of cautery portions may be provided for one wire 2a.

  In this Embodiment, the wire 2a-2d was shown about the example currently bound by the distal side binding body 5 and the proximal side binding body 6. As shown in FIG. These bundles can prevent the wire from being disturbed during production. When the bundled body and the coated tube are connected to each other, it is preferable in that it can be fixed to the bundled body by heat welding and the manufacturing process of the ablation catheter becomes easy. It is also possible to peel and fix the portion where the coated tube is inserted into the distal bundle 5 and the proximal bundle 6.

<Usage example of medical ablation catheter>
In the blood vessel cauterization using the ablation catheter 1 configured as described above, first, the tubular member 4 is inserted into a patient's blood vessel. A bending mechanism (not shown) may be provided at the distal end portion of the cylindrical member 4 so that it can be easily inserted into a target blood vessel at a point where the blood vessel is branched. The tubular member 4 finally reaches the site for ablation.

  Next, the wire rods 2 a to 2 d are folded and inserted into the lumen of the tubular member 4 from the proximal side (proximal side) of the tubular member 4. Although it is simple and preferable that the wire rods 2a to 2d are folded by hand, an automatic folding mechanism may be provided, the wire rods may be folded by the operation of the folding mechanism, and may be inserted into the tubular member 4. However, according to the present invention, since the wire rods 2a to 2d are basically folded while they circulate in the same circumferential direction alone, there is an advantage that it is not necessary to use an automatic folding mechanism.

  Moreover, in order to make insertion into the cylindrical member 4 easier, a hydrophilic coating may be applied to the surfaces of the wires 2a to 2d. Under the present circumstances, about the surface of the cautery parts 3a-3d, if it can energize in the presence of blood, it is preferable from the viewpoint of insertion into the cylindrical member 4 and the blood vessel that the coating is applied. When it is impossible to energize, it is preferable to remove the coating on the surface of the cautery parts 3a to 3d or not to apply the coating on the surface of the cautery parts 3a to 3d.

  The cautery parts 3 a to 3 d exit from the outlet opening on the distal side of the tubular member 4 into the blood vessel and reach the target lesion part. When the cautery portions 3a to 3d exit from the outlet opening into the blood vessel, they are repelled by the spring properties (elasticity) of the wire rods 2a to 2d and spread outward, returning to their original shape before insertion. When the automatic folding mechanism is provided, the original shape is restored by releasing the folding mechanism. This spring property should just exist in at least one of a covering tube and wire 2a-2d, and can be freely selected in the condition used. The material for the wires 2a to 2d is not particularly limited as long as it has a spring property, but if a nickel titanium alloy is used, the shape restoring property is good. In addition, stainless steel material may be used in consideration of workability at low cost. Moreover, it is preferable to use a PEEK material for the covering tube in terms of preventing a short circuit due to a leakage current of the conducting wire. The folding mechanism can drive the cautery parts 3a to 3d with wires, static electricity, pressure, or the like, or the cautery parts 3a to 3d may be folded with a folding tube (not shown). To release the folding mechanism, an operation opposite to the folding operation may be performed.

(Embodiment 2)
Hereinafter, a medical ablation catheter according to a second embodiment of the present invention will be described with reference to the drawings. Since the medical ablation catheter according to the second embodiment basically has the same configuration as the medical ablation catheter according to the first embodiment, description of common parts is omitted.

  Fig.4 (a) is a partial perspective view of the wire 2a of the medical ablation catheter concerning Embodiment 1 of this invention. FIG.4 (b) is a perspective view of the wire 2a of the medical ablation catheter concerning Embodiment 2 of this invention. As shown in FIG. 4B, the wire 2a is formed by twisting a plurality of thin wires 10 together. FIG.4 (c) is a partial perspective view of the wire 2a of the other medical ablation catheter concerning Embodiment 2 of this invention. As shown in FIG. 4C, the wire 2 a is configured by twisting a plurality of thin wires 10 around the core 11.

  As shown in FIGS. 4B and 4C, when the wire 2a is constituted by the stranded wire of the thin wire 10, it is considered that the wire 10 is caused by the force that each thin wire 10 returns straight and the mutual tension. 2a tends to exhibit a twisted shape so as to draw a gentle spiral. Whether the direction in which the wire 2a spirals is clockwise or counterclockwise when viewed from the distal end side is determined by the twisting direction of the thin wire (Z in FIG. 4B). Therefore, if the twist direction of the thin wire 10 is unified to either the clockwise direction or the counterclockwise direction as viewed from the distal end side, that is, if the twist direction is the same in all the wire rods 2a to 2d, The direction in which the wires 2a to 2d are spiraled is also aligned in either the clockwise direction or the counterclockwise direction. Then, when the wire rods 2a to 2d are drawn into the cylindrical member 4, they contact with the outlet peripheral edge of the cylindrical member 4 at the same angle, so that all the wire rods fall into the cylindrical member 4 while falling in the same direction. Go folded. Therefore, it is considered that the non-uniformity of the arrangement of the cauterized portions 3a to 3d when the wires 2a to 2d are drawn into the cylindrical member 4 is eliminated. Therefore, even when the wire rods 2a to 2d advance to the outside of the tubular member 4 and expand, the irregular state does not occur, and the cautery portions 3a to 3d are easily arranged as designed.

(Embodiment 3)
Hereinafter, a medical ablation catheter according to a third embodiment of the present invention will be described with reference to the drawings. Since the medical ablation catheter according to the present embodiment basically has the same configuration as the medical ablation catheter according to the first embodiment, description of common parts is omitted. FIG. 5 is a cylindrical projection of the wire of the medical ablation catheter according to the third embodiment. The side view of the medical ablation catheter according to the third embodiment as viewed from the distal side is the same as that in the first embodiment as shown in FIG.

  As shown in FIG. 3, the wires 2a to 2d of the medical ablation catheter according to the third embodiment of the present invention have one apex (maximum part) projecting outward, and each apex is cauterized. Parts 3a to 3d are provided. Further, each apex is different in position in the axial direction of the cylindrical member 4, and therefore, unlike the first embodiment, each cautery portion 3 a to 3 d is in a different position in the axial direction of the cylindrical member 4 as shown in FIG. 5. Respectively. By arranging the cauterization parts 3a to 3d in this way, the ablation sites are scattered in a spiral shape, that is, the ablation sites are present at different positions in the flow direction of the renal arteries. Even if it swells, the stenosis of the renal artery is less likely to occur because the swollen sites do not overlap.

(Embodiment 4)
Hereinafter, a medical ablation catheter according to a fourth embodiment of the present invention will be described with reference to the drawings. Since the medical ablation catheter according to the fourth embodiment basically has the same configuration as the medical ablation catheter according to the first embodiment, description of common parts is omitted.

  FIG. 6 is a perspective view of the wire 2a of the medical ablation catheter according to the fourth embodiment of the present invention. As shown in FIG. 6, the wire 2a according to the fourth embodiment has vertices at two locations, and a first cautery portion 3a and a second cautery portion 3aa are provided at the respective vertices. However, the vertex formed in the wire 2a is not in the same plane, but the plane including the vertex including the first cauterized portion 3a and the plane including the vertex including the second cauterized portion 3aa are mutually A predetermined angle (45 degrees in FIG. 6) is formed. Although not shown, the same applies to the wires 2b to 2d. On the two surfaces forming an angle of 45 degrees, the first cautery part 3b and the second 3bb, the first cautery part 3c and A second 3cc, a first cautery part 3d, and a second 3dd are provided. Although it is effective to provide a plurality of cauterized portions for one wire in order to perform cauterization treatment at a plurality of locations in the renal artery, the sympathetic nerve of the renal artery extends along the length direction of the renal artery. Therefore, even if the position is different in the length direction of the renal artery, if the same position in the circumferential direction of the renal artery is cauterized, the same sympathetic nerve is cauterized in two places. If the same sympathetic nerve is cauterized at two or more places, there is a risk that the renal artery is blocked by shock. Moreover, since the sympathetic nerve is cut at one place, it is not efficient to cauterize the same sympathetic nerve at two places.

  Therefore, as described in the present embodiment, the circumferential position of the second cautery parts 3aa to 3dd in the renal artery is made to be out of phase by, for example, 45 degrees with respect to the first cautery parts 3a to 3d. Can avoid redundant cauterization of the same sympathetic nerve.

(Embodiment 5)
Hereinafter, a medical ablation catheter according to a fifth embodiment of the present invention will be described with reference to the drawings. Since the medical ablation catheter according to the fifth embodiment basically has the same configuration as the medical ablation catheter according to the first embodiment, description of common parts is omitted.

  Fig.7 (a) is a perspective view of the medical ablation catheter concerning Embodiment 5 of this invention, FIG.7 (b) is a side view for every wire of the medical ablation catheter. As shown to Fig.7 (a), the wire 2a concerning Embodiment 5 has a vertex in two places, and the 1st cauterization part 3a and 2nd 3aa are provided in each vertex. Similarly, the wire rods 2b to 2d have vertices at two locations, and the first cautery portion 3b and the second 3bb, the first cautery portion 3c and the second 3cc, A cautery portion 3d and a second 3dd are provided. In the example of FIG. 7A, the wires 2a to 2d are once returned to the vicinity of the central axis in the vicinity of the central portion and bound by the intermediate bundle 8, but the wires 2a to 2d have vertices at two places. It is sufficient that the intermediate bundle 8 is not necessarily provided.

  As shown to Fig.7 (a), among the 1st cauterization parts provided in wire 2a-2d, the 1st cauterization part 3c in the most distal side and the 1st cauterization part in the most proximal side 3a (distance A in FIG. 7) and, among the second cauterization parts provided in the wires 2a to 2d, the most distal first cauterization part 3cc and the most proximal side The distance (distance B in FIG. 7) between a certain second cautery part 3aa can be made different from each other. For example, the distance A and the distance B can be set independently from each other according to the difference in the shape of the renal artery and the difference in the ablation energy to be given.

  Of course, it is preferable that the first cautery parts 3a to 3d and the second cautery parts 3aa to 3dd are arranged at equal intervals. This is to prevent the swollen parts from overlapping each other even if the part to be ablated is swollen.

(Embodiment 6)
Hereinafter, the manufacturing method of the medical ablation catheter concerning Embodiment 6 of this invention is demonstrated using drawing. The medical ablation catheter itself can be manufactured by a generally known method, and accommodates a plurality of wires arranged in parallel, an ablation part provided on each of the wires, and the wires. The wire member is configured to be housed in the tubular member and to be advanced to the distal side outside the tubular member, and to advance to the distal side of the tubular member. It is assumed that at least a part of the portion is of a type projecting outward from the outer diameter of the cylindrical member. The present embodiment is characterized by a method for producing a wire used for a medical ablation catheter. FIG. 8 is a diagram showing a partial manufacturing process of the medical ablation catheter according to the sixth embodiment of the present invention.

  As shown to Fig.8 (a), the wire 2a is prepared first. Next, as shown in FIG. 8B, the step of bending the wire 2a so as to be convex in the first direction at the first predetermined position 2x of the wire 2a is different from the first predetermined position. The first shaping step including the step of bending the wire in a second direction different from the first direction at a predetermined position 2y of 2 is executed.

  Next, after the first shaping step, as shown in FIG. 8 (c), a second shaping step is performed in which at least a part of the wire is bent so as to protrude outward from the outer diameter of the cylindrical member. To do. In addition, as shown in FIG.8 (c), it is desirable for the crest-shaped base part of the wire 2a to be close to the axial direction of the cylindrical member 4, and to be gentle. This is because a local load is not applied to the wire 2a, and the tubular member 4 is smoothly put in and out.

  Since the wire 2a manufactured through the above steps exhibits higher elasticity than the conventional wire 2a that has not been subjected to the first shaping step, the cauterized portion 3a provided on the wire 2a is used for the renal artery. The inner wall can be securely adhered. Although there is no restriction | limiting in particular in the angle of the part which becomes convex, For example, if it is 15-85 degree | times (preferably 20-80 degree | times, More preferably, it is 25-75 degree | times), the elasticity of the wire 2a will increase further.

  After the first shaping step, it is desirable that the wire 2a is once returned to a state close to a straight line as shown in FIG. 8A in terms of improving the elasticity of the wire 2a. For example, when the wire 2a in the state shown in FIG. 8B is sandwiched between two metal rods 12 as shown in FIG. It is preferable to stretch so as to return to a shape close to. After this step, the elasticity of the wire 2a is further increased by performing the second shaping step of FIG. 8C to complete the wire 2a. When handling the wire 2a, it is preferable to heat the wire 2a to 45 to 180 ° C (preferably 65 to 160 ° C, more preferably 85 to 140 ° C). This is because the shape of the wire 2a is more easily stabilized by heating, and the elasticity can be increased.

  In addition, as shown in FIG. 8B, the first predetermined position 2x is a valley and the second predetermined position 2y is a peak opposite to the direction of the valley. By providing the direction and the second direction in opposite directions, the elasticity with respect to the direction of the valley or the peak can be further improved.

  Further, the number of the first predetermined positions 2x and the second predetermined positions 2y may be at least one for the same length of the wire 2a. It can be further increased. Thereby, a stainless steel material and a nickel titanium (Ni-Ti) alloy with a weak elastic force can be used suitably as the wire 2a.

DESCRIPTION OF SYMBOLS 1 Ablation catheter 2a, 2b, 2c, 2d Wire 2x 1st predetermined position 2y 2nd predetermined position 3a, 3b, 3c, 3d, 3aa, 3bb, 3cc, 3dd Cauterization part 4 Cylindrical member 5 Distal bound body 6 Proximal Bundling Body 7 Cylindrical Projection Surface 8 Intermediate Bundling Body 9 X-Ray Impermeable Marker 10 Fine Wire 11 Core Material 12 Metal Rod

Claims (8)

A plurality of wires arranged in parallel, a cautery portion provided on each of the wires, and a cylindrical member that accommodates the wire, and the wire can be accommodated in the cylindrical member It is comprised so that advancement to the distal side outside the said cylindrical member is possible, and at least one part among the parts which have advanced to the distal side of the said cylindrical member is outside the outer diameter of the said cylindrical member A method of manufacturing a medical ablation catheter overhanging,
Bending the wire rod in a first direction at the first predetermined position of the wire rod, and bending the wire rod in the first direction at a second predetermined position different from the first predetermined position. A first shaping step including a step of bending so as to be convex in a second direction different from
After the first shaping step, a second shaping step of bending at least a part of the wire rod to the extent that it projects outward from the outer diameter of the cylindrical member;
Only including,
After the first shaping step, before the second shaping step, the step of relieving the convex shape once attached by stretching the wire bent by the first shaping step. A method for producing a medical ablation catheter, comprising: Wherein in the step of alleviating a convex shape, manufacturing method of a medical ablation catheter of claim 1, squeezing across the wire in two metal rods. The method for producing a medical ablation catheter according to claim 1 or 2 , wherein in the step of relaxing the convex shape, the wire is stretched while heating the wire to 45 ° C or higher and 180 ° C or lower. The method for manufacturing a medical ablation catheter according to any one of claims 1 to 3 , wherein a plurality of the first predetermined position and the second predetermined position exist in the same wire. A plurality of wires arranged in parallel, a cautery portion provided on each of the wires, and a cylindrical member that accommodates the wire, and the wire can be accommodated in the cylindrical member It is comprised so that advancement to the distal side outside the said cylindrical member is possible, and at least one part among the parts which have advanced to the distal side of the said cylindrical member is outside the outer diameter of the said cylindrical member A method of manufacturing a medical ablation catheter overhanging,
Bending the wire rod in a first direction at the first predetermined position of the wire rod, and bending the wire rod in the first direction at a second predetermined position different from the first predetermined position. A first shaping step including a step of bending so as to be convex in a second direction different from
After the first shaping step, a second shaping step of bending at least a part of the wire rod to the extent that it projects outward from the outer diameter of the cylindrical member;
Including
A method for manufacturing a medical ablation catheter, wherein a plurality of the first predetermined positions and the second predetermined positions exist in the same wire. Manufacturing method of the first medical ablation catheter according to any one of claims 1 to 5 and the second direction direction are opposite directions to each other. The method for manufacturing a medical ablation catheter according to any one of claims 1 to 6, wherein in the second shaping step, the wire is provided with a portion parallel to the axial direction of the cylindrical member.   The method for manufacturing a medical ablation catheter according to any one of claims 1 to 7, wherein the wire is bent into a periodic wave shape in the first shaping step.