JP4163745B1 - Electrode catheter - Google Patents

Abstract

An object of the present invention is to provide an electrode catheter that does not cause a drift phenomenon in which the baseline potential of an electrocardiogram becomes unstable during clinical use.
A catheter main body, a control handle, a catheter tip, a plurality of ring-shaped electrodes, and a plurality of lead wires are provided; A side hole 34 is formed corresponding to the fixed position of the electrode 31, and each of the plurality of lead wires 61 is joined to the inner peripheral surface of the ring-shaped electrode 31 at the distal end portion 61 </ b> A, thereby the ring-shaped electrode 31. To the lumen through the side hole 34 formed in the tube wall of the catheter tip 30 and extends to the lumen of the catheter tip 30, the lumen of the catheter body 10, and the inner hole of the control handle 20. An insulating resin thin film 70 is formed on the surface of the metal core wire 611 (including the welded portion W) at least at the tip portion of the lead wire 61;
[Selection] Figure 4

Description

  The present invention relates to an electrode catheter in which a plurality of ring electrodes are fixed to the outer peripheral surface of the distal end portion of the catheter.

For example, electrode catheters are used as medical instruments for diagnosing or treating cardiac arrhythmias. As such an electrode catheter, one having a distal end portion (catheter distal end portion) that bends in the plane of the catheter has been introduced (see Patent Document 1).
As shown in FIG. 14, the electrode catheter includes a catheter body 110, a control handle 116, a catheter tip 114, a plurality of ring electrodes 140, a tip electrode 138, and a connector 118. In addition, a tension wire and a flexible structure for bending the catheter tip 114 in the plane are disposed inside the electrode catheter.

  15 is a cross-sectional view showing the catheter tip 114 of the electrode catheter shown in FIG. 14, in which 120 is a side hole formed in the tube wall of the catheter tip 114, and 117 is a flexible structure (cross-section). Is a rectangular plate), 130 is a lead wire, 126 and 127 are lumens, and 129 is an injection tube.

  The tip electrode 138 and the ring electrode 140 are each connected to a separate lead wire 130. These lead wires 130 are formed by coating a metal core wire with a resin. The lead wire 130 connected to the ring-shaped electrode 140 is welded to the inner peripheral surface of the ring-shaped electrode 140 at each distal end portion, and from the side hole 120 formed in the tube wall of the catheter distal end portion 114 to the lumen 126. , Extends into the lumen 126, the lumen of the catheter body 110 and the inner bore of the control handle 116 and is connected to the connector 118 at the respective rear end portions.

  Here, as a method of mounting the ring-shaped electrode 140 to which the lead wire 130 is connected to the catheter tip 114, the lead wire 130 is passed through the side hole 120 formed in the tube wall of the catheter tip 114, and then The coating resin at the distal end portion is peeled to expose the metal core wire, and the metal core wire is welded to the inner peripheral surface of the ring-shaped electrode 138. Next, the ring-shaped electrode 138 is slid on the outer periphery of the catheter distal end portion 114. A method of sliding (sliding) along the axial direction of the catheter tip 114 to a position where it can be fitted and the opening of the side hole 120 can be closed, and is fixed using polyurethane adhesive or the like at that position. (See paragraph 0029 of Patent Document 1).

As an electrode catheter for measuring a potential at a site such as a pulmonary vein of the heart, an electrode catheter having a catheter tip portion formed in a loop shape is known.
Here, the present applicant can measure the potential in almost the entire region of the catheter tip, and has at least one lumen as an electrode catheter that does not damage the inner wall of the blood vessel by the tip of the catheter tip. A main body, a control handle connected to the proximal end side of the catheter main body, a lumen connected to the distal end side of the catheter main body and communicating with at least one lumen of the catheter main body, and formed in a circular loop shape A plurality of ring-shaped electrodes are attached to the outer periphery of the catheter tip, and a spherical tip electrode is attached to the tip of the catheter tip. An electrode catheter having a diameter larger than the outer diameter of the distal end portion of the catheter has been proposed. References 2).

  16 is a cross-sectional view showing the distal end portion of the electrode catheter described in Patent Document 2, and FIG. 17 is a partially enlarged cross-sectional view (detailed view of A portion) of FIG.

  In FIG. 16, 30 is a catheter tip, 31 is a ring electrode, 32 is a tip electrode, 34 is a side hole formed in the tube wall of the catheter tip 30, 51 is a core wire having shape memory characteristics, and 61 and 62 are Lead wire. In addition, in FIG. 16, the catheter tip part 30 which is actually a loop shape is illustrated linearly.

In FIG. 17, reference numeral 611 denotes a metal core wire constituting the lead wire 61, 612 denotes a coating resin constituting the lead wire 61, W denotes a welded portion, and 351, 352, and 36 each function as an adhesive or sealant. It is a cured resin (resin cured product).
Here, the diameter of the metal core wire 611 constituting the lead wire 61 is, for example, 0.1 mm, and the thickness of the coating resin 612 made of, for example, polyamideimide resin is, for example, 10 μm.
The lead wire 61 is resistance-welded to the inner peripheral surface of the ring-shaped electrode 31 at the tip portion 61A (a part of the tip portion 61A is a welded portion W). For this welding, the coating resin 612 at the tip portion 61A of the lead wire 61 is peeled off, and the metal core wire 611 is exposed.

The cured resin 351 constitutes an adhesive layer between the catheter tip 30 (outer peripheral surface) and the ring-shaped electrode 31 (inner peripheral surface).
The cured resin 352 functions as a sealant that prevents the liquid from flowing into the lumen of the catheter tip 30 by being filled in the side hole 34.
The cured resin 351 and the cured resin 352 are formed, for example, by curing a two-component curing type epoxy resin.
The cured resin 36 is formed at both ends of the ring-shaped electrode 31 by, for example, applying an ultraviolet curable polyurethane resin and photocuring, thereby preventing the edge of the ring-shaped electrode 31 from being exposed.

As shown in FIG. 16, separate lead wires 61 are connected to the ring-shaped electrodes 31, respectively.
The lead wires 61 connected to the ring-shaped electrode 31 are welded to the inner peripheral surface of the ring-shaped electrode 31 at the metal core wire 611 of each distal end portion 61A, and are formed on the tube wall of the catheter distal end portion 30. It enters into the lumen from the side hole 34 and extends to the lumen of the distal end of the catheter, the lumen of the catheter body, and the inner hole of the control handle, and at each rear end portion, a connector attached to the proximal end of the control handle It is connected.
Further, a lead wire 62 is connected to the tip electrode 32, and the lead wire 62 extends to the lumen of the catheter tip 30, the lumen of the catheter body, and the inner hole of the control handle. It is connected to the connector attached to the base end side.

  Here, as a method of attaching the ring electrode 31 to which the lead wire 61 is connected to the catheter tip portion 30, first, the coating resin 612 at the tip portion 61A of the lead wire 61 is peeled to expose the metal core wire 611, This metal core wire 611 is resistance-welded (spot welded) to the inner peripheral surface of the ring-shaped electrode 31.

Next, a catheter tip 30 is prepared in which side holes 34 are formed corresponding to positions where the plurality of ring-shaped electrodes 31 are fixed, and each of the ring-shaped electrodes 31 on the outer peripheral surface of the catheter tip 30 is provided. For example, an adhesive made of a two-component curing type epoxy resin is applied to the region to be fixed (the region including the opening of the side hole 34).
A part of the adhesive is spread on the outer peripheral surface of the catheter tip 30 to form an adhesive layer, and the remainder of the adhesive is filled in the side holes 34 and functions as a sealant.

Next, the rear end of the lead wire 61 connected to the ring-shaped electrode 31 is inserted into the side hole 34 filled with the adhesive, and the lead wire 61 is inserted through the lumen of the catheter tip 30 and the catheter tip The ring-shaped electrode 31 is slidably fitted to the outer periphery of the section 30 and the ring-shaped electrode 31 is slid (slided) along the axial direction of the catheter tip 30 to a position where the opening of the side hole 34 can be blocked. The ring-shaped electrode 31 is adhered to the outer peripheral surface of the catheter tip 30 at the position. Thereafter, while the adhesive is not cured, the ring-shaped electrode 31 is caulked, and an ultraviolet curable polyurethane resin is applied to both ends of the ring-shaped electrode 31 and photocured to form a cured resin 36.
On the other hand, the lead wire 61 inserted through the lumen of the catheter tip 30 is passed through the lumen of the catheter body and the inner hole of the control handle, and the rear end portion of the lead wire 61 is connected to the connector.

When using the electrode catheter described in Patent Document 2 manufactured through such a process, the potential data measured by the ring-shaped electrode 31 (outer surface) is transferred to an electrocardiograph connected to the connector via a cable. Sent.
JP 2006-255401 A (paragraph 0029) Japanese Patent No. 4027411 (Claim 1)

Conventionally known electrode catheters including those described in Patent Document 1 and Patent Document 2 have a phenomenon (drift phenomenon) that the baseline potential of the electrocardiogram becomes unstable when it is used clinically.
That is, the catheter tip located inside the heart swings as the heart beats (the ring-shaped electrode fixed to the catheter tip moves). Causes the problem of being disturbed.
And such a drift phenomenon generate | occur | produced notably in the electrode catheter of patent document 2 which has the catheter front-end | tip part formed in the loop shape.

  As a result of intensive studies to investigate the cause of this drift phenomenon, it was confirmed that blood flowed into the lumen from the side hole formed at the distal end of the catheter in the electrode catheter in which the drift phenomenon occurred.

In the electrode catheter described in Patent Document 1, although the opening of the side hole 120 formed in the catheter distal end portion 114 is closed by the ring-shaped electrode 138 that is adhesively fixed so as to cover it, it is made of metal. Since the opening of the side hole 120 cannot be completely (liquid-tight) blocked by the ring-shaped electrode 138, the outer peripheral surface of the catheter tip 114 (formation surface of the adhesive layer) and the inner peripheral surface of the ring-shaped electrode 138 A gap serving as a liquid flow path is formed between them.
Further, even if such a gap is not formed between the two at the time of manufacture, since the operation of bending the catheter tip 114 is repeatedly performed at the time of use, it is flexible when the catheter tip 114 is bent. The flexible ring-shaped electrode 138 cannot follow the expansion and contraction of the flexible catheter tip 114 (tube wall), and as a result, partial peeling occurs on the bonding surface between the two, resulting in later A gap (liquid flow path) may be formed.

  In the electrode catheter described in Patent Document 2, the opening of the side hole 34 formed in the distal end portion 30 of the catheter is closed by the ring-shaped electrode 31 that is adhesively fixed so as to cover the side hole 34. A cured resin 352 is filled therein, and the ring-shaped electrode 31 is caulked, and a cured resin 36 is formed at both ends thereof. For this reason, it has been considered that blood can be prevented from flowing from the side hole 34 into the lumen of the catheter tip 30.

However, at the time of manufacturing the electrode catheter described in Patent Document 2, it is difficult to fill the side hole 34 with a very small diameter with an adhesive having a certain degree of viscosity such as epoxy resin. In some cases, a gap serving as a liquid flow path is formed in the cured resin 352.
If the amount of adhesive applied to the catheter tip 30 is increased in an attempt to reliably fill the side hole 34 with the adhesive, the adhesive may be hardened or the shaft of the catheter tip 114 may be damaged. The ring-shaped electrode 31 cannot be slid along the direction.
Further, when the electrode catheter is manufactured, the core electrode 51 in which the loop shape is memorized is inserted into the lumen after the ring-shaped electrode 31 is bonded and fixed to the outer peripheral surface in a state where the catheter tip 30 is linearly extended. In this way, the catheter tip 30 is formed into a loop shape (bending). However, since the radius of curvature of the loop is small, the flexible catheter tip 30 (tube wall) is bent during the bending. The ring-shaped electrode 31 having no flexibility cannot follow the expansion and contraction, and as a result, the space between the outer peripheral surface of the catheter tip 30 (formation surface of the adhesive layer) and the inner peripheral surface of the ring-shaped electrode 31 There may be a case where a gap is formed as a liquid flow path due to partial peeling.
In addition, when the electrode catheter is used, the catheter tip 30 moves through the sheath to the vicinity of the target site in a linearly extended state, and is restored to a loop shape when it comes out of the sheath. At the time of this restoration, partial separation occurs between the outer peripheral surface of the catheter tip 30 (formation surface of the adhesive layer) and the inner peripheral surface of the ring electrode 31 to form a gap (liquid flow path). May be.

  As described above, by attaching and fixing the ring electrode so as to cover the opening of the side hole formed at the distal end of the catheter, filling the side hole with a cured resin, and further caulking the ring electrode However, the side hole could not be completely (liquid tightly) sealed, and blood could not be prevented from flowing into the lumen.

On the other hand, at the time of manufacturing the electrode catheter, in order to electrically connect the ring-shaped electrode and the lead wire, it is necessary to weld the metal core wire of the lead wire to the inner peripheral surface of the ring-shaped electrode, Therefore, it is necessary to peel the coating resin at the tip of the lead wire to expose the metal core wire. For this reason, for example, as shown in FIG. 17, the metal core wire 611 remains exposed at the distal end portion 61 </ b> A of the lead wire 61 positioned at the lumen of the catheter distal end portion 30.
However, when blood that has flowed into the lumen of the distal end portion 30 of the catheter (or blood that has entered through the gap of the cured resin 352 filled in the side hole 34) contacts the metal core wire 611 of the lead wire 61, the blood passes through the blood. Thus, current leakage occurs between each of the plurality of ring-shaped electrodes 31, or an electric signal (current) to be input from the ring-shaped electrode 31 is input from the metal core wire 611. It is speculated that this may cause the baseline potential of the electrocardiogram to become unstable.

The present invention has been made based on the above situation.
An object of the present invention is to provide an electrode catheter that does not cause a drift phenomenon in which the baseline potential of an electrocardiogram becomes unstable when used clinically.

  As a result of diligent research to solve the above problems, an insulating resin thin film is formed on the surface of the metal core wire exposed by peeling the coating resin during welding (the metal core wire is formed of an insulating resin). By re-coating with this method, it is found that even if blood flows into the lumen from the side hole at the distal end of the catheter, the baseline potential of the electrocardiogram is stabilized and no drift phenomenon occurs, and the present invention is based on such knowledge. It came to complete.

  The electrode catheter of the present invention includes a catheter main body having at least one lumen, a control handle connected to the proximal end side of the catheter main body, and at least one of the lumens of the catheter main body connected to the distal end side of the catheter main body. A catheter tip having a lumen that communicates with each other, a plurality of ring-shaped electrodes that are spaced apart from each other on the outer peripheral surface of the catheter tip, and are connected to each of the plurality of ring-shaped electrodes. And a plurality of lead wires formed by coating a metal core with a resin; a side wall extending from the outer peripheral surface of the catheter tip to the lumen is formed in the tube wall of the catheter tip. Each of the plurality of lead wires is bonded to the inner peripheral surface of the ring-shaped electrode at the tip portion thereof. Thus, while being connected to the ring-shaped electrode, it enters the lumen of the catheter tip through a side hole formed in the tube wall of the catheter tip, and the lumen of the catheter tip and the lumen of the catheter body An insulating resin thin film is formed on at least the surface of the metal core wire and the inner peripheral surface of the ring electrode at the tip of the lead wire. It is characterized by.

  According to the electrode catheter having such a configuration, since the insulating resin thin film is formed on the surface of the metal core wire at the distal end portion of the lead wire, when the electrode catheter is used, the side hole of the catheter distal end portion extends from the lumen. Even if blood flows into contact with the tip portion, blood does not contact the metal core wire constituting the lead wire, so that current leaks between the ring electrodes or an electrical signal ( Current) is not input, and the drift phenomenon caused by this can be reliably prevented.

  In the electrode catheter of the present invention, each of the plurality of lead wires is welded to the inner peripheral surface of the ring-shaped electrode by welding a metal core wire exposed by peeling the coating resin at the distal end portion thereof. The catheter is connected to the electrode and enters the lumen of the catheter tip from a side hole formed in the tube wall of the catheter tip, and the lumen of the catheter tip, the lumen of the catheter body, and the control handle It is preferable that an insulating resin thin film is formed on the surface of the metal core wire that extends into the hole and is exposed at the time of welding at the tip portion of the lead wire.

  According to the electrode catheter having such a configuration, the metal core wire that is exposed by peeling off the coating resin at the tip end portion of the lead wire is welded to the inner peripheral surface of the ring-shaped electrode at the time of manufacture. The lead wire can be securely connected (electrically connected) to the electrode, and the insulating resin thin film is formed on the surface of the metal core wire exposed during welding (entire region including the welded portion with the ring electrode) When the electrode catheter is used, the lead wire is configured even if blood flows into the lumen from the side hole of the catheter tip and contacts the tip. Since the blood does not come into contact with the metal core wire, no current leaks between the ring-shaped electrodes, and no electrical signal (current) is input from the lead wire. The door phenomenon can be reliably prevented.

In the electrode catheter of the present invention, the insulating resin thin film is preferably composed of a vapor-deposited polymer film, and in particular, is preferably composed of at least one vapor-deposited polymer film selected from polyimide resin, polyurea resin and paraxylylene resin. preferable.
The vapor-deposited polymer film is a uniform thin film with excellent adhesion to the metal core wire, and according to the vapor-deposition polymerization method, the evaporated raw material monomer can be infiltrated into details, so that the inner peripheral surface of the ring electrode Even if the metal core wire is welded to the film, the film can be reliably formed.
The insulating resin thin film may be a resin film formed by removing the solvent from a varnish coating film containing an insulating resin and a solvent.

  In the electrode catheter of the present invention, it is preferable that the distal end portion of the catheter is formed in a loop shape. Since the catheter tip formed in a loop shape tends to allow blood to flow into the lumen due to bending during manufacture and shape change during use, in an electrode catheter having such a catheter tip, It is extremely effective to adopt a configuration in which an insulating resin thin film is formed on the surface of the metal core wire at the tip portion.

  The manufacturing method of the present invention is a method for manufacturing the electrode catheter of the present invention, wherein the surface of the metal core wire exposed at the tip end portion of the lead wire welded to the inner peripheral surface of the ring electrode is insulative. The method includes a step of forming a resin thin film.

The production method of the present invention preferably includes the following steps (1) to (4).
Furthermore, it is preferable to include the following step (5).

(1) The coating resin at the tip portion of the lead wire is peeled to expose the metal core wire, and the metal core wire is resistance-welded to the inner peripheral surface of the ring-shaped electrode. Connecting each of the plurality of lead wires.
(2) A step of masking the outer peripheral surface of the ring-shaped electrode and forming a vapor-deposited polymer film of an insulating resin on the surface of the metal core wire exposed at the tip end portion of the lead wire and the inner peripheral surface of the ring-shaped electrode.
(3) The rear end of the lead wire connected to the ring-shaped electrode is inserted into a side hole formed in the tube wall of the catheter distal end corresponding to the position where the ring-shaped electrode is fixed, While inserting the lead wire through the lumen of the catheter tip,
The ring electrode is slidably fitted to the outer periphery of the catheter tip, and the ring electrode is slid along the axial direction of the catheter tip to a position where the opening of the side hole can be blocked. And bonding the ring-shaped electrode to the outer peripheral surface of the distal end portion of the catheter at the position.
(4) A step of caulking the ring-shaped electrode bonded to the outer peripheral surface of the catheter tip.
(5) A step of applying and hardening a curable resin to both ends of the ring-shaped electrode.

According to the electrode catheter of the present invention, it is possible to prevent a drift phenomenon that has occurred when a conventionally known electrode catheter is clinically used.
The electrode catheter according to the present invention does not generate a drift phenomenon even when blood flows into the lumen at the distal end of the catheter.

<First Embodiment>
1 is a perspective view showing an embodiment of the electrode catheter of the present invention, FIG. 2 is a cross-sectional view schematically showing the internal structure of the electrode catheter shown in FIG. 1, and FIG. 3 is an electrode shown in FIG. Sectional drawing which shows the catheter front-end | tip part of a catheter, FIG. 4 is the elements on larger scale (part B detailed drawing) of FIG. 2 and 3, the loop-shaped catheter tip 30 is shown linearly. 1 to 4, the same reference numerals are used for the same or corresponding components as those shown in FIGS. 16 and 17.

  The electrode catheter 1 of this embodiment shown in FIGS. 1 to 4 includes a catheter body 10, a control handle 20 connected to the proximal end side of the catheter body 10, and a circular loop connected to the distal end side of the catheter body 10. Of the catheter tip 30 formed in a shape, a plurality (nine) of ring-shaped electrodes 31 that are spaced apart from each other on the outer peripheral surface of the catheter tip 30 and fixed using an adhesive, and the tip of the catheter tip 30 The spherical tip electrode 32 mounted on the connector, the connector 18 attached to the base end side of the control handle 20, and the metal core wire 611 are coated with resin, and each of the plurality of ring-shaped electrodes 31 and the connector 18 are electrically connected. A plurality of (9) lead wires 61 to be connected to each other and a lead wire 62 to electrically connect the tip electrode 32 and the connector 18; In the tube wall, side holes 34 extending from the outer peripheral surface of the catheter tip 30 to the lumen are formed at a plurality of locations (9 locations) corresponding to the fixing positions of the plurality of ring-shaped electrodes 31. Each of them is connected to the ring-shaped electrode 31 by resistance welding the metal core wire 611, which is exposed by peeling off the coating resin 612 at the distal end portion 61A, to the inner surface of the ring-shaped electrode 31, and the catheter. It enters the lumen of the catheter tip 30 from the side hole 34 formed in the tube wall of the tip 30, extends to the lumen of the catheter tip 30, the lumen of the catheter body 10, and the inner hole of the control handle 20, and its rear end The surface of the metal core wire 611 and the ring that are connected to the connector 18 at the portion 61B and exposed at the tip portion 61A of the lead wire 61 during welding. Insulating resin film 70 on the inner circumferential surface of the electrode 31 made of vapor-deposited polymer film is formed. That is, the metal core wire 611 (including the spot welded portion W with the ring-shaped electrode 31) at the distal end portion 61A of the lead wire 61 is recoated with an insulating resin.

  The electrode catheter 1 of this embodiment includes a catheter body 10, a control handle 20, a catheter tip 30, nine ring electrodes 31, a spherical tip electrode 32, nine lead wires 61, and a connector. 18.

  The catheter body 10 is an elongated tubular structure having one lumen, and includes a first tube 11 and a second tube 12.

The first tube 11 is required to have certain flexibility (flexibility), incompressibility in the tube axis direction, and torsional rigidity. The rotational torque from the control handle 20 can be transmitted to the catheter tip 30 by the torsional rigidity of the first tube 11.
The first tube 11 is not particularly limited, but a tube made of a resin such as polyurethane, nylon, or polyether block amide “PEBAX (registered trademark)” is braided with a stainless steel wire (blade tube). Can be mentioned.
The length of the first tube 11 is, for example, 50 to 200 cm.

The second tube 12 is a tube that constitutes the distal end portion of the catheter body 10 and has a lumen that communicates with the lumen of the first tube 11, and is provided by a deflection mechanism (a leaf spring disposed in the lumen), which will be described later. Bend.
A non-toxic resin can be used as a constituent material of the second tube 12. The second tube 12 is more flexible than the first tube 11 because it is not braided.
The length of the second tube 12 is, for example, 3 to 10 cm, and more preferably 4 to 7 cm.

  The outer diameter of the catheter body 10 (the first tube 11 and the second tube 12) is preferably 2.6 mm or less, more preferably 2.4 mm or less, and particularly preferably 2.3 to 2.4 mm. Is done.

  The inner diameter of the catheter body 10 is 1 when the outer diameter is 2.3 to 2.4 mm, for example, from the viewpoint of securing the accommodation space such as a wire and a lead wire and ensuring torsional rigidity (thickness). It is preferably about 5 to 1.7 mm.

The control handle 20 is connected to the proximal end side of the catheter body 10 (first tube 11). In FIG. 1, 21 is a grip and 22 is a knob.
By rotating the control handle 20, the rotational torque is transmitted to the catheter tip 30 via the catheter body 10.

  Further, by sliding the knob 22 to the proximal end side, the second tube 12 is bent by a later-described deflection mechanism, and the catheter distal end portion 30 is deflected accordingly.

  Therefore, by operating the control handle 20 to rotate and further deflect the catheter tip 30, the catheter tip 30 can be guided to the target site.

The catheter distal end portion 30 is a tube connected to the distal end side of the catheter main body 10 (second tube 12) and has a lumen communicating with the lumen of the catheter main body 10 (second tube 12).
Examples of the constituent material of the catheter tip 30 include a bio-acceptable resin material such as polyurethane or PEBAX (registered trademark).
The tube constituting the catheter tip 30 is formed in a substantially circular loop shape. Thereby, the inner peripheral part of the blood vessel can be simultaneously measured in the radial direction. The catheter tip 30 is not a flat circular closed loop, but a spiral loop with the tip electrode 32 at the forefront (in the present invention, the term “circular” or “elliptical” Includes those that are helical). Therefore, the inside of the blood vessel can be easily advanced toward the target site.

  Nine ring-shaped electrodes 31 are mounted on the outer peripheral surface of the catheter tip 30. A spherical tip electrode 32 is attached to the tip of the catheter tip 30.

The ring-shaped electrode 31 attached to the catheter tip 30 is made of a conductive material such as platinum, gold, iridium, or an alloy thereof.
The ring-shaped electrodes 31 are spaced apart from each other on the outer peripheral surface of the catheter tip 30 and are fixed using an adhesive. Corresponding to the fixing position of the ring-shaped electrode 31, nine side holes 34 extending from the outer peripheral surface to the lumen are formed in the tube wall of the catheter distal end portion 30.
Of course, the number of ring electrodes 31 (the number of side holes) is not limited to nine. The number of ring electrodes 31 is preferably 6 to 20, more preferably 8 to 12.

In the electrode catheter 1 of the present embodiment, a spherical tip electrode 32 is attached to the tip of a catheter tip 30 formed in a circular loop shape, whereby almost the entire region of the catheter tip 30, that is, the most A region from the ring-shaped electrode 31 on the proximal end side to the distal end to which the tip electrode 32 is attached can be used as a potential measurement region.
Moreover, since the tip electrode 32 is spherical, even if the tip electrode 32 presses or scrapes the inner wall of the blood vessel, the blood vessel is not damaged.

The diameter of the spherical tip electrode 32 is preferably 1.5 to 2.0 mm, particularly preferably 1.8 mm.
In addition, the diameter of the tip electrode 32 is preferably larger than the outer diameter of the catheter tip 30, specifically, preferably 1.05 times or more the outer diameter of the catheter tip 30, and more preferably 1 0.05 to 2.5 times.

As shown in FIG. 2, the electrode catheter 1 of this embodiment includes a deflection mechanism for deflecting the catheter tip 30.
This deflection mechanism has a pull wire 41 and a leaf spring 42.
The pull wire 41 constituting the deflection mechanism extends to the lumen of the catheter body 10. The proximal end portion 41 </ b> B of the pull wire 41 is fixed inside the control handle 20. The control handle 20 has a piston mechanism (not shown) that moves the proximal end of the catheter body 10 to the distal side relative to the pulling wire 41 by sliding the knob 22 from the state shown in FIG. Is provided. On the other hand, the distal end portion 41 </ b> A of the pull wire 41 is fixed to the distal end portion of the leaf spring 42.

  Examples of the constituent material of the pull wire 41 include stainless steel and Ni—Ti alloy. The surface of the pull wire 41 is preferably covered with PTFE “Teflon (registered trademark)” or the like. The diameter of the pull wire 41 is, for example, 0.1 to 0.5 mm.

The base end of the leaf spring 42 constituting the deflection mechanism is fixed to the distal end of the first coil tube 43.
The first coil tube 43 is formed by winding a wire having a flat or circular cross section into a coil shape, and extends to the lumen of the first tube 11 to prevent the first tube 11 from being crushed. Is functioning as

A part of the pull wire 41 (a range from the tip of the first coil tube 43 to the tip of the leaf spring 42) is surrounded by the second coil tube 44.
The base end of the second coil tube 44 is fixed to the tip of the first coil tube 43, and the tip thereof is slightly based on the tip of the leaf spring 42 (the fixing position of the tip 41A of the pull wire 41). It is fixed to the end side.

The inner diameter of the second coil tube 44 is slightly larger than the diameter of the pull wire 41, and the pull wire 41 can move (slide) in the second coil tube 44.
The second coil tube 44 is preferably made of a metal material such as stainless steel, and its outer surface is preferably covered with a non-conductive member.

The distal end portion 41A of the pull wire 41 is fixed to the distal end portion of the leaf spring 42, and the proximal end portion of the core wire 51 having shape memory characteristics is further fixed to the distal end side thereof. The core wire 51 extends along the lumen of the catheter tip 30, and the tip is fixed to the tip electrode 32 as shown in FIG. 3.
The core wire 51 stores the loop shape of the catheter tip 30 and is easily deformed (for example, deformed linearly) by applying a force, but returns to the loop shape when the force is removed.
An example of the constituent material of the core wire 51 is a Ni—Ti alloy. The ratio of Ni and Ti in the Ni—Ti alloy is preferably 54:46 to 57:43. Nitinol can be mentioned as a preferred Ni-Ti alloy.

  The deflection mechanism of the catheter tip 30 operates as follows. That is, when the operator slides the knob 22 of the control handle 20 to the distal end side, the pulling wire 41 and the catheter body 10 are moved relative to each other by a piston mechanism (not shown) in the control handle 20. The leaf spring 42 to which the distal end portion 41A is fixed is bent, and the distal end portion (second tube 12) of the catheter body 10 including the leaf spring 42 is bent, and as a result, the catheter distal end portion 30 is deflected. . Then, when the knob 22 is slid to the proximal end side and returned to the original position, the leaf spring 42 becomes linear and the catheter distal end portion 30 returns to the original direction. Of course, the deflection mechanism in the electrode catheter of the present invention is not limited to this.

  As shown in FIGS. 2 and 3, the electrode catheter 1 of the present embodiment is attached to each of a plurality (nine) of ring-shaped electrodes 31 attached to the catheter distal end portion 30 and the proximal end side of the control handle 20. A plurality of (9) lead wires 61 for electrically connecting the connector 18 are provided. The electrode catheter 1 includes a lead wire 62 that electrically connects the tip electrode 32 and the connector 18.

As shown in FIG. 4, the lead wire 61 for connecting the ring electrode 31 and the connector (18) is formed by covering a metal core wire 611 with a resin 612. An example of the coating resin 612 is a polyamideimide resin.
At the tip portion 61A of the lead wire 61, the metal core wire 611 which is exposed by peeling the coating resin 612 is resistance welded (spot welded) to the inner peripheral surface of the ring electrode 31. An insulating resin thin film 70 made of a vapor-deposited polymer film is formed on the surface of the metal core wire 611 exposed during welding (entire region of the tip including the spot welded portion W) and the inner peripheral surface of the ring-shaped electrode 31. The surface of the metal core wire 611 exposed during welding is recoated with an insulating resin.

Thus, since the metal core wire 611 exposed at the tip portion 61A of the lead wire 61 is welded to the inner peripheral surface of the ring-shaped electrode 31, the metal-to-metal bonding is ensured, and the lead wire 61 is connected to the ring-shaped electrode 31. Can be reliably connected (electrical connection).
Moreover, since the insulating resin thin film 70 is formed on the exposed surface of the metal core wire 611 (entire region of the distal end portion 61A including the spot welded portion W), blood flows into the lumen from the side hole 34 of the catheter distal end portion 30. Even if blood enters the gap between the cured resins 352 filled in the side holes 34, the blood does not come into contact with the metal core wire 611 in the tip portion 61A of the lead wire 61.
Therefore, current leakage between the ring-shaped electrodes 31 due to blood coming into contact with the metal core wire 611 and input of an electric signal (current) from the lead wire 61 do not occur, and the drift phenomenon caused by this does not occur. Can be prevented.

Here, the “vapor deposition polymer film” constituting the insulating resin thin film 70 refers to a thin film formed by a vapor deposition polymerization method.
The vapor deposition polymerization method is a method of forming a polymerized film (resin thin film) on the surface of the substrate by heating and evaporating the raw material monomer in a reduced pressure or vacuum atmosphere and reacting on the substrate.

The thickness of the insulating resin thin film made of the vapor-deposited polymer film is preferably 0.1 to 10 μm, more preferably 1 to 5 μm, and particularly preferably 1 to 3 μm.
The insulating resin thin film having such a film thickness is excellent in followability to the metal core wire combined with excellent adhesion, and does not peel even when the metal core wire is deformed.
If the film thickness is too small, the required withstand voltage (for example, 10 V · 20 msec) may not be ensured.
On the other hand, if the film thickness is excessive, it takes time to form the film, and the adhesion to the base material (metal core wire) may be reduced. Furthermore, the lead wire on which such a film is formed It is difficult to pass the distal end portion of this through the side hole at the distal end portion of the catheter.

  The resin constituting the insulating resin thin film may be the same as or different from the coating resin for the lead wire, and specifically, polyimide resin, polyurea resin, paraxylylene resin, polyamide resin, polyamideimide Examples thereof include, but are not limited to, resins, polyazomethine resins, polyurethane resins, and polyester resins. Of these, polyimide resins, polyurea resins and paraxylylene resins are preferred.

An insulating resin thin film made of a vapor-deposited polymer film has excellent adhesion to a base material (metal core wire), has no pinholes, and is excellent in film thickness uniformity.
Moreover, even if it is resin with high crystallinity (resin which is insoluble with respect to an organic solvent) which cannot be formed by the coating method, a thin film can be formed by the vapor deposition polymerization method.
In addition, in the vapor deposition polymerization method, since the raw material monomer is introduced as a gas with excellent penetration into details, the vapor deposition polymer film can be reliably formed even on the surface of the metal core wire welded to the inner peripheral surface of the small-diameter ring electrode. Can be formed.

  As shown in FIGS. 2 and 3, the lead wire 61 connected to each of the ring-shaped electrodes 31 enters the lumen of the catheter tip 30 from the side hole 34 formed in the tube wall of the catheter tip 30, The lumen of the catheter distal end 30, the lumen of the catheter body 10 (second tube 12 and first tube 11) and the inner hole of the control handle 20 extend to the proximal end of the control handle 20 at the rear end portion 61B. It is connected to a connector 18 attached to the side.

  The lead wire 61 is disposed so as to be somewhat movable in the lumen of the catheter body 10 (the second tube 12 and the first tube 11), so that even if the catheter tip 30 is deflected, the lead wire 61 is broken. There is no.

The electrode catheter 1 according to this embodiment is inserted into a main artery or vein such as a femoral artery, and then advances in a blood vessel toward a target site (for example, a pulmonary vein of the heart).
In the electrode catheter 1, the potential (data) measured by the ring-shaped electrode 31 (outer surface) is sent to an electrocardiograph connected to the connector 18 via a cable.

The electrode catheter 1 of the present embodiment shown in FIGS. 1 to 4 can be manufactured as follows.
First, as shown in FIG. 5A, the coating resin 612 is peeled off at the tip portion 61A of the lead wire 61 (for example, about 0.25 mm from the tip) to expose the metal core wire 611. Resistance welding (spot welding) is performed on the inner peripheral surface of the electrode 31.
In this way, the lead wire 61 is connected to each of the nine ring-shaped electrodes 31 to be attached to the catheter tip 30.

Next, as shown in FIG. 5B, the outer peripheral surface of the ring electrode 31 is covered with a mask M, and vapor deposition polymerization of an insulating resin is performed. Thereafter, the mask M is removed after the vapor deposition polymerization. Thereby, as shown in FIG. 5 (3), the insulating resin thin film 70 made of the vapor-deposited polymer film is formed on the surface of the metal core wire 611 exposed at the tip portion 61 A of the lead wire 61 and the inner peripheral surface of the ring-shaped electrode 31. It is formed.
In the present invention, it is sufficient that the insulating resin thin film 70 is formed on the surface of the metal core wire 611 (including the spot welded portion W with the ring-shaped electrode 31) in the tip portion 61A. Although it is not essential to form the insulating resin thin film 70 on the peripheral surface, the presence of the insulating resin (organic substance) on the inner peripheral surface of the ring-shaped electrode 31 makes it possible to adhere to the outer peripheral surface of the catheter tip 30. It is preferable because improvement of the above can be achieved.
In this way, for each of the nine ring-shaped electrodes 31 to be attached to the catheter distal end portion 30, the inner peripheral surface and the surface of the metal core wire 611 at the distal end portion 61A of the lead wire 61 connected thereto are insulated. A resin thin film 70 is formed.

  In the vapor deposition polymerization method for forming the insulating resin thin film 70, the ring-shaped electrode 31 to which the lead wire 16 is connected by the above-described process (welding) is placed in the reaction chamber (deposition chamber) of the vapor deposition polymerization apparatus to react. The inside of the chamber (deposition chamber) is a reduced pressure atmosphere or a vacuum atmosphere, the raw material monomer heated to a predetermined temperature is introduced into the chamber, and the evaporated raw material monomer is exposed to the exposed surface of the metal core wire 611 and the inner periphery of the ring electrode 31 The polymerization reaction is performed in contact with the surface.

  Here, in order to form a vapor deposition polymer film (insulating resin thin film 70) made of polyimide resin, aromatic tetracarboxylic dianhydride and aromatic diamine are used as raw material monomers, and the surface of metal core wire 611 and a ring shape are used. A polyamic acid thin film is formed by reacting these raw material monomers on the inner peripheral surface of the electrode 31, and the thin film is heated to carry out a dehydration ring-closing reaction (imidization) of the polyamic acid.

Examples of the “aromatic tetracarboxylic dianhydride” used to obtain the polyamic acid include pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, diphenyl ether tetracarboxylic acid Examples thereof include dianhydrides, benzophenone tetracarboxylic dianhydrides, 2,3,6,7-naphthalene tetracarboxylic dianhydrides, and among these, pyromellitic dianhydride is preferable.
In the case of using pyromellitic dianhydride, the heating temperature for evaporating it is preferably 180-240 ° C, more preferably 200-240 ° C.

Examples of the “aromatic diamine” used to obtain the polyamic acid include 4,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylethane, 4,4′-diaminodiphenylpropane, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfide, m-phenylenediamine, p-phenylenediamine, m-toluylenediamine, p-toluylenediamine, benzidine, 1,5-diaminonaphthalene, etc. Of these, 4,4′-diaminodiphenyl ether is preferred.
In the case of using 4,4′-diaminodiphenyl ether, the heating temperature for evaporating it is preferably, for example, 180 to 240 ° C., more preferably 180 to 200 ° C.

  Furthermore, the heating temperature for carrying out the dehydration ring-closing reaction of the polyamic acid obtained by the reaction of pyromellitic dianhydride and 4,4'-diaminodiphenyl ether is, for example, 250 to 300 ° C.

  In order to form a vapor-deposited polymer film (insulating resin thin film 70) made of polyurea resin, aromatic diamine and aromatic diisocyanate are used as raw material monomers, and the surface of the metal core wire 611 and the inner peripheral surface of the ring electrode 31 are used. A thin film of polyurea resin is formed by reacting these raw material monomers.

Examples of the “aromatic diamine” used to obtain the polyurea resin include 4,4′-diaminodiphenylmethane, 1,4-phenylenediamine, 4,4′-diaminodiphenyl ether, 2,2-diaminodiphenyl, and hexafluoropropane. Among them, 4,4′-diaminodiphenylmethane is preferable.
In the case of using 4,4′-diaminodiphenylmethane, the heating temperature for evaporating it is, for example, 60 to 130 ° C.

Examples of the “aromatic diisocyanate” used to obtain the polyurea resin include 4,4′-diphenylmethane diisocyanate, toluene diisocyanate, P-phenylene diisocyanate, n-phenylene diisocyanate, and of these, 4 4'-diphenylmethane diisocyanate is preferred.
In the case of using 4,4′-diphenylmethane diisocyanate, the heating temperature for evaporating it is, for example, 60 to 130 ° C.

FIG. 6 is a schematic view schematically showing an example of a vapor deposition polymerization apparatus.
This vapor deposition polymerization apparatus 80 is provided with raw material monomer heating chambers 81 and 82, a reaction chamber 83, and an exhaust means (not shown) for reducing the pressure in the reaction chamber 83 to a reduced pressure or vacuum atmosphere.
The heating chamber 81 is charged with the first monomer m1 (for example, pyromellitic dianhydride), and the heating chamber 82 is charged with the second monomer m2 (for example, 4,4′-diaminodiphenyl ether). Each is heated to a predetermined temperature by a heater (not shown).
The first monomer heated in the heating chamber 81 is placed in the reaction chamber 83 in which the object to be processed S (ring-shaped electrode 31 to which the lead wire 16 is connected) is placed in the reaction chamber 83 and is in a reduced pressure atmosphere or a vacuum atmosphere. And the second monomer heated in the heating chamber 82, the first surface is formed on the surface of the workpiece S (the surface of the metal core wire 611 and the inner peripheral surface of the ring electrode 31) disposed in the chamber. A polymerization reaction (gas phase reaction) between the monomer and the second monomer is performed. As a result, a polymer thin film (for example, a polyamic acid thin film) is formed on the surface of the workpiece S.
When a polyimide thin film is formed, the formed polyamic acid thin film is heated in the reaction chamber 83 to be imidized.

  In the case where a vapor-deposited polymer film made of paraxylylene resin is formed as the insulating resin thin film 70, examples of the paraxylylene resin include polymers represented by the following general formula. The basic structure and manufacturing method of paraxylylene resin are disclosed in US Pat. No. 3,379,803 and Japanese Examined Patent Publication No. 52-37479.

(Wherein R ¹ , R ² , R ³ and R ⁴ each represent hydrogen, chlorine, bromine, fluorine, an alkyl group or an amino group, and R ⁵ and R ⁶ each represent hydrogen or fluorine. n is an integer of 5000 or more.)

  Of these, polyparaxylylene, poly (monochloroparaxylylene), poly (dichloroparaxylylene), poly (tetrachloroparaxylylene), poly (monofluoroparaxylylene), poly (monoethylparaxylylene) Etc.) are preferred.

  In order to form a vapor-deposited polymer film (insulating resin thin film 70) made of paraxylylene-based resin, a first step of vaporizing diparaxylylene (dimer) as a raw material, and diradical paraxylylene by thermally decomposing the vaporized diparaxylylene. It is preferable to employ a vapor deposition polymerization method including a second step of generating len and a third step of forming a thin film on the surface of the object to be processed (the surface of the metal core wire 611 and the inner peripheral surface of the ring-shaped electrode 31). .

FIG. 7 is a schematic view schematically showing a vapor deposition polymerization apparatus suitable for forming a vapor deposition polymerization film made of a paraxylylene resin.
The vapor deposition polymerization apparatus 85 includes a vaporization chamber 86 in which the first step is performed, a thermal decomposition chamber 87 in which the second step is performed, and a vapor deposition chamber 88 in which the third process is performed by placing an object to be processed. I have. Reference numeral 89 denotes an attached cooling cylinder.
Here, the heating temperature in the first step (vaporization chamber 86) is preferably 170 ° C. or lower, and the degree of vacuum is preferably 135 pa or lower. Moreover, it is preferable that the temperature in a 2nd process (pyrolysis chamber 87) is 680 degrees C or less, and a vacuum degree is 70 pa or less. Moreover, it is preferable that the temperature in a 3rd process (deposition chamber) is 35 degrees C or less, and a vacuum degree is 15 pa or less.

Next, as shown in FIG. 8, a catheter tip 30 (tubular structure) having a side hole 34 extending from the outer peripheral surface to the lumen is prepared.
In addition, the side hole 34 shown by FIG. 8 is located in the front end side among the side holes formed in nine places corresponding to the position where a ring-shaped electrode is fixed.

Next, as shown in FIG. 9 (1), the lead wire 61 connected to the ring-shaped electrode 31 is passed through the side hole 34 and inserted into the lumen of the catheter tip 30, and the outer periphery of the catheter tip 30. For example, an adhesive 35 made of a two-component curable epoxy resin is applied to the area where the ring-shaped electrode is fixed on the surface. A part of the adhesive 35 is spread on the outer peripheral surface of the catheter tip 30 to form an adhesive layer, and the remaining part of the adhesive 35 is filled in the side hole 34 through which the lead wire 61 is passed. Functions as a sealant.
Next, as shown in FIG. 9 (2), the ring-shaped electrode 31 is slidably fitted to the catheter distal end 30 from the distal end side (the outer peripheral surface of the catheter distal end 30 and the inner ring of the ring-shaped electrode 31). The ring-shaped electrode 31 is slid along the axial direction of the catheter tip 30 to a position where the opening of the side hole 34 can be closed. At this position, the ring-shaped electrode 31 is bonded (temporarily attached) to the outer peripheral surface of the catheter tip 30 (formation surface of the adhesive layer).
Next, as shown in FIG. 9 (3), the ring-shaped electrode 31 is crimped (pressed inward in the radial direction of the ring) before the adhesive is cured. As a result, as shown in FIG. 9 (4), the step at both ends of the ring-shaped electrode 31 (step with respect to the outer peripheral surface of the catheter tip 30) can be lowered, and the ring-shaped electrode with respect to the catheter tip 30. The adhesion of 31 can be improved.
A part of the adhesive 35 spread on the outer peripheral surface of the catheter tip 30 is cured with time to become a cured resin 351 (adhesive layer), and the adhesive filled in the side hole 34. The remainder of 35 is cured with time to become a cured resin 352 (sealing agent).
Next, an ultraviolet curable polyurethane resin is applied to both ends of the ring electrode 31 and photocured to form a cured resin 36 as shown in FIG.
On the other hand, the lead wire 61 inserted through the lumen of the catheter tip 30 is passed through the lumen of the catheter body 10 and the inner hole of the control handle 20, and the rear end portion 61 B of the lead wire 61 is connected to the connector 18.

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to these, A various change is possible.
For example, the catheter tip portion does not need to be formed in a loop shape, and may be a straight shape or a gently curved shape (for example, a shape as shown in FIG. 14).
Moreover, the insulating resin thin film may not be made of a vapor deposition polymer film, and may be formed by another method (for example, a coating method).
Examples of suitable insulating resin thin films formed by methods other than vapor deposition polymerization include a resin film formed using a varnish (insulating film varnish) containing an insulating resin and a solvent. This resin film is coated with a varnish on the surface of the metal core wire exposed during welding (the entire tip including the spot weld), and the solvent is removed from the formed coating (insulating if necessary) It can be formed by curing the resin).
Examples of the insulating resin constituting the varnish include the resins described above as constituting the vapor-deposited polymer film. Further, the solvent constituting the varnish is not particularly limited as long as it is a volatile solvent capable of dissolving the contained resin, and examples thereof include N-methyl-2-pyrrolidone (NMP). it can.
The film thickness of the resin film (insulating resin thin film) formed using varnish is preferably 30 μm or less.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

<Example 1>
The coating resin was peeled off at the tip portion (about 0.25 mm from the tip) of the lead wire (diameter = 0.1 mm, resin film thickness = 10 μm) formed by coating the metal core wire with polyamide-imide resin to expose the metal core wire. . Next, the metal core wire exposed at the tip portion of the lead wire was resistance-welded to the inner peripheral surface of a ring-shaped electrode (outer diameter = 1.3 mm, inner diameter = 1.2 mm) made of platinum alloy.
As described above, nine ring electrodes to which lead wires were connected as shown in FIG.

Next, nine ring electrodes to which lead wires are connected are placed in a reaction chamber of a vapor deposition polymerization apparatus with the outer peripheral surface masked, and pyromellitic acid heated to a predetermined temperature in the reaction chamber. A dianhydride (first monomer) and 4,4′-diaminodiphenyl ether (second monomer) were introduced, and the surface of the metal core wire at the tip of the lead wire and the inner peripheral surface of the ring electrode were A polyamic acid thin film was formed by carrying out a polymerization reaction (gas phase reaction) between the first monomer and the second monomer. Here, the heating temperature of the first monomer was 220 ° C., the heating temperature of the second monomer was 190 ° C., and the pressure (degree of vacuum) in the reaction chamber was 0.5 Pa.
Next, by heating the formed polyamic acid thin film at 275 ° C., a polyhydric acid dehydration ring-closing reaction is performed, and the film thickness is formed on the surface of the metal core wire at the tip of the lead wire and the inner peripheral surface of the ring electrode An insulating resin thin film made of a vapor-deposited polymer film of polyimide resin having a thickness of 10 μm was formed.
As described above, as shown in FIG. 5 (3), a ring-like electrode to which a lead wire is connected, and an insulating resin thin film is formed on the inner peripheral surface and the surface of the metal core wire at the tip of the lead wire. Nine pieces were formed by forming.

Next, a ring-shaped electrode as shown in FIG. 5 (3) is bonded (temporarily attached) to the outer peripheral surface of the catheter tip using an adhesive made of a two-component curable epoxy resin, and then this ring The electrode was fixed by caulking, and an ultraviolet curable polyurethane resin was applied to both ends of the fixed ring electrode and photocured.
As a result, the insulating resin thin film formed on the surface of the metal core wire and the inner peripheral surface of the ring electrode at the tip end portion of the lead wire has the form shown in FIGS. An electrode catheter of the present invention comprising a membrane was produced.

<Example 2>
The ring-shaped electrode connected to the lead wire is subjected to the vapor deposition polymerization shown below, and an insulating layer made of a polyurea resin vapor-deposited polymer film is formed on the surface of the metal core wire and the inner peripheral surface of the ring-shaped electrode at the tip of the lead wire. The electrode catheter of the present invention was manufactured in the same manner as in Example 1 except that the conductive resin thin film was formed.

(Vapor deposition polymerization)
Nine ring electrodes to which lead wires are connected are placed in the reaction chamber of the vapor deposition polymerization apparatus while masking the outer peripheral surface of each, and 4,4′-diamino heated to a predetermined temperature in the reaction chamber. Diphenylmethane (first monomer) and 4,4′-diphenylmethane diisocyanate (second monomer) are introduced, and the first surface of the metal core wire at the tip of the lead wire and the inner peripheral surface of the ring-shaped electrode A polymerization reaction (gas phase reaction) between the monomer and the second monomer was performed to form a polyurea thin film having a thickness of 10 μm.

<Example 3>
The ring electrode connected to the lead wire is subjected to the vapor deposition polymerization shown below to insulate the surface of the metal core wire at the tip of the lead wire and the inner peripheral surface of the ring electrode from a vapor deposited polymer film of paraxylylene resin. The electrode catheter of the present invention was manufactured in the same manner as in Example 1 except that the conductive resin thin film was formed.

(Vapor deposition polymerization)
Using a vapor deposition polymerization apparatus having a vaporization chamber, a pyrolysis chamber, a vapor deposition chamber, and a cooling cylinder, nine ring electrodes connected to lead wires are masked on the outer peripheral surfaces of the vapor deposition polymerization apparatus. Arranged.
On the other hand, di (monochloroparaxylylene) is vaporized under the conditions of a temperature of 150 ° C. and a pressure (degree of vacuum) of 100 Pa in the vaporizing chamber, and under the conditions of a temperature of 680 ° C. and a pressure (degree of vacuum) of 60 Pa in the pyrolysis chamber The vaporized di (monochloroparaxylylene) is pyrolyzed to produce a diradical (monochloroparaxylylene), and the metal at the tip of the lead wire is subjected to a temperature of 30 ° C. and a pressure (degree of vacuum) of 10 Pa in the vapor deposition chamber. A vapor deposition polymer film of poly (monochloroparaxylylene) having a thickness of 10 μm was formed on the surface of the core wire and the inner peripheral surface of the ring electrode.

<Comparative Example 1>
Example 1 except that vapor deposition polymerization was not performed on the ring electrode to which the lead wire was connected, and the insulating resin thin film was not formed on the surface of the metal core wire and the inner peripheral surface of the ring electrode at the tip of the lead wire. In the same manner, a comparative electrode catheter was manufactured.

<Experimental example>
For each of the electrode catheters manufactured in Examples 1 to 3 and Comparative Example 1, in order to reproduce the oscillation (displacement of the ring-shaped electrode) of the distal end of the catheter accompanying the heartbeat when used clinically, the catheter The tip portion was periodically swung in physiological saline, and the baseline potential of the electrocardiogram was measured. Here, the rocking width was 20 mm, and the rocking cycle was 2 reciprocations / second. Further, the catheter tip was immersed in physiological saline one minute before the start of swinging. The results are shown in FIGS. 10 to 13, the horizontal axis represents time, and the vertical axis represents the potential difference between the electrodes.

As shown in FIGS. 10 to 12, the baseline potential of the electrocardiogram measured by the electrode catheters obtained in Examples 1 to 3 shows no disturbance due to oscillation, and the baseline potential is stable. Yes.
On the other hand, as shown in FIG. 13, the disturbance due to the oscillation is noticeably observed in the baseline potential of the electrocardiogram measured by the electrode catheter obtained in Comparative Example 1.

It is a perspective view which shows one Embodiment of the electrode catheter of this invention. It is sectional drawing which shows typically the internal structure of the electrode catheter shown in FIG. It is sectional drawing which shows the catheter front-end | tip part of the electrode catheter shown in FIG. FIG. 4 is a partial enlarged cross-sectional view (part B detail view) of FIG. 3. It is a schematic diagram for demonstrating the manufacturing process of the electrode catheter of this invention. It is the schematic which shows an example of a vapor deposition polymerization apparatus typically. It is the schematic which shows typically the other example of a vapor deposition polymerization apparatus. It is a schematic diagram for demonstrating the manufacturing process of the electrode catheter of this invention. It is a schematic diagram for demonstrating the manufacturing process of the electrode catheter of this invention. 2 is an electrocardiogram measured by the electrode catheter obtained in Example 1. FIG. 6 is an electrocardiogram measured by the electrode catheter obtained in Example 2. FIG. 6 is an electrocardiogram measured by an electrode catheter obtained in Example 3. FIG. 6 is an electrocardiogram measured by the electrode catheter obtained in Comparative Example 1. FIG. It is a perspective view which shows one Embodiment of the conventional electrode catheter. It is sectional drawing which shows the catheter front-end | tip part of the electrode catheter shown in FIG. It is sectional drawing which shows the catheter front-end | tip part of the conventional electrode catheter. FIG. 17 is a partial enlarged cross-sectional view (part A detail view) of FIG. 16.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrode catheter 10 Catheter main body 11 1st tube 12 2nd tube 18 Connector 20 Control handle 21 Grip 22 Knob 30 Catheter tip part 31 Ring-shaped electrode 32 Tip electrode 34 Side hole 35 Adhesive 351 Cured resin 352 Cured resin 36 Cured Resin 41 Tension wire 42 Leaf spring 43 First coil tube 44 Second coil tube 51 Core wire 61 Lead wire 611 Metal core wire 612 Coating resin 61A Lead wire tip portion 61B Lead wire trailing end portion 62 Lead wire W Spot welded portion 70 insulating resin thin film 80 vapor deposition polymerization apparatus 81 heating chamber 82 heating chamber 83 reaction chamber 85 vapor deposition polymerization apparatus 86 vaporization chamber 87 pyrolysis chamber 88 vapor deposition chamber 89 cooling cylinder

Claims (8)

A catheter body having at least one lumen;
A control handle connected to the proximal side of the catheter body;
A catheter tip having a lumen connected to the distal end of the catheter body and communicating with at least one of the lumens of the catheter body;
A plurality of ring-shaped electrodes that are spaced apart and fixed using an adhesive on the outer peripheral surface of the catheter tip, and
A plurality of lead wires connected to each of the plurality of ring-shaped electrodes and made of resin-coated metal core wires;
In the tube wall of the catheter tip, a side hole extending from the outer peripheral surface of the catheter tip to the lumen is formed corresponding to the fixing position of the ring-shaped electrode,
Each of the plurality of lead wires is connected to the ring-shaped electrode by welding a metal core wire exposed by peeling off the coating resin at the tip thereof to the inner peripheral surface of the ring-shaped electrode. The catheter tip portion enters the lumen of the catheter tip portion from the side hole formed in the tube wall of the catheter tip portion, and extends to the lumen of the catheter tip portion, the lumen of the catheter body, and the inner hole of the control handle,
An insulating resin thin film is formed at least on the surface of the metal core wire exposed during welding at the tip portion of the lead wire and the surface of the joint portion with the inner peripheral surface of the ring electrode. Electrode catheter. The electrode catheter according to claim 1, wherein the insulating resin thin film is a vapor-deposited polymer film. 2. The electrode catheter according to claim 1, wherein the insulating resin thin film is made of at least one vapor deposition polymer film selected from polyimide resin, polyurea resin, and paraxylylene resin. The electrode catheter according to claim 1, wherein the insulating resin thin film is a resin film formed by removing the solvent from a coating film of a varnish containing an insulating resin and a solvent. The electrode catheter according to any one of claims 1 to 4 , wherein the distal end portion of the catheter is formed in a loop shape. A method for producing the electrode catheter according to any one of claims 1 to 5 ,
A method for producing an electrode catheter, comprising a step of forming an insulating resin thin film on a surface of a metal core wire exposed at a tip portion of the lead wire welded to an inner peripheral surface of the ring electrode. A method for producing the electrode catheter according to any one of claims 1 to 5 ,
The plurality of leads are attached to each of the plurality of ring-shaped electrodes by peeling the coating resin at the tip portion of the lead wire to expose the metal core wire and resistance-welding the metal core wire to the inner peripheral surface of the ring-shaped electrode. Connecting each of the wires;
Masking the outer peripheral surface of the ring-shaped electrode, and forming a vapor-deposited polymer film of an insulating resin on the surface of the metal core wire exposed at the tip portion of the lead wire and the inner peripheral surface of the ring-shaped electrode;
The rear end of the lead wire connected to the ring electrode is inserted into a side hole formed in the tube wall of the catheter tip corresponding to the position where the ring electrode is fixed, and the catheter tip The lead wire is inserted through the lumen of
The ring electrode is slidably fitted to the outer periphery of the catheter tip, and the ring electrode is slid along the axial direction of the catheter tip to a position where the opening of the side hole can be blocked. And bonding the ring-shaped electrode to the outer peripheral surface of the catheter tip at the position;
Caulking the ring-shaped electrode adhered to the outer peripheral surface of the catheter tip, and
The manufacturing method of the electrode catheter characterized by including. Furthermore, the manufacturing method of the electrode catheter of Claim 7 including the process of apply | coating and hardening a curable resin to the both ends of the said ring-shaped electrode.

Images