JP2021146031A - Balloon catheter - Google Patents

Abstract

To provide a balloon catheter that easily warms a surface of a balloon and its vicinity.SOLUTION: A balloon catheter 1 has a shaft 2 having a distal end and a proximal end, a balloon 10 provided in the distal part of the shaft 2, a first electrode part 21 provided inside the balloon 10 on the shaft 2, a long flexible base material 30 provided inside the balloon 10 and outside the first electrode part 21, and a second electrode part 22 which is provided on the flexible base material 30, can move inside the balloon 10 in a predetermined trajectory, and is energized with a high-frequency current to and from the first electrode part 21.SELECTED DRAWING: Figure 1

Description

The present invention relates to a balloon catheter, specifically a balloon catheter capable of cauterizing living tissue.

In pulmonary vein isolation for the treatment of atrial fibrillation, a catheter with a balloon (ablation catheter) is used. For example, a balloon of a balloon catheter is placed in the pulmonary vein opening, a mixed solution of physiological saline and a contrast agent is injected into the balloon to inflate the balloon, and then the balloon is brought into close contact with the pulmonary vein opening, and then the balloon is used. By heating the mixed solution inside, the tissue of the pulmonary vein opening is heated and cauterized. For example, in Patent Document 1, a high-frequency energizing electrode for heating the inside of the balloon is coiled around an inner cylinder shaft at the center of the balloon inside the balloon of a high-frequency heating balloon catheter. It is disclosed that it has been done. Patent Document 1 also discloses that a vibration generator that gives vibration to the inside of a balloon is installed in the vicinity of the tip of the balloon catheter.

Japanese Unexamined Patent Publication No. 2013-132479

In the catheter described in Patent Document 1, the surface of the balloon near the biological tissue to be cauterized and its vicinity are less likely to be warmed than the vicinity of the shaft, and there is room for improvement from the viewpoint of efficient cauterization. Therefore, an object of the present invention is to provide a balloon catheter that easily warms the surface of a balloon or its vicinity.

One embodiment of the balloon catheter of the present invention that has achieved the above object is a shaft having a distal end and a proximal end, a balloon provided at the distal portion of the shaft, and a shaft inside the balloon. A first electrode portion provided on the balloon, a long flexible base material provided inside the balloon and outside the first electrode portion, and a balloon provided on the flexible base material. It has a gist in that it has a second electrode portion that can move in a predetermined locus and is energized with a high-frequency current from the first electrode portion. According to the balloon catheter, the position of the second electrode portion provided on the flexible base material is moved inside the balloon as the operator deforms the flexible base material such as bending and twisting. Therefore, the portion of the internal fluid of the balloon that is separated from the shaft can be heated. As a result, the surface of the balloon and its vicinity can be easily warmed, and the biological tissue can be efficiently cauterized. Further, since a high-frequency current is applied between the first electrode portion and the second electrode portion provided inside the balloon, cauterization is possible without arranging a counter electrode on the patient's body surface. It can also reduce the risk of electric shock and burns.

In the balloon catheter, the predetermined locus preferably includes a locus that moves in the radial direction inside the balloon.

In the balloon catheter, the flexible base material is formed in a band shape having a first surface and a second surface, and is arranged so that the first surface faces the shaft side and the second surface faces the balloon side. It is preferable that the electrode portion 2 is arranged on at least one of the first surface side and the second surface side.

In the balloon catheter, it is preferable that the second electrode portion is arranged on the first surface side and not on the second surface side.

In the balloon catheter, it is preferable that the second electrode portion is arranged on the second surface side and not on the first surface side.

It is preferred that the balloon catheter is further provided with a pusher that is fixed to a flexible substrate and slidable with respect to the shaft.

In the above balloon catheter, it is preferable that the flexible base material is curved inside the balloon and the second electrode portion is formed at a position including the outer end of the flexible base material at the time of maximum bending. ..

A plurality of flexible base materials are provided in the balloon catheter, the plurality of flexible base materials are arranged at different positions in the circumferential direction of the shaft, and the second electrode portion has a plurality of flexible base materials. It is preferable that each is arranged on the material.

It is preferable that the balloon catheter is further provided with a temperature detection unit on a flexible base material.

The balloon catheter is provided with a plurality of first electrode portions, and the plurality of first electrode portions are arranged at different positions in the longitudinal direction of the shaft, and the one first electrode portion and the second electrode portion are provided. The value of the high-frequency current between the portions is preferably larger than the value of the high-frequency current between the other first electrode portion and the second electrode portion.

It is preferable that the balloon catheter is further provided with a potential measurement electrode portion for measuring the internal potential on the outside of the balloon.

It is preferable that the balloon catheter is further provided with an outer temperature detection unit on the outside of the balloon.

The balloon catheter further has a control unit that controls the value of the current flowing through the second electrode unit, and the control unit is closest to the outer temperature detection unit according to the temperature detected by the outer temperature detection unit. It is preferable to control the value of the current flowing through the arranged second electrode portion.

It is preferable that the balloon catheter is further provided with an inner temperature detection unit on the shaft.

According to the balloon catheter, the position of the second electrode portion provided on the flexible base material is moved inside the balloon as the operator deforms the flexible base material such as bending and twisting. Therefore, the portion of the internal fluid of the balloon that is separated from the shaft can be heated. As a result, the surface of the balloon and its vicinity can be easily warmed, and the biological tissue can be efficiently cauterized. Further, since a high-frequency current is applied between the first electrode portion and the second electrode portion provided inside the balloon, cauterization is possible without arranging a counter electrode on the patient's body surface. It can also reduce the risk of electric shock and burns.

A side sectional view of a balloon catheter according to an embodiment of the present invention is shown, and a state in which a flexible base material is curved is shown. A side sectional view of the balloon catheter shown in FIG. 1 is shown, and a state in which a flexible base material is stretched is shown. A side sectional view showing a modified example of the balloon catheter shown in FIG. 1 is shown. A side sectional view showing another modification of the balloon catheter shown in FIG. 1 is shown. The VV cross-sectional view of the balloon catheter shown in FIG. 4 is shown. A side sectional view showing still another modification of the balloon catheter shown in FIG. 1 is shown. A side sectional view showing still another modification of the balloon catheter shown in FIG. 1 is shown.

Hereinafter, the present invention will be described in more detail based on the following embodiments. In addition, it is of course possible to carry out, and all of them are included in the technical scope of the present invention. In each drawing, hatching, member reference numerals, and the like may be omitted for convenience, but in such cases, the specification and other drawings shall be referred to. In addition, the dimensions of various members in the drawings may differ from the actual dimensions because priority is given to contributing to the understanding of the features of the present invention.

One embodiment of the balloon catheter of the present invention includes a shaft having a distal end and a proximal end, a balloon provided at the distal portion of the shaft, and a first inside the balloon that is provided on the shaft. The electrode portion of the balloon, a long flexible base material provided inside the balloon and outside the first electrode portion, and a flexible base material provided on the flexible base material, and the inside of the balloon is provided with a predetermined trajectory. It has a second electrode portion that is movable and is energized with a high-frequency current from the first electrode portion. According to the balloon catheter, the position of the second electrode portion provided on the flexible base material is moved inside the balloon as the operator deforms the flexible base material such as bending and twisting. Therefore, the portion of the internal fluid of the balloon that is separated from the shaft can be heated. As a result, the surface of the balloon and its vicinity can be easily warmed, and the biological tissue can be efficiently cauterized. Further, since a high-frequency current is applied between the first electrode portion and the second electrode portion provided inside the balloon, cauterization is possible without arranging a counter electrode on the patient's body surface. It can also reduce the risk of electric shock and burns.

An example of the use of a balloon catheter is pulmonary vein isolation, which is one of the treatments for atrial fibrillation. In pulmonary vein isolation, a balloon catheter is used to heat and cauterize the pulmonary vein opening by bringing a balloon containing heated fluid into contact with the pulmonary vein opening, which is an abnormality that causes atrial fibrillation. The electrical path can be blocked. In the following, the fluid supplied to the inside of the balloon may be simply referred to as an internal fluid.

The configuration of the balloon catheter will be described with reference to FIGS. 1 and 2. 1 to 2 show a side sectional view of a balloon catheter according to an embodiment of the present invention. FIG. 1 shows a curved state of a flexible base material, and FIG. 2 shows a stretched flexible base material. Shows the state. 1 and 2 show a configuration example of an over-the-wire balloon catheter in which a wire is inserted from the distal side to the proximal side of the shaft. The balloon catheter 1 has a shaft 2 and a balloon 10.

The shaft 2 has a distal end and a proximal end. A balloon 10 is provided at the distal portion of the shaft 2. A fluid feeder 5 such as a syringe for supplying a fluid to the inside of the balloon 10 is provided in the proximal portion of the shaft 2. In the present invention, the distal side of the balloon catheter 1 or the shaft 2 refers to the distal end side of the shaft 2 in the longitudinal direction (in other words, the longitudinal axis direction of the shaft 2) and the treatment target side. The proximal side of the balloon catheter 1 or the shaft 2 is the proximal side of the shaft 2 in the longitudinal direction and refers to the hand side of the user (operator). Unless otherwise specified in the present invention, the inside and outside of the shaft 2 or the balloon 10 refer to the inside and outside of the shaft 2 in the radial direction, and the inside of the shaft 2 in the radial direction means the length of the shaft 2. Refers to the side near the center of the axis.

The balloon catheter 1 is configured such that a fluid is supplied from the fluid feeder 5 to the inside of the balloon 10 through the shaft 2. By supplying a fluid inside the balloon 10, the balloon 10 can be expanded. On the other hand, the balloon 10 can be contracted by discharging the fluid from the inside of the balloon 10. Although not shown, the fluid feeder 5 may include at least one of a heater for heating the fluid and a cooler for cooling the fluid. The temperature of the fluid supplied from the fluid feeder 5 can be set and controlled as needed.

The shaft 2 is usually provided with a flow path for a fluid supplied into the balloon 10 and an insertion passage (not shown) for a wire that guides the progress of the shaft 2. In order to improve the flow of the fluid, it is preferable that the flow path of the fluid extends in the longitudinal direction of the shaft 2. The shaft 2 may have a coaxial structure composed of at least a double tube, or may have a multi-lumen structure having a plurality of lumens.

In FIG. 1, the shaft 2 is composed of an inner pipe 3 and an outer pipe 4. The lumen of the inner tube 3 functions as a wire insertion passage. The space between the inner tube 3 and the outer tube 4 functions as a flow path for the fluid supplied into the balloon 10. At the distal portion of the shaft 2, the inner tube 3 extends from the distal end of the outer tube 4 and penetrates the balloon 10 in the longitudinal direction. As a result, the distal portion of the balloon 10 can be fixed to the inner tube 3, and the proximal portion of the balloon 10 can be fixed to the outer tube 4.

In FIG. 1, the proximal portion of the outer pipe 4 of the shaft 2 is bifurcated, the fluid feeder 5 is connected to one of the branched sides, and the other side extends in the longitudinal direction. Although not shown, the shaft 2 and the fluid feeder 5 may be connected via a connecting tube or a joint. A wire can be inserted into the lumen of the shaft 2 through an opening (not shown) provided on the proximal side of the inner tube 3 of the shaft 2. This opening can also function as an injection port for a drug or the like or a suction port for a fluid or the like in the body.

The shaft 2 preferably has flexibility. As a result, the shaft 2 can be deformed along the shape of the body cavity. Further, in order to maintain the shape, it is preferable that the shaft 2 has elasticity. The shaft 2 is preferably made of resin, metal, or a combination of resin and metal. For example, the shaft 2 includes a resin tube; a metal tube; a hollow body formed by arranging wire rods in a predetermined pattern; at least one of the inner surface and the outer surface of the hollow body coated with resin; or these. For example, a combination of these, for example, a combination of these in the longitudinal direction. The resin tube can be manufactured, for example, by extrusion molding. As the hollow body in which the wire rods are arranged in a predetermined pattern, a tubular body having a mesh structure by simply intersecting or knitting the wire rods, or a coil in which the wire rods are wound is shown. The wire may be one or more single wires, or may be one or more stranded wires. The type of network structure is not particularly limited, and the number of coil turns and the density are not particularly limited. The network structure and the coil may be formed at a constant density throughout the longitudinal direction of the shaft 2, or may be formed at a different density depending on the position of the shaft 2 in the longitudinal direction. In order to increase the flexibility of the metal tube, a notch or a groove may be formed on the outer surface of the metal tube. The shape of the notch or groove can be linear, arcuate, annular, spiral, or a combination thereof.

By using a resin as a constituent material of the shaft 2, it becomes easy to impart flexibility and elasticity to the shaft 2. Further, by using a metal as a constituent material of the shaft 2, the deliverability of the balloon catheter 1 can be improved. Examples of the resin constituting the shaft 2 include polyamide-based resin, polyester-based resin, polyurethane-based resin, polyolefin-based resin, fluorine-based resin, vinyl chloride-based resin, silicone-based resin, natural rubber, and synthetic rubber. Only one of these may be used, or two or more thereof may be used in combination. As the resin constituting the shaft 2, either a thermoplastic resin or a thermosetting resin may be used, but it is particularly preferable to use a thermoplastic resin. Examples of the metal constituting the shaft 2 include stainless steel such as SUS304 and SUS316, platinum, nickel, cobalt, chromium, titanium, tungsten, gold, Ni—Ti alloy, Co—Cr alloy, or a combination thereof. .. The shaft 2 may have a laminated structure made of different materials or the same material.

The balloon 10 has a distal fixing portion 11 fixed to the distal portion of the shaft 2, a proximal fixing portion 12 fixed to the shaft 2 at a position proximal to the distal fixing portion 11, and a distal portion. It has a non-fixed portion 13 that is located between the fixed portion 11 and the proximal fixed portion 12 and is not fixed to the shaft 2. By fixing the balloon 10 to the shaft 2 in this way, the non-fixed portion 13 can be expanded by supplying a fluid to the inside of the balloon 10. Further, when the fluid is discharged from the inside of the balloon 10, the non-fixed portion 13 can be contracted. In FIG. 1, the distal fixing portion 11 of the balloon 10 is fixed to the distal end of the inner tube 3 of the shaft 2. Further, the proximal fixing portion 12 of the balloon 10 is fixed to the distal end portion of the outer tube 4 of the shaft 2. The distal fixing portion 11 and the proximal fixing portion 12 of the balloon 10 can be fixed to the shaft 2 by a method such as welding or adhesion with an adhesive.

As another aspect (not shown), the shaft 2 has a multi-lumen structure having a plurality of lumens, and a first lumen extending in the longitudinal direction of the shaft 2 and a balloon which is a side wall of the shaft 2 and is a balloon. It may have a first side hole formed at an internal position of 10 and communicating with the first lumen. In that case, a fluid feeder can be connected to the proximal side of the first lumen.

The balloon 10 can be manufactured by molding a resin. For example, the balloon 10 can be manufactured by arranging a resin tube extruded by extrusion molding in a mold and biaxially stretching blow molding. The balloon 10 can be formed into any shape depending on the shape of the mold. In addition to biaxial stretch blow molding, the balloon 10 can be manufactured by molding methods such as dip molding, injection molding, and compression molding.

Examples of the resin constituting the balloon 10 include polyamide-based resin, polyester-based resin, polyurethane-based resin, polyolefin-based resin, vinyl chloride-based resin, silicone-based resin, natural rubber, and synthetic rubber. Only one of these may be used, or two or more thereof may be used in combination. Of these, polyamide-based resins, polyester-based resins, and polyurethane-based resins are preferably used. An elastomer resin can be used from the viewpoint of thinning and flexibility of the balloon 10.

The film thickness of the balloon 10 before expansion can be, for example, 10 μm or more, 30 μm or more, or 50 μm or more, and 150 μm or less, 120 μm or less, or 100 μm or less is also allowed.

Examples of the type of fluid supplied to the inside of the balloon 10 include a liquid such as a physiological saline solution, a contrast medium, or a mixed solution thereof, and a gas such as air, nitrogen, and carbon dioxide gas.

The fluid temperature inside the balloon 10 can be, for example, 50 ° C or higher, 52 ° C or higher, or 55 ° C or higher, or 70 ° C or lower, 68 ° C or lower, or 65 ° C or lower. .. As a result, the outer surface of the balloon 10 becomes a temperature suitable for cauterization.

The shape of the non-fixed portion 13 of the balloon 10 is not particularly limited, but may be a sphere, an oval sphere, a prism, a cone, a frustum, or a combination thereof.

As shown in FIG. 1, the balloon catheter 1 has a first electrode portion 21, a long flexible base material 30, and a second electrode portion 22. The first electrode portion 21 is provided on the shaft 2 inside the balloon 10. The flexible base material 30 is provided inside the balloon 10 and outside the first electrode portion 21. The second electrode portion 22 is provided on the flexible base material 30 and can move inside the balloon 10 in a predetermined trajectory, and a high-frequency current is energized between the second electrode portion 22 and the first electrode portion 21. According to such a balloon catheter 1, the position of the second electrode portion 22 provided on the flexible base material 30 is positioned as a balloon as the operator deforms the flexible base material 30 such as bending and twisting. It can be moved inside the 10. Therefore, the portion of the internal fluid of the balloon 10 that is separated from the shaft 2 can be heated. As a result, the surface of the balloon 10 and its vicinity can be easily warmed, and the biological tissue can be efficiently cauterized. Further, since a high frequency current is applied between the first electrode portion 21 and the second electrode portion 22 provided inside the balloon 10, cauterization is possible without disposing a counter electrode plate on the body surface of the patient. Therefore, the risk of electric shock and burns can be reduced.

The first electrode portion 21 and the second electrode portion 22 function as electrodes for heating by high-frequency energization. For example, the first electrode portion 21 and the second electrode portion 22 are connected to the high frequency generator 6 via a conducting wire. As a result, the first electrode portion 21 or the second electrode portion 22 and the high frequency generator 6 are in a state in which electrical conductivity is ensured. As a result, the fluid can be dielectrically heated by applying a high frequency electric field to the fluid arranged between the first electrode portion 21 and the second electrode portion 22. By energizing the high-frequency current between the first electrode portion 21 and the second electrode portion 22 in this way, the balloon catheter 1 functions as an ablation catheter. This ablation catheter can cauterize the target biological tissue with a balloon catheter containing a heated fluid.

The conducting wire connected to the first electrode portion 21 may be a conductive linear body or a layer of a conductive substance formed on the sheet. Such conductors and seats can be arranged inside and outside the shaft 2. The conducting wire connected to the second electrode portion 22 can be arranged, for example, on the flexible base material 30 described later. The conducting wire arranged on the flexible base material 30 can be formed in the same manner as the second electrode portion 22 described later. A part of the members constituting the conducting wire may form the second electrode portion 22.

The high frequency generator 6 may include, for example, a power supply circuit and a high frequency oscillation circuit. Although not shown, an impedance matching circuit may be provided between the first electrode portion 21 and the second electrode portion 22 and the high frequency generator 6.

As shown in FIG. 1, the balloon catheter 1 may be provided with a control device 7 that controls an energized state between the first electrode portion 21 and the second electrode portion 22. It is preferable that the first electrode portion 21 and the second electrode portion 22 are electrically connected to the control device 7 via a conducting wire. The control device 7 may have a current control unit 7a that controls the current value flowing through the first electrode unit 21 and the second electrode unit 22. As a result, the energized state can be controlled according to the state of the biological tissue to be cauterized, and the cauterization can be performed efficiently.

The material constituting the first electrode portion 21 and the second electrode portion 22 may be conductive as long as it has conductivity, and can be composed of a metal or a mixture containing a resin and a metal. Above all, it is preferable to use a conductive resin or a metal such as gold, silver, copper, platinum, platinum iridium alloy, stainless steel, or tungsten.

The first electrode portion 21 may be provided on the shaft 2 inside the balloon 10. The first electrode portion 21 can be provided, for example, on the outside of the inner tube 3 of the shaft 2. Further, it is preferable that the first electrode portion 21 is provided on the shaft 2 at the position of the non-fixed portion 13 of the balloon 10.

The balloon catheter 1 may be provided with only one first electrode portion 21, or may be provided with a plurality of first electrode portions 21. The plurality of first electrode portions 21 may be arranged at different positions in the longitudinal direction of the shaft 2.

Examples of the shape of the first electrode portion 21 include a ring shape, a C-shaped cross section having a notch in the ring, and a coil shape formed by spirally winding a wire rod. FIG. 1 shows an example in which the first electrode portion 21 has a ring shape. When a plurality of first electrode portions 21 are provided as described later, the shapes of the plurality of first electrode portions 21 may be the same or different from each other.

When the plurality of first electrode portions 21 are arranged at different positions in the longitudinal direction of the shaft 2, the value of the high frequency current between the first first electrode portion 21 and the second electrode portion 22 is different. It is preferable that it is larger than the value of the high frequency current between the first electrode portion 21 and the second electrode portion 22 of the above. By making the current value different depending on the electrode portion that is energized in this way, it becomes easy to make the temperature of the internal fluid of the balloon 10 uniform.

The balloon catheter 1 may be provided with only one second electrode portion 22, or may be provided with a plurality of second electrode portions 22. The plurality of second electrode portions 22 may be arranged at positions corresponding to different positions in the longitudinal direction of the shaft 2. Further, the plurality of second electrode portions 22 may be arranged at positions corresponding to different positions in the circumferential direction of the shaft 2. Further, the plurality of second electrode portions 22 may be arranged at positions corresponding to different positions in the longitudinal direction and the circumferential direction of the shaft 2. By arranging the second electrode portions 22 in a dispersed manner in this way, it becomes easy to uniformly heat the entire inside of the balloon 10. The different positions in the circumferential direction of the shaft 2 refer to different positions in the circumferential direction about the longitudinal axis direction of the shaft 2, and the same applies to the following description.

The second electrode portion 22 may be provided on the flexible base material 30. For example, as shown in FIG. 1, the second electrode portion 22 may be arranged on the flexible base material 30, and although not shown, a part of the flexible base material 30 is a second. The electrode portion 22 of the above may be configured.

The flexible base material 30 is a base material that holds at least one of the second electrode portion 22 and the temperature detection portion inside the balloon 10. The flexible base material 30 preferably has elasticity. As a result, the flexible base material 30 can be deformed by applying an external force to the flexible base material 30, and the flexible base material 30 can easily return to its original shape by releasing the external force. Become.

The flexible base material 30 is preferably made of a resin. Examples of the resin constituting the flexible base material 30 include a polyimide resin, a polyamide resin, a polyolefin resin, a polyester resin, a polycarbonate resin, and an epoxy resin.

Examples of the flexible base material 30 include a resin film and a resin sheet having a first surface and a second surface opposite to the first surface. Further, the flexible base material 30 may be a resin linear body, a coil body, or a tube body. The flexible base material 30 may be composed of a single layer or a plurality of layers.

The flexible base material 30 may be made of metal. The flexible base material 30 is preferably in the form of a metal sheet, a linear body, a coil body, or a tube body. The flexible base material 30 may be in the form of a metal sheet or a linear body coated with another material. For example, the conducting wire may be covered with a non-conductive material, a non-existing region in which the coating does not exist may be provided in a part of the coated conducting wire, and the non-existing region may be used as the second electrode portion 22. The shape of the flexible base material 30 can be appropriately selected from a linear shape, a sheet shape, a ribbon shape, a tubular shape, and the like.

When the flexible base material 30 is in the form of a film or a sheet, the thickness of the flexible base material 30 (that is, the film thickness or the sheet thickness) is 0.005 mm or more, 0.01 mm or more, or 0.02 mm. The above is preferable. As a result, the strength can be ensured even if the flexible base material 30 is deformed. The thickness of the flexible base material 30 is preferably 0.05 mm or less, 0.04 mm or less, or 0.03 mm or less. By limiting the thickness to such a thickness, the profile of the balloon 10 at the time of contraction can be reduced.

When the flexible base material 30 is in the form of a film or a sheet, the flexible base material 30 may be thicker or thinner than the second electrode portion 22. Further, the flexible base material 30 may be thicker or thinner than the film thickness of the balloon 10 before expansion.

The flexible base material 30 is long. Examples of the long flexible base material 30 include those formed in a strip shape having a first surface 31 and a second surface 32. The second surface 32 is preferably formed on the side opposite to the first surface 31. The strip-shaped flexible base material 30 has a longitudinal direction, a thickness direction (direction from the first surface 31 to the second surface 32), and a width direction perpendicular to both the longitudinal direction and the thickness direction. There is.

It is preferable that at least a part of the long flexible base material 30 in the longitudinal direction is arranged along the longitudinal direction of the shaft 2. This makes it easier to place the flexible base material 30 in the limited space inside the balloon 10 even when the balloon 10 is contracted. In another embodiment, the flexible substrate 30 may be arranged so as to spirally wind around the shaft 2. In this case, the flexible base material 30 can be deformed by performing an operation such as sliding the flexible base material 30 with respect to the shaft 2.

In FIG. 1, the flexible base material 30 is formed in a strip shape. The width of the strip-shaped flexible base material 30 can be, for example, 1 mm or more, 3 mm or more, or 5 mm or more, or 10 mm or less, or 8 mm or less. When the flexible base material 30 is tubular and arranged around the outer side of the shaft 2, it is preferable that the flexible base material 30 is slidable. When the flexible base material 30 is linear, it is preferable that the flexible base material 30 has elasticity so that it can move in a constant trajectory.

As the second electrode portion 22 provided on the flexible base material 30, for example, a metal oxide or a thin film of metal can be used. Examples of the method of providing the thin film on the flexible base material 30 include an etching method, a vacuum vapor deposition method, a sputtering method, an ion plating method, a plating method, and a coating method.

The thickness of the thin-film second electrode portion 22 may be, for example, 100 nm or more, 500 nm or more, or 1000 nm or more, and it is also acceptable that the thickness is 100 μm or less, 50 μm or less, or 30 μm or less.

A flexible printed circuit board (FPC) can be used as the flexible base material 30 provided with at least one of the second electrode unit 22, the temperature detection unit 50, and the outer temperature detection unit 55. ..

The shape of the second electrode portion 22 may be, for example, a ring shape, a C-shaped cross section with a notch in the ring, or a coil formed by spirally winding a wire rod. The second electrode portion 22 having such a shape can be preferably used when the flexible base material 30 is a resin linear body, coil body, or tube body. For example, the ring-shaped second electrode portion 22 can be fixed to the flexible base material 30 by caulking, adhering with an adhesive, welding, or the like.

The proximal side of the flexible base material 30 can be connected to a member arranged on the hand side. For example, it is preferable that the balloon catheter 1 is provided with a pusher 40 that is fixed to the flexible base material 30 and can slide with respect to the shaft 2. When the operator grips and slides the pusher 40, the flexible base material 30 is deformed, so that the second electrode portion 22 can be moved. FIG. 1 shows an example in which the pusher 40 is fixed to the proximal end of the first flexible base material 30a.

Although not shown, the proximal side of the flexible substrate 30 may be fixed to the shaft 2 (preferably the outer tube 4) instead of the pusher 40. As a result, the operator can slide the outer tube 4 with respect to the inner tube 3 of the shaft 2 to deform the flexible base material 30, so that the second electrode portion 22 can be moved.

The distal side of the flexible substrate 30 can be fixed to the shaft 2. As a result, the position on the distal side of the flexible base material 30 is fixed, so that the position on the proximal side of the flexible base material 30 is moved to move the second electrode portion 22 in a predetermined trajectory. be able to. The distal side of the flexible base material 30 may be fixed to the distal fixing portion 11 of the balloon 10 of the shaft 2, or may be fixed to the non-fixing portion 13 of the balloon 10 of the shaft 2. The shape may be such that the distal end of the flexible base material 30 is not fixed to the shaft 2 or the balloon 10.

Although not shown, for example, a protrusion may be provided on the distal side of the shaft 2 inside the balloon 10. In detail, it is preferable that the outer surface of the shaft 2 is provided with a protrusion. As a result, the flexible base material 30 can be pushed and pulled so that the flexible base material 30 can move in the longitudinal direction inside the balloon 10. Since the protrusions act as stoppers, the distal end of the flexible base material 30 comes into contact with the protrusions on the shaft 10 so that the flexible base material 30 does not move any further in the longitudinal direction. After that, by further pushing the flexible base material 30 toward the distal side, the flexible base material 30 bends, and the flexible base material 30 moves inside the balloon 10 from the vicinity of the shaft 2 to the vicinity of the outside of the balloon 10. Such a predetermined trajectory can be imparted to the possibility base material 30.

The flexible base material 30 does not have to be fixed to the non-fixed portion 13 of the balloon 10. As a result, it is possible to prevent the second electrode portion 22 provided on the flexible base material 30 from coming into contact with the balloon 10.

The locus drawn by the second electrode portion 22 will be described with reference to FIGS. 1 and 2. In FIG. 1, the strip-shaped first flexible substrate 30a has an intermediate portion located between the distal end, the proximal end, the distal end and the proximal end. The distal end of the first flexible substrate 30a is fixed to the inner tube 3 of the shaft 2. The proximal end of the first flexible substrate 30a is fixed to the pusher 40. The intermediate portion of the first flexible base material 30a is not fixed to the shaft 2 and the pusher 40. As shown in FIG. 1, the pusher 40 is moved relative to the inner tube 3 of the shaft 2 to the distal side, and the proximal end of the first flexible base material 30a is moved to the distal side. Then, the portion of the intermediate portion arranged inside the balloon 10 is curved. At this time, the second electrode portion 22 draws a locus that moves from the inside to the outside toward the distal side. From the state of FIG. 1, the pusher 40 is moved relative to the inner tube 3 of the shaft 2 to the proximal side, and the proximal end portion of the first flexible base material 30a is moved to the proximal side. Then, as shown in FIG. 2, the curvature of the intermediate portion is gradually extended and approaches a straight line. At this time, the second electrode portion 22 draws a locus that moves from the outside to the inside toward the proximal side. The flexible base material 30 is a factor that controls the trajectory of the second electrode portion 22. It is desirable that the trajectory of the second electrode portion 22 be constant during use of the catheter. Therefore, the material and shape of the flexible base material 30 can be selected.

The predetermined locus of the second electrode portion 22 preferably includes a locus that moves in the radial direction inside the balloon 10. As a result, not only the portion inside the balloon 10 near the shaft 2 but also the portion near the outside inside the balloon 10 away from the shaft 2 can be efficiently heated. The predetermined locus of the second electrode portion 22 may include a locus of movement from the proximal side to the distal side of the balloon 10 or from the distal side to the proximal side.

In FIG. 1, the flexible base material 30 is formed in a strip shape having a first surface 31 and a second surface 32. The first surface 31 faces the shaft 2 side, and the second surface 32 faces the balloon 10 side. In that case, it is preferable that the second electrode portion 22 is arranged on at least one of the first surface 31 side and the second surface 32 side. The deformation operation of the flexible base material 30 facilitates the movement of the second electrode portion 22 in the radial direction of the balloon 10. Further, when the flexible base material 30 is stretched, the flexible base material 30 is easily arranged along the longitudinal direction of the shaft 2, and the profile of the balloon 10 at the time of contraction can be reduced.

As shown in FIG. 1, it is preferable that the second electrode portion 22 is arranged on the second surface 32 side of the flexible base material 30 and not on the first surface 31 side. As a result, even when the degree of curvature of the flexible base material 30 is small, the second electrode portion 22 is likely to be located outside the balloon 10 in the radial direction, so that the surface of the balloon 10 or its vicinity can be moved. It becomes easier to warm.

FIG. 3 shows a side sectional view showing a modified example of the balloon catheter 1 shown in FIG. As shown in FIG. 3, it is preferable that the second electrode portion 22 is arranged on the first surface 31 side of the flexible base material 30 and not on the second surface 32 side. As a result, the second electrode portion 22 is arranged inward of the flexible base material 30 even when the flexible base material 30 is maximally curved. Therefore, the risk that the second electrode portion 22 comes into contact with the inner surface of the balloon 10 can be reduced.

Although not shown, the second electrode portion 22 may be arranged on both the first surface 31 side and the second surface 32 side of the flexible base material 30. By arranging the second electrode portion 22 on the first surface 31 and the second surface 32 of the flexible base material 30 in this way, the internal fluid of the balloon 10 can be rapidly heated. In this embodiment, the second electrode portion 22 arranged on the first surface 31 side of the flexible base material 30 and the second electrode portion 22 arranged on the second surface 32 side are flexible. It is preferable that the base material 30 is at a different position in the longitudinal direction. Further, the second electrode portion 22 arranged on the first surface 31 side of the flexible base material 30 and the second electrode portion 22 arranged on the second surface 32 side are made of a flexible base material. It is more preferable that the electrodes do not overlap each other in the longitudinal direction of 30. By arranging the plurality of second electrode portions 22 in a staggered manner in this way, the risk of the internal fluid being locally overheated can be reduced.

The flexible base material 30 may be configured to be rotatable about the longitudinal axis direction of the shaft 2. By rotating the flexible base material 30, the second electrode portion 22 can be moved in the circumferential direction. By rotating the flexible base material 30, the internal fluid of the balloon 10 can be uniformly heated over the entire circumferential direction.

FIG. 1 shows a state in which the flexible base material 30 is most curved (for example, a state in which the pusher 40 is moved to the most distal side). The flexible base material 30 is curved inside the balloon 10, and as shown in FIG. 1, the second electrode portion 22 is a position including the outer end of the flexible base material 30 at the time of maximum bending. It is preferably formed in. When the flexible base material 30 is most curved, the second electrode portion 22 is likely to be located outside the balloon 10 in the radial direction, so that the surface of the balloon 10 and its vicinity are easily warmed.

As shown in FIG. 1, the first electrode portion 21 and the second electrode portion 22 may be arranged so as to overlap each other in the longitudinal direction of the shaft 2 when the flexible base material 30 is maximally curved. .. As a result, the first electrode portion 21 and the second electrode portion 22 can be brought close to each other at the time of bending, so that the vicinity of these electrode portions can be easily heated.

Although not shown, the first electrode portion 21 may be located distal to the second electrode portion 22 when the flexible base material 30 is maximally curved. Further, it is more preferable that the first electrode portion 21 and the second electrode portion 22 are arranged so as not to overlap each other in the longitudinal direction of the shaft 2 at the time of the maximum bending. As a result, the first electrode portion 21 and the second electrode portion 22 can be separated from each other, so that a wide range of the internal fluid of the balloon 10 can be easily heated.

A plurality of flexible base materials 30 may be provided inside the balloon 10. In addition, in order to reduce the profile of the balloon 10 at the time of contraction, it is preferable that the plurality of flexible base materials 30 are arranged at different positions in the circumferential direction of the shaft 2.

FIG. 4 shows a side sectional view showing a modified example of the balloon catheter 1 shown in FIG. 1, and FIG. 5 shows a VV sectional view of the balloon catheter 1 shown in FIG. The balloon catheter 1 shown in FIGS. 4 to 5 is provided with a plurality of flexible base materials 30. The plurality of flexible base materials 30 are arranged at different positions in the circumferential direction of the shaft 2. The second electrode portion 22 is arranged on each of the plurality of flexible base materials 30. By differentiating the positions of the plurality of flexible base materials 30 in the circumferential direction, the profile of the balloon 10 at the time of contraction can be reduced. Further, by arranging the plurality of second electrode portions 22 on different flexible base materials 30, the internal fluid can be heated over the entire circumferential direction of the shaft 2. As a result, the occurrence of cauterization unevenness in the circumferential direction can be suppressed.

The number of flexible base materials 30 provided with the second electrode portion 22 for heating can be 2 or more, 4 or more, or 6 or more. This makes it possible to efficiently heat the internal fluid. The number of flexible substrates 30 is preferably 24 or less, 20 or less, or 16 or less. As a result, the profile of the balloon 10 at the time of contraction can be reduced.

In FIG. 5, four flexible base materials arranged side by side in the circumferential direction are provided inside the balloon 10. In the following, these four flexible base materials are referred to as a first flexible base material 30a, a second flexible base material 30b, a third flexible base material 30c, and a fourth flexible base material. It is referred to as a material 30d.

In FIGS. 4 to 5, the first flexible base material 30a, the second flexible base material 30b, the third flexible base material 30c, and the fourth flexible base material 30d have a second One electrode portion 22 is provided for each. By arranging the first second electrode portion 22 with respect to the one flexible base material 30 in this way, it becomes easier to adjust the temperature distribution of the internal fluid of the balloon 10. In FIG. 4, the five first electrode portions 21 are arranged side by side in the longitudinal direction of the shaft 2. In FIG. 4, all five first electrode portions 21 have a ring shape.

As shown in FIG. 4, it is preferable that the plurality of flexible base materials 30 are not fixed to each other in at least a part of the non-fixed portion 13 of the balloon 10. As a result, since the plurality of flexible base materials 30 can be moved individually, the second electrode portion 22 provided on each flexible base material 30 can also be moved individually.

FIG. 6 shows a cross-sectional view showing still another modification of the balloon catheter 1 shown in FIG. As shown in FIG. 6, a plurality of second electrode portions 22 may be provided on one flexible base material 30 (for example, the first flexible base material 30a). With such a configuration, the temperature distribution of the internal fluid of the balloon 10 can be finely adjusted.

When a plurality of second electrode portions 22 are provided on one flexible base material 30, it is preferable that the plurality of second electrode portions 22 are arranged at different positions in the longitudinal direction of the shaft 2. .. This facilitates fine adjustment of the temperature distribution of the internal fluid of the balloon 10 in the longitudinal direction of the shaft 2.

In FIG. 5, the balloon catheter 1 has at least a first flexible base material 30a and a second flexible base material 30b arranged at different positions in the circumferential direction. Each flexible base material 30 has a first surface 31 and a second surface 32, respectively, and the first surface 31 of each flexible base material 30 faces the shaft 2 side, and each flexible base material 30 The second surface 32 of the balloon 10 faces the balloon 10. In this case, it is preferable that the second electrode portions 22 are provided on the second surface 32 side of the first flexible base material 30a and the second surface 32 side of the second flexible base material 30b, respectively. .. As a result, the second electrode portion 22 is likely to be located outside the balloon 10 in the radial direction, so that the surface of the balloon 10 and its vicinity can be easily warmed. The temperature distribution of the internal fluid of the balloon 10 can be easily adjusted. As shown in FIG. 5, the first surfaces 31 of all the flexible base materials 30 arranged inside the balloon 10 are arranged so as to face the shaft 2 side, and are arranged on each second surface 32 side. The second electrode portion 22 may be arranged respectively.

Although not shown, second electrode portions 22 are provided on the first surface 31 side of the first flexible base material 30a and on the first surface 31 side of the second flexible base material 30b, respectively. May be good. Thereby, the risk that the second electrode portion 22 comes into contact with the inner surface of the balloon 10 can be reduced.

Although not shown, second electrode portions 22 are provided on the second surface 32 side of the first flexible base material 30a and on the first surface 31 side of the second flexible base material 30b, respectively. May be good. This makes it easier to adjust the temperature distribution of the internal fluid of the balloon 10.

Although not shown, the balloon catheter 1 is arranged at different positions in the circumferential direction of the first flexible base material 30a, the second flexible base material 30b, and the third flexible base material 30c. And a fourth flexible base material 30d, each flexible base material 30 has a first surface 31 and a second surface 32, respectively, and a first of the flexible base materials 30. When the first surface 31 faces the shaft 2 side and the second surface 32 of each flexible base material 30 faces the balloon 10 side, the first surface 31 side and the second surface 31 side of the first flexible base material 30a. The second surface 32 side of the flexible base material 30b, the first surface 31 side of the third flexible base material 30c, and the second surface 32 side of the fourth flexible base material 30d, respectively. It is preferable that the electrode portion 22 is provided. In this case, the first flexible base material 30a, the second flexible base material 30b, the third flexible base material 30c, and the fourth flexible base material 30d are arranged next to each other in the circumferential direction. It is preferable that it is. By alternately arranging the second electrode portion 22 arranged on the first surface 31 side and the second electrode portion 22 arranged on the second surface 32 side in the circumferential direction in this way, the internal fluid is localized. It reduces the risk of overheating and makes it easier to uniformly heat the internal fluid of the balloon 10.

Although not shown, the balloon catheter 1 has at least a first flexible base material 30a and a second flexible base material 30b arranged at different positions in the circumferential direction, and the first flexible base material 30a is provided. When the second electrode portion 22 is provided on the flexible base material 30a and the second flexible base material 30b, respectively, the first flexible base material 30a and the second flexible base material 30b are provided. Is curved inside the balloon 10 and is provided on the first flexible base material 30a at the time of maximum bending of both the first flexible base material 30a and the second flexible base material 30b. The second electrode portion 22 may be located distal to the second electrode portion 22 provided on the second flexible base material 30b. In this way, by configuring the flexible base material 30 so that the positions of the plurality of second electrode portions 22 are displaced when the flexible base material 30 is curved, the risk of the internal fluid being locally overheated is reduced, and the balloon 10 is far away. It becomes easier to heat the fluid in a wide range from the position side to the proximal side.

1 to 3 show an example in which one flexible base material 30 can be deformed by operating one pusher 40. 4 and 6 show an example in which a plurality of flexible base materials 30 can be deformed at the same time by operating one pusher 40. As another example, as shown in FIG. 7, the pusher 41 is fixed to the first push portion 43a fixed to the first flexible base material 30a and the second flexible base material 30b. It may have a second push portion 43b and the like. Further, the pusher 41 may have a third pusher 43c fixed to a third flexible substrate (not shown). That is, one push portion may be fixed to one flexible base material 30. By moving each push portion individually, each flexible base material 30 can be individually deformed. As a result, each of the second electrode portions 22 can also be moved individually.

The pusher 41 may have a pusher body 42 and a plurality of pushers 43 that move relative to the pusher body 42. Examples of the plurality of push portions include a configuration having a first push portion 43a and a second push portion 43b. Examples of the pushing portion 43 include a slider that can move in the longitudinal direction of the shaft 2.

Another embodiment in which the flexible base material 30 is provided with the second electrode portion 22 will be described. Although not shown, in a mode in which a part of the flexible base material 30 constitutes the second electrode portion 22, the flexible base material 30 is inside the balloon 10 and outside the shaft 2. There is an example in which the conductive linear body is arranged in the above, and a part of the conductive linear body is the second electrode portion 22. In another embodiment, the flexible base material 30 may be an elastic coated conductor that is arranged inside the balloon 10 and outside the shaft 2. A non-existent region where no coating is present is provided in a part of the coated conductor. In that case, the non-existing region may be used as the second electrode portion 22. When the flexible base material 30 is a coated conductor, the portion of the coated conductor that has a coating is linear, and the portion of the second electrode portion 22 that is not coated is coiled. You can also do it.

Another embodiment in which the second electrode portion 22 is provided as a separate member on the flexible base material 30 will be described. Although not shown, the second electrode portion 22 is a ring-shaped metal fixed to a tubular flexible base material 30 which is inside the balloon 10 and is arranged outside the shaft 2. May be good. The second electrode portion 22 is formed by passing a metal ring through a resin or metal tube and fixing the flexible base material 30 by caulking, adhering with an adhesive, welding, or the like. It is preferable that the tubular flexible base material 30 has a second electrode portion 22 formed at the distal end and the proximal side is connected to the pusher 40. By moving the flexible base material 30 toward the distal side or the proximal side along the longitudinal direction of the shaft 2, the second electrode portion 22 moves inside the balloon 10 in a predetermined trajectory. The metal tube is preferably a flexible coil in which a metal wire is spirally wound.

It is preferable that the temperature detection unit is provided at least one of the inside and the outside of the balloon 10. This makes it possible to detect the temperature of the internal fluid of the balloon 10 and estimate the temperature of the tissue to be cauterized.

As the temperature detection unit, a temperature sensor such as a thermocouple or a temperature measuring element can be used. One or more temperature detectors may be provided for one flexible substrate.

In FIGS. 4 and 6 to 7, the temperature detection unit 50 is provided on the flexible base material 30. That is, the temperature detecting unit 50 is provided inside the balloon 10. Thereby, the fluid temperature inside the balloon 10 can be detected. As a matter of course, the balloon catheter 1 shown in FIGS. 1 to 3 may be provided with the temperature detection unit 50.

In FIGS. 4 and 6, the temperature detection unit 50 is provided on the second surface 32 side of the flexible base material 30. That is, the temperature detection unit 50 and the second electrode unit 22 are provided on the same surface side. On the other hand, in FIG. 7, the temperature detection unit 50 and the second electrode unit 22 are provided on different surface sides. The temperature detection unit 50 may be provided on the first surface 31 side of the flexible base material 30. In order to improve the accuracy of estimating the temperature of the structure to be ablated, it is preferable that the flexible base material 30 is provided on the second surface 32 side.

In FIG. 4, the balloon catheter 1 has a current control unit 7a that controls a current value flowing through the second electrode unit 22. In that case, it is preferable that the current control unit 7a controls the current value flowing through the second electrode unit 22 arranged closest to the temperature detection unit 50 according to the temperature detected by the temperature detection unit 50. .. In this way, the internal fluid can be efficiently warmed by feeding back the detection result of the temperature detection unit 50 to the current control unit 7a and controlling the current value flowing through the second electrode unit 22. Here, the fact that the temperature detection unit 50 is arranged closest to the temperature detection unit 50 means that the flexible base material 30 provided with the second electrode unit 22 is arranged closest to the temperature detection unit 50 at the time of maximum curvature. Point to.

Although not shown, it is preferable that all the flexible base materials provided inside the balloon 10 are provided with temperature detection units. Thereby, the temperature inside the balloon 10 can be detected in more detail.

Although not shown, the shaft 2 may be provided with an inner temperature detection unit. Thereby, the temperature of the internal fluid in the vicinity of the shaft 2 can be detected. The inner temperature detection unit may be attached to the outer surface of the shaft 2, may be embedded in the peripheral wall of the shaft 2, or may be embedded in the first electrode portion 21. Only one inner temperature detection unit may be provided for the shaft 2, or a plurality of inner temperature detection units may be provided.

As shown in FIGS. 4 and 6 to 7, it is preferable that the outside temperature detecting unit 55 is provided on the outside of the balloon 10. This makes it easier to estimate the temperature of the living tissue to be cauterized, and cauterization can be performed efficiently. As a matter of course, the balloon catheter 1 shown in FIGS. 1 to 3 may be provided with the outer temperature detecting unit 55.

As a method of arranging the outer temperature detecting unit 55 on the outer side of the balloon 10, the outer flexible base material 36 is fixed to the outer surface of the balloon 10 as shown in FIGS. 4 and 6 to 7, and the outer flexible base material 36 is fixed. An embodiment in which the outside temperature detection unit 55 is arranged on the material 36 can be mentioned. By providing the outer temperature detection unit 55 on the deformable outer flexible base material 36 in this way, it is possible to withstand the contraction and expansion of the balloon 10.

The outer flexible base material 36 can have the same configuration as the flexible base material 30 arranged inside the balloon 10. For example, in FIG. 4, the outer flexible base material 36 is formed in a band shape having a first surface 37 and a second surface 38. The outer flexible base material 36 is fixed to the outer surface of the balloon 10 so that the first surface 37 faces the inside of the balloon 10 and the second surface 38 faces the outside. The outer temperature detection unit 55 is arranged on the second surface 38 side of the outer flexible base material 36.

Although not shown, the outer temperature detection unit 55 may be arranged on the first surface 37 side of the outer flexible base material 36. In that case, the outer temperature detection unit 55 may be arranged between the outer flexible base material 36 and the balloon 10. The balloon 10 and the outer flexible base material 36 can be fixed by, for example, welding or adhesion.

Only one outer temperature detecting unit 55 may be provided for the balloon 10, but it is preferable that a plurality of outer temperature detecting units 55 are provided in order to make it easier to grasp the temperature distribution on the outer surface of the balloon 10. It is preferable that the plurality of outside temperature detecting units 55 are arranged at different positions in the circumferential direction of the shaft 2 or at different positions in the longitudinal direction of the shaft 2.

The balloon catheter 1 further includes a current control unit 7a that controls the value of the current flowing through the second electrode unit 22, and the current control unit 7a is a second unit according to the temperature detected by the outer temperature detection unit 55. It is preferable to control the value of the current flowing through the electrode portion 22. Above all, the current control unit 7a can control the current value flowing through the second electrode unit 22 arranged closest to the outer temperature detection unit 55 according to the temperature detected by the outer temperature detection unit 55. More preferred. By feeding back the detection result of the outside temperature detection unit 55 to the current control unit 7a and controlling the current value flowing through the second electrode unit 22 in this way, the surface of the balloon 10 close to the biological tissue to be cauterized and its surface and its surface. The internal fluid can be efficiently heated in the vicinity. Here, the fact that the second electrode portion 22 is arranged closest to the outer temperature detecting portion 55 means that the flexible base material 30 provided with the second electrode portion 22 is arranged closest to the flexible base material 30 at the time of maximum curvature. Means.

The value of the current flowing through the second electrode portion 22 may be constant or may change with time. When a plurality of second electrode portions 22 are provided inside the balloon 10, the current value flowing through the first second electrode portion 22 is larger than the current value flowing through the other second electrode portions 22. Is preferable. By making the current value different depending on the electrode portion that is energized in this way, it becomes easy to make the temperature of the internal fluid of the balloon 10 uniform.

It is preferable that the potential measurement electrode portion 25 for measuring the internal potential is provided on the outside of the balloon 10. As a result, the potential of the living tissue to be cauterized can be measured. Therefore, by using this measurement result, for example, whether or not the pulmonary vein was isolated after cauterization by pulmonary vein isolation, that is, the cauterization is sufficient. You can check if it was there. Conventionally, it has been confirmed whether or not the pulmonary veins have been isolated by using, for example, an electrode catheter having a loop-shaped tip separately from the balloon catheter for ablation, but the potential measurement electrode portion is outside the balloon 10. By providing 25, such an electrode catheter becomes unnecessary. As a matter of course, the balloon catheter 1 shown in FIGS. 1 to 3 may be provided with the potential measurement electrode portion 25.

The outer flexible base material 36 may be fixed to the outer surface of the balloon 10, and the potential measurement electrode portion 25 may be provided on the outer flexible base material 36. As a method of providing the potential measurement electrode portion 25 on the outer flexible base material 36, the description of the method of providing the second electrode portion 22 on the flexible base material 30 can be referred to. The outer flexible base material 36 may be provided with a potential measurement electrode unit 25 and an outer temperature detection unit 55.

The potential measurement electrode portion 25 is preferably provided at a position including the outer end when the balloon 10 is expanded. Since the position including the outer end of the balloon 10 is likely to come into contact with the living tissue to be ablated, by providing the potential measurement electrode portion 25 at this position, it is confirmed whether or not the pulmonary vein is isolated. It will be easier.

Only one potential measurement electrode unit 25 may be provided for the balloon 10, but it is preferable that a plurality of potential measurement electrode units 25 are provided. Above all, it is more preferable that the plurality of potential measurement electrode portions 25 are provided at different positions in the circumferential direction of the balloon 10. This makes it easier to see if the entire circumferential direction of the pulmonary veins has been isolated.

In order to confirm the position of the balloon 10 in the longitudinal direction of the shaft 2, it is preferable that the shaft 2 is provided with one or more radiation opaque markers (hereinafter, may be simply referred to as markers). The shape of the marker is preferably a cylinder, and examples thereof include a cylinder, a polygonal cylinder, a C-shaped cross section with a notch in the cylinder, and a coil shape in which a wire rod is wound.

The marker is preferably composed of an X-ray opaque material such as lead, barium, iodine, tungsten, gold, platinum, iridium, stainless steel, titanium, and cobalt-chromium alloy.

As shown in FIGS. 4 and 6 to 7, it is preferable that the marker 60 is provided at the position of the proximal end of the non-fixed portion 13 of the balloon 10 on the shaft 2. This makes it possible to confirm the position of the balloon 10 near the pulmonary vein. The marker 60 may be arranged so as to overlap the proximal fixed portion 12 and the non-fixed portion 13 of the balloon 10.

As shown in FIGS. 4 and 6 to 7, it is preferable that the marker 61 is provided at the position of the distal end portion of the non-fixed portion 13 of the balloon 10 on the shaft 2. This makes it possible to confirm the insertion state of the distal end of the balloon 10 into the pulmonary vein. The marker 61 may be arranged so as to overlap the distal fixed portion 11 and the non-fixed portion 13 of the balloon 10. As a matter of course, at least one of the marker 60 and the marker 61 may be provided on the balloon catheter 1 shown in FIGS. 1 to 3.

Although not shown, a marker may be provided at a position at the center of the non-fixed portion 13 of the balloon 10 on the shaft 2. This makes it possible to confirm the insertion state of the balloon 10 in the vicinity of the center of the pulmonary vein.

Although not shown, the balloon catheter 1 may be provided with a vibration generating portion for applying vibration to the internal fluid of the balloon 10. The vibration generating portion is connected so as to communicate with the inside of the balloon 10. Since the internal fluid of the balloon 10 can be agitated by vibration by the vibration generating portion, the temperature of the internal fluid can be made uniform. As the vibration generating unit, for example, an ultrasonic vibration device can be used.

1: Balloon catheter 2: Shaft 3: Inner tube 4: Outer tube 5: Fluid feeder 6: High frequency generator 7: Control device 7a: Current control unit 10: Balloon 11: Distal fixation part 12: Proximal fixation part 13 : Non-fixed portion 21: First electrode portion 22: Second electrode portion 25: Potential measurement electrode portion 30: Flexible base material 30a: First flexible base material 30b: Second flexible base Material 30c: Third flexible base material 30d: Fourth flexible base material 31: First surface 32: Second surface 36: Outer flexible base material 37: First surface 38: Second surface 40 , 41: Pusher 50: Temperature detection unit 55: Outside temperature detection unit 60, 61: Marker

Claims (14)

A shaft with a distal end and a proximal end,
A balloon provided at the distal portion of the shaft and
A first electrode portion inside the balloon and provided on the shaft, and
A long flexible base material provided inside the balloon and outside the first electrode portion, and
A balloon provided on the flexible base material, having a second electrode portion that can move inside the balloon in a predetermined trajectory and is energized with a high-frequency current between the first electrode portion and the balloon. catheter. The balloon catheter according to claim 1, wherein the predetermined locus includes a locus that moves in the radial direction inside the balloon. The flexible base material is formed in a band shape having a first surface and a second surface, and is arranged so that the first surface faces the shaft side and the second surface faces the balloon side.
The balloon catheter according to claim 1 or 2, wherein the second electrode portion is arranged on at least one of the first surface side and the second surface side. The balloon catheter according to claim 3, wherein the second electrode portion is arranged on the first surface side and is not arranged on the second surface side. The balloon catheter according to claim 3, wherein the second electrode portion is arranged on the second surface side and is not arranged on the first surface side. The balloon catheter according to any one of claims 1 to 5, further provided with a pusher fixed to the flexible substrate and slidable with respect to the shaft. The flexible substrate is curved inside the balloon and
The balloon catheter according to any one of claims 1 to 6, wherein the second electrode portion is formed at a position including the outer end at the time of maximum bending of the flexible base material. A plurality of the flexible base materials are provided, and the flexible base material is provided.
The plurality of flexible substrates are arranged at different positions in the circumferential direction of the shaft.
The balloon catheter according to any one of claims 1 to 7, wherein the second electrode portion is arranged on each of the plurality of flexible substrates. The balloon catheter according to any one of claims 1 to 8, wherein a temperature detection unit is further provided on the flexible base material. A plurality of the first electrode portions are provided, and the first electrode portion is provided.
The plurality of first electrode portions are arranged at different positions in the longitudinal direction of the shaft.
The value of the high frequency current between the first electrode portion and the second electrode portion is larger than the value of the high frequency current between the other first electrode portion and the second electrode portion. Item 8. The balloon catheter according to any one of Items 1 to 9. The balloon catheter according to any one of claims 1 to 10, further comprising a potential measurement electrode portion for measuring an internal potential on the outside of the balloon. The balloon catheter according to any one of claims 1 to 11, further comprising an outer temperature detection unit on the outside of the balloon. It further has a control unit that controls the value of the current flowing through the second electrode unit.
The 12th aspect of the present invention, wherein the control unit controls a current value flowing through the second electrode unit, which is arranged closest to the outside temperature detection unit, according to the temperature detected by the outside temperature detection unit. Balloon catheter. The balloon catheter according to any one of claims 1 to 13, further comprising an inner temperature detection unit on the shaft.

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