WO2022190225A1 - Balloon-type electrode catheter - Google Patents

Abstract

The purpose of the present invention is to provide a balloon-type electrode catheter that is capable of uniformly cooling the interior of the balloon in the circumferential direction thereof. An electrode catheter (100) according to the present invention comprises an outer tube (10), an electrical connector (21), a balloon (30), an inner shaft (41, 46), surface electrodes (51 to 54) formed on an outer surface of the balloon, and a conducting wire (70) for the surface electrodes. Fluid supply sub-lumens and fluid discharge sub-lumens are formed in the outer tube, the fluid supply sub-lumens are open at the distal-end surface of the outer tube, the fluid discharge sub-lumens are open at the outer circumferential surface of the outer tube in the vicinity of the proximal end of an expansion section of the balloon, and when the outer tube is divided into two parts by an arbitrary imaginary plane, the area ratio of the fluid supply sub-lumens and the fluid discharge sub-lumens in a lateral cross-sectional view of the divided parts is always in the range of 40:60 to 60:40.

Description

balloon electrode catheter

The present invention relates to a balloon-type electrode catheter for high-frequency ablation treatment.

As a balloon-type electrode catheter (intravascular ablation device) for high-frequency ablation treatment of a vessel or its surrounding tissue, conventionally, an outer tube (catheter shaft), a balloon connected to the tip of the outer tube, and an outer tube are used. The inner tube (guidewire lumen) inserted through the lumen of the balloon and the balloon, the lumen tube (supply lumen) inserted through the lumen of the outer tube to supply fluid to the inside of the balloon, and the inside of the balloon A device comprising a lumen tube (return lumen) inserted through the lumen of the outer tube for discharging the fluid supplied to the balloon and a surface electrode provided on the outer surface of the balloon is introduced (see below). See Patent Document 1).

A balloon that constitutes the balloon-type electrode catheter described in Patent Document 1 has an expansion portion that expands and contracts and neck portions formed at both ends thereof, and the proximal neck portion is fixed to the outer tube. and the distal neck portion is fixed to the inner tube (guidewire lumen).

Further, in the balloon-type electrode catheter described in Patent Document 1, a fluid supplied to the inside of the balloon by a lumen tube (supply lumen) is circulated inside the balloon, and then discharged from the lumen tube (return lumen). Ejection is intended to cool the interior of the balloon, thereby cooling the tissue surrounding the surface electrodes.

However, in the balloon electrode catheter described in Patent Document 1, both the lumen tube (supply lumen) and the lumen tube (return lumen) are open near the proximal end of the balloon. After expansion, the fluid supplied to the inside of the balloon from the opening of the lumen tube (supply lumen) is immediately discharged from the opening of the lumen tube (return lumen) without flowing and circulating in the distal direction. Therefore, there is a problem that the inside of the balloon and the surrounding tissue of the surface electrodes cannot be sufficiently cooled.

In particular, when performing ablation treatment of a tumor or the like with a balloon electrode catheter, it is necessary to apply a high voltage to the surface electrode. When the temperature exceeds 80° C., fibrosis is likely to occur, and if the fibrotic tissue intervenes, subsequent cauterization treatment becomes substantially impossible.

In response to the above problems, the present applicant has proposed a balloon-type electrode catheter for performing high-frequency ablation treatment, an outer tube having a central lumen and a plurality of sub-lumens arranged around the central lumen,
a current-carrying connector arranged on the base end side of the outer tube;
It has an expanding portion that expands and contracts and neck portions that are continuous to both ends thereof, the proximal neck portion being fixed to the distal end portion of the outer tube, and the expanding portion enclosing the distal end portion of the outer tube. a balloon connected to the distal end side of the outer tube;
an inner shaft that is inserted through the central lumen of the outer tube, extends into the balloon from the opening of the central lumen, is fixed to a distal neck portion of the balloon, and extends to the outside of the balloon;
a surface electrode made of a thin metal film formed on the outer surface of the balloon at least in the expanded portion of the balloon;
a conductor for electrically connecting the surface electrode and the conducting connector;
at least one of the sub-lumens of the outer tube is a fluid-supplying sub-lumen through which the fluid is circulated in order to supply the fluid to the inside of the balloon;
at least one of the sub-lumens of the outer tube is a fluid-discharging sub-lumen through which the fluid supplied to the balloon is discharged from the balloon;
The outer tube has a tubular portion extending in the proximal direction from the proximal end of the extension portion or a position in the vicinity thereof;
a semi-circular tubular portion extending from the base end of the expansion portion or a position near it to the inside of the expansion portion in a distal direction beyond an axially intermediate position of the expansion portion;
The fluid-supplying sub-lumen is arranged inside the circular tubular portion and the semi-circular tubular portion, and is open at the distal end surface of the semi-circular tubular portion (therefore, the opening of the fluid-supplying sub-lumen is , located on the tip side of the intermediate position in the axial direction of the extension),
The fluid discharge sub-lumen is arranged inside the circular tubular portion and opens at the distal end surface of the circular tubular portion. proposed a balloon-type electrode catheter (located at or near the proximal end) (see Patent Document 2 below).

According to the balloon electrode catheter having such a configuration, the fluid is discharged (supplied) from the opening of the fluid supply sub-lumen formed in the distal end surface of the semicircular tubular portion, which is the distal end surface of the outer tube. The fluid is discharged from the opening of the fluid discharge sub-lumen formed in the distal end surface of the circular tubular portion located at or near the proximal end, thereby causing the fluid to flow from the distal end side to the proximal end side inside the balloon. Can form a flow. As a result, the inside of the balloon and, by extension, the tissue surrounding the surface electrodes can be sufficiently cooled.

Japanese Patent Publication No. 2013-532564 WO2020/035919

However, the balloon-type electrode catheter described in Patent Document 2 cannot exhibit a uniform cooling effect in the circumferential direction of the balloon.
That is, the flow (flow rate) of the fluid from the distal end side to the proximal end side inside the balloon is small on the semicircular side where the semicircular tubular portion is arranged (where the fluid supply sub-lumen extends). It is larger on the semi-peripheral side where the tubular portion is not arranged (where the opening of the fluid discharge sub-lumen is located).
For this reason, the inside of the balloon on the semicircular side where the semicircular tubular portion is arranged cannot be sufficiently cooled, and there is a new problem that cooling unevenness (in other words, cauterization unevenness) occurs in the circumferential direction of the balloon. occured.

The present invention has been made based on the circumstances as described above.
An object of the present invention is to provide a balloon-type electrode catheter capable of uniformly cooling the inside of the balloon in the circumferential direction of the balloon.

(1) A balloon-type electrode catheter of the present invention is a balloon-type electrode catheter for performing high-frequency ablation treatment,
an outer tube having a central lumen and at least four sub-lumens arranged therearound;
a current-carrying connector arranged on the base end side of the outer tube;
It has an expanding portion that expands and contracts and neck portions that are continuous to both ends thereof, the proximal neck portion being fixed to the distal end portion of the outer tube, and the expanding portion enclosing the distal end portion of the outer tube. a balloon connected to the distal end side of the outer tube;
an inner shaft that is inserted through the central lumen of the outer tube, extends into the balloon from the opening of the central lumen, is fixed to a distal neck portion of the balloon, and extends to the outside of the balloon;
a surface electrode made of a thin metal film formed on the outer surface of the balloon at least in the expanded portion of the balloon;
a conducting wire that electrically connects the surface electrode and the current-carrying connector;
at least two of the sub-lumens of the outer tube are fluid-supplying sub-lumens for circulating a cooling fluid to be supplied to the inside of the balloon;
at least two of the sub-lumens of the outer tube are fluid-discharging sub-lumens for circulating the cooled fluid discharged from the inside of the balloon;
The outer tube is formed with an opening for the fluid supply sub-lumen on the distal end side of the intermediate position of the extension portion, and an opening for the fluid discharge sub-lumen is formed near the proximal end of the extension portion. formed,
When the outer tube is longitudinally divided into two on an arbitrary virtual plane passing through the central axis of the outer tube, the fluid supply sub-lumen and the fluid discharge sub-lumen are seen in the cross-sectional view of each divided portion. The feature is that the area ratio to the sublumen is always in the range of 40:60 to 60:40.

According to the balloon-type electrode catheter having such a configuration, the opening of the fluid supply sub-lumen is formed on the tip side of the intermediate position in the axial direction of the expanded portion of the balloon, and the opening of the fluid discharge sub-lumen is formed on the expanded portion. In other words, the fluid supply port to the interior of the balloon and the fluid discharge port from the interior of the balloon are axially displaced from each other, thereby expanding the balloon. Later (after the inside is filled with fluid), a fluid flow is formed from the distal end side to the proximal end side inside the balloon, and the fluid can flow in the axial direction inside the balloon. The tissue inside the balloon and thus surrounding the surface electrodes can be sufficiently cooled.
Further, when the outer tube is longitudinally divided into two by an arbitrary virtual plane passing through the central axis of the outer tube, the fluid supply sub-lumen and the fluid supply sub-lumen are seen in the cross-sectional view of each divided part. Since the area ratio to the lumen is always in the range of 40:60 to 60:40, the total area ratio of the fluid supply sub-lumen and the fluid supply sub-lumen in the outer tube is 40:60 to 60:40. Since the fluid-supplying sub-lumens and the fluid-supplying sub-lumens are not ubiquitous on either half-circumferential side of the balloon in the circumferential direction, The fluid flow can be uniform in the circumferential direction of the balloon, thereby cooling the interior of the balloon uniformly in the circumferential direction.

(2) In the balloon electrode catheter of the present invention, the outer tube is a circular multi-lumen tube over its entire length,
the opening of the fluid supply sub-lumen is formed on the distal end surface of the outer tube,
It is preferable that the opening of the fluid discharge sub-lumen is formed on the outer peripheral surface of the outer tube.

According to the balloon-type electrode catheter having such a configuration, the outer tube including the distal end portion extending inside the balloon has a circular tube shape, so that the flow path of the fluid inside the balloon (the inner peripheral surface of the balloon and the Since the flow path partitioned by the outer peripheral surface of the outer tube) is formed uniformly in the circumferential direction, the flow of the fluid from the distal side to the proximal side inside the balloon is more uniform in the circumferential direction of the balloon. can be

(3) In the balloon electrode catheter of (2) above, it is preferable that the fluid supply sub-lumens and the fluid discharge sub-lumens are alternately arranged along the circumferential direction of the outer tube. .

According to the balloon-type electrode catheter having such a configuration, it is possible to reliably prevent the fluid-supplying sub-lumen and the fluid-supplying sub-lumen from being omnipresent on either half-circumference side of the balloon in the circumferential direction. .

(4) In the balloon electrode catheter of the present invention, it is preferable that the number of the fluid supply sub-lumens and the number of the fluid discharge sub-lumens are 2 to 5, respectively.

According to the balloon-type electrode catheter having such a configuration, the number of the fluid supply sub-lumens and the number of the fluid discharge sub-lumens is two or more. The sub-lumens can be opposed, and two fluid discharge sub-lumens can be opposed.
Further, since the number of the fluid supply sub-lumens and the number of the fluid discharge sub-lumens are each 5 or less, the resistance of the fluid flowing through the lumens (pipe resistance) can be kept low, and a sufficient flow rate can be ensured.

(5) In the balloon electrode catheter of the present invention, the circumferential direction range is 0° to 90° and the circumferential direction is 180° to 270°, with an arbitrary circumferential position of the outer tube as a reference (0°). one or more fluid ejection sub-lumens are formed in each of the ranges;
One or more fluid supply sub-lumens are preferably formed in each of the circumferential range of 90° to 180° and the circumferential range of 270° to 360°.

(6) In the balloon electrode catheter of (2) above, the fluid discharge sub-lumen having an opening on the outer peripheral surface of the outer tube may extend to the distal end of the outer tube and open at the distal end surface. .

According to the balloon-type electrode catheter having such a configuration, the outer tube can be configured with a multi-lumen tube having the same lumen structure over the entire length.
In addition, since the opening of the fluid discharge sub-lumen is formed on the outer peripheral surface of the outer tube, it is substantially possible to prevent the fluid from flowing into the fluid discharge sub-lumen from the opening formed on the distal end surface of the outer tube. can be prevented.

(7) In the balloon electrode catheter of (6) above, the opening of the fluid discharge sub-lumen formed on the outer peripheral surface of the outer tube corresponds to the fluid discharge sub-lumen formed on the distal end surface. It is preferably larger in area than said opening of the lumen.

According to the balloon-type electrode catheter having such a configuration, the fluid is efficiently allowed to flow into the fluid discharge sub-lumen from the opening formed on the outer peripheral surface of the outer tube, and the sub-lumen is formed on the distal end surface of the outer tube. Inflow from the opening can be effectively prevented.

(8) In the balloon electrode catheter of (6) above, the opening of the fluid discharge sub-lumen on the distal end surface of the outer tube may be closed.

According to the balloon-type electrode catheter having such a configuration, it is possible to reliably prevent the inflow of fluid from the opening of the fluid discharge sub-lumen formed on the distal end surface of the outer tube.

According to the balloon-type electrode catheter of the present invention, the inside of the balloon and, by extension, the tissue around the surface electrode can be sufficiently cooled, and the inside of the balloon is uniformly cooled in the circumferential direction of the balloon. be able to.

1 is a plan view of a balloon-type electrode catheter according to a first embodiment of the present invention; FIG. FIG. 2 is a partially broken front view of the balloon electrode catheter shown in FIG. 1 (a front view including the II-II cross section in FIG. 1); FIG. 2 is a plan view (detailed view of section III in FIG. 1) showing the tip portion of the balloon electrode catheter shown in FIG. 1; FIG. 4 is a sectional view along IV-IV in FIG. 3; FIG. 4 is a cross-sectional view taken along line VV of FIG. 3; FIG. 5 is a partially enlarged view (cross-sectional view of an outer tube) of FIG. 4; FIG. 5 is a partially enlarged view (cross-sectional view of an outer tube) of FIG. 4; FIG. 5 is a partially enlarged view (cross-sectional view of an outer tube) of FIG. 4; FIG. 10 is a plan view showing the tip portion of a balloon-type electrode catheter according to a second embodiment of the present invention; FIG. 8 is a cross-sectional view taken along line VIII-VIII of FIG. 7; FIG. 8 is a cross-sectional view taken along line IX-IX of FIG. 7; FIG. 9 is a partially enlarged view of FIG. 8 (cross-sectional view of an outer tube); FIG. 9 is a partially enlarged view of FIG. 8 (cross-sectional view of an outer tube); 2 is a cross-sectional view of an outer tube that constitutes the balloon-type electrode catheter described in Patent Document 2. FIG. 2 is a cross-sectional view of an outer tube that constitutes the balloon-type electrode catheter described in Patent Document 2. FIG.

<First Embodiment>
The balloon-type electrode catheter 100 of this embodiment, shown in FIGS. 1-6, is a balloon-type electrode that is introduced intravascularly to treat focal tissue, such as tumors, in or around a vessel by high-frequency ablation. a catheter.

This balloon-type electrode catheter 100 comprises a circular tubular outer tube 10 having a central lumen 10L and sub-lumens 101L to 112L arranged therearound; and an electrical connector 21 arranged on the proximal end side of the outer tube 10. a fluid supply connector 22 arranged on the proximal end side of the outer tube 10; a fluid discharge connector 23 arranged on the proximal end side of the outer tube 10; The proximal neck portion 35 is fixed to the distal end portion of the outer tube 10, and the extended portion 31 includes the distal end portion of the outer tube 10. a balloon 30 connected to the distal end side of the outer tube 10; and a guide wire lumen, which is inserted through the central lumen 10L of the outer tube 10 and extends from the opening of the central lumen 10L to the inside of the balloon 30. and a lumen (guide wire lumen) that communicates with the guide wire lumen of the inner tube 41, is connected to the distal end of the inner tube 41 inside the balloon 30, and is connected to the distal neck portion 33 A distal tip 46 fixed to and extending outside the balloon 30
strip electrodes 51 to 54 (surface electrodes) made of metal thin films formed on the outer surfaces of the expanded portion 31 and the distal neck portion 33 of the balloon 30; and strip electrodes 51 attached to the distal neck portion 33 of the balloon 30 to 54 are fixed to the outer peripheral surface thereof, the metal ring 60 is electrically connected to each of the strip electrodes 51 to 54; and the tip is connected to the inner peripheral surface of the metal ring 60. , the conducting wire 70 extending to the inside of the balloon 30 and the sub-lumen 106L of the outer tube 10, and having its proximal end connected to the electrical connector 21; ) is embedded, extends to the tube wall of the extension portion 31 and the proximal neck portion 35 and the sub-lumen 112L of the outer tube 10, and has its proximal end connected to the electrical connector 21, a temperature sensor (thermocouple) 80 The sub-lumens 102L, 104L, 107L, 109L, and 111L of the outer tube 10 communicate with the fluid supply connector 22, respectively, so that cooling fluid supplied to the inside of the balloon 30 is provided. The sub-lumens 101L, 103L, 105L, 108L and 110L of the outer tube 10 are fluid supply sub-lumens for circulating the fluid. The outer tube 10 has sub-lumens 101L to 112L on its distal end surface 12 located on the distal end side of the intermediate position of the extended portion 31. Openings are formed, and openings of the fluid discharge sub-lumens 101L, 103L, 105L, 108L and 110L are formed on the outer peripheral surface of the extended portion 31 located near the proximal end thereof;
When the outer tube 10 is longitudinally divided into two on an arbitrary imaginary plane passing through the central axis of the outer tube 10, a fluid supply sub-lumen and a fluid discharge sub-lumen are seen in a cross-sectional view of each divided portion. The area to lumen ratio is always in the range of 40:60 to 60:40.

1 and 2, 20 is a Y connector connected to the proximal end of the outer tube 10, 24 is a guide wire connector, 26 is a wire protection tube, 27 is a fluid supply tube, and 28 is a fluid discharge tube. be.

The outer tube 10 constituting the balloon-type electrode catheter 100 is a circular tube having a central lumen 10L and 12 sub-lumens 101L to 112L arranged at equiangular (30°) intervals around the central lumen 10L.
Each of the sub-lumens 101L to 112L is formed by a lumen tube surrounding it, and these lumen tubes are fixed by the binder resin forming the outer tube 10. As shown in FIG.

Each of the sub-lumens 101L to 112L opens at the distal end surface 12 of the outer tube 10.

Each of the sub-lumens 102L, 104L, 107L, 109L and 111L communicates with the fluid supply connector 22 shown in FIGS.
As a result, the sub-lumens 102L, 104L, 107L, 109L and 111L become "fluid-supplying sub-lumens" for supplying fluid to the inside of the balloon 30 (expansion portion 31).
Here, physiological saline can be exemplified as the fluid supplied inside the balloon 30 .

Each of the sub-lumens 101L, 103L, 105L, 108L and 110L communicates with the fluid discharge connector 23 shown in FIGS.
As a result, the sub-lumens 101L, 103L, 105L, 108L and 110L become "fluid discharge sub-lumens" for discharging the fluid supplied to the inside of the balloon 30 (expansion portion 31) from the inside of the balloon 30. FIG.

The fluid discharge sub-lumens 101L, 103L, 105L, 108L, and 110L are respectively open at the distal end surface 12 of the outer tube 10 and, as shown in FIGS. The outer peripheral surface of the outer tube 10 located in the vicinity of the end (inside the proximal end cone portion 315) is also open.
Here, the opening formed on the outer peripheral surface of the outer tube 10 has a larger area than the opening formed on the distal end surface 12 of the outer tube 10 .

Since an opening is formed in the outer peripheral surface of the outer tube 10 located near the proximal end of the expanded portion 31 of the balloon 30, the fluid discharge sub-lumen 101L, It is possible to substantially prevent fluid from flowing into 103L, 105L, 108L and 110L, which has been confirmed by experiments.

The constituent material of the outer tube 10 is not particularly limited, but examples thereof include polyamide-based resins such as polyamide, polyether polyamide, polyether block amide (PEBAX (registered trademark)), and nylon. Of these, PEBAX is preferred.

The outer diameter of the outer tube 10 (the outer diameter at the base end portion, which will be described later) is usually 1.0 to 3.3 mm, and a preferred example is 1.45 mm.
The diameter of the central lumen 10L of the outer tube 10 is usually 0.35 to 0.95 mm, preferably 0.85 mm.
The diameter of the sub-lumens 101L to 112L of the outer tube 10 is normally 0.10 to 0.75 mm, and a preferred example is 0.25 mm.
The length of the outer tube 10 is usually 100-2200 mm, and a preferred example is 1800 mm.

As shown in FIGS. 1 and 2, a Y connector 20 is connected to the proximal end of the outer tube 10 .
A lumen tube surrounding the sub-lumens 101L to 105L and the sub-lumens 107L to 111L of the outer tube 10 enters the inside of the Y connector 20 from the proximal end of the outer tube 10 .

The proximal end of the lumen tube surrounding the sub-lumens 102L, 104L, 107L, 109L and 111L (fluid-supplying sub-lumens) is connected to the single-lumen-structured fluid-supplying tube 27 inside the Y connector 20 (using an adhesive). fixed by The fluid supply tube 27 extends outside the Y connector 20 , and the proximal end of the fluid supply tube 27 is connected to the fluid supply connector 22 .

The base ends of the lumen tubes surrounding the sub-lumens 101L, 103L, 105L, 108L and 110L (fluid discharge sub-lumens) are connected to the single-lumen structure fluid discharge tube 28 inside the Y connector 20 (using an adhesive). fixed by The fluid discharge tube 28 extends outside the Y connector 20 , and the proximal end of the fluid discharge tube 28 is connected to the fluid discharge connector 23 .

The balloon 30 constituting the balloon-type electrode catheter 100 includes an expanding portion 31 that expands and contracts, a distal neck portion 33 that continues to the distal end of the expanding portion 31, and a proximal neck portion 35 that continues to the proximal end of the expanding portion 31. It is composed of

The expanded portion 31 of the balloon 30 is a space-forming portion that expands when fluid is supplied to its interior and contracts when the fluid is discharged from its interior.
The expansion portion 31 of the balloon 30 includes a cylindrical portion 311, a distal cone portion 313 extending from the distal end of the cylindrical portion 311 to the proximal end of the distal neck portion 33, and a proximal end of the cylindrical portion 311 to the proximal neck portion. and a proximal cone portion 315 extending to the distal end of the portion 35 .

The balloon 30 is connected to the distal end of the outer tube 10 by fixing the proximal neck portion 35 to the distal end of the outer tube 10 and enclosing the distal end of the outer tube 10 in the expanded portion 31 . ing.

The distal end surface 12 of the outer tube 10 is positioned near the distal end of the cylindrical portion 311 that is distal to the intermediate position of the expanded portion 31 of the balloon 30 in the axial direction.
As a result, the fluid flowing through the fluid supply sub-lumens 102L, 104L, 107L, 109L, and 111L is discharged in the distal direction from each opening positioned near the distal end of the cylindrical portion 311, and the discharged fluid expands. It can reach the vicinity of the distal end of the portion 31 (distal cone portion 313), thereby forming a fluid flow from the distal side to the proximal side inside the balloon 30 (expansion portion 31).

When the opening position of the fluid supply sub-lumen is on the proximal side of the intermediate position in the axial direction of the expanded portion of the balloon, even if the fluid is discharged in the distal direction from the opening after the balloon is expanded, The fluid cannot reach the vicinity of the distal end of the balloon, and a flow of the fluid from the distal end side to the proximal end side cannot be formed inside the balloon.

The constituent material of the balloon 30 is not particularly limited, and the same materials as the balloon constituting the conventionally known balloon catheter can be used. For example, polyamide such as polyamide, polyether polyamide, PEBAX and nylon Polyurethane resins such as thermoplastic polyether urethane, polyether polyurethane urea, fluorine polyether urethane urea, polyether polyurethane urea resin and polyether polyurethane ureaamide.

The diameter of the balloon 30 (expansion portion 31) is normally 0.70 to 30.0 mm, and a preferred example is 2.0 mm.
The outer diameter of the proximal neck portion 35 of the balloon 30 is substantially equal to the outer diameter of the proximal end portion of the outer tube 10, and is usually 1.0 to 3.3 mm, and a preferred example is 1.45 mm. is.
The length of the balloon 30 (expansion portion 31) is normally 8 to 50 mm, and a preferred example is 20 mm.

In the balloon electrode catheter 100 of this embodiment, the inner tube 41 and the distal tip 46 constitute an inner shaft.
The inner tube 41 constituting the balloon-type electrode catheter 100 has a lumen through which a guidewire can be inserted (guidewire lumen), is inserted through the central lumen 10L of the outer tube 10, and has its distal end opening in the central lumen 10L. extends into the balloon 30 (expansion portion 31).

The distal end portion of the inner tube 41 extending inside the balloon 30 extends inside the cylindrical portion 311 of the expanded portion 31 and is connected to the distal tip 46 inside the cylindrical portion 311 .

On the other hand, the proximal end of the inner tube 41 enters the inside of the Y connector 20 from the proximal end of the outer tube 10 (the opening on the proximal side of the central lumen 10L), extends inside the Y connector 20, It extends outside the connector 20 , and the proximal end of the inner tube 41 is connected to the guide wire connector 24 .

As the material for forming the inner tube 41, the same material as the inner tube constituting a conventionally known balloon catheter can be used. ketone resins) are preferred.

The outer diameter of the inner tube 41 is the same as or slightly smaller than the diameter of the central lumen 10L of the outer tube 10 through which it is inserted, and is usually 0.34 to 0.99 mm, and a preferred example is 0.84 mm. It is said that
The inner diameter of the inner tube 41 is normally 0.31 to 0.92 mm, preferably 0.68 mm.

The distal tip 46 constituting the balloon-type electrode catheter 100 has a lumen (guidewire lumen) that communicates with the guidewire lumen of the inner tube 41, and includes a cylindrical portion 311 and a distal cone portion 313 of the expanded portion 31 of the balloon 30. and is fixed to the distal neck portion 33 and extends outside the balloon 30 .

The constituent material of the distal tip 46 is not particularly limited, but examples include polyamide resins such as polyamide, polyether polyamide, PEBAX and nylon, and polyurethane.

The inner diameter of the distal tip 46 is substantially the same as the inner diameter of the inner tube 41, usually 0.31 to 0.92 mm, preferably 0.68 mm.
The outer diameter of the distal tip 46 is normally 0.35 to 2.6 mm, and a preferred example is 1.0 mm.
The outer diameter of the distal neck portion 33 of the balloon 30 to which the distal tip 46 is fixed is usually 0.37 to 3.3 mm, and a preferred example is 1.18 mm.

On the outer surface of the balloon 30 (cylindrical portion 311 and distal cone portion 313 of the expansion portion 31 and distal neck portion 33), surface electrodes to which a high-frequency current is applied are provided so as to extend along the axial direction of the balloon 30. Strip electrodes 51 to 54 formed of metal thin films are arranged along the circumferential direction of the balloon 30 at intervals of 90°.

Examples of materials for forming the thin metal films forming the strip electrodes 51 to 54 include gold, platinum, silver, copper, alloys thereof, and stainless steel.
The film thickness of the thin metal films forming the strip electrodes 51 to 54 is preferably 0.5 to 5 μm, more preferably 1.0 to 2.5 μm.
If this film thickness is too small, the temperature of the metal thin film may rise to a high temperature due to Joule heat during the procedure (during high-frequency current application).
On the other hand, if the film thickness of the thin film is too large, the metal thin film will be less likely to follow the change in shape of the balloon that accompanies expansion and contraction, which may impair the expansion/contraction properties of the balloon.

The method of forming the metal thin films constituting the strip electrodes 51 to 54 on the outer surface of the balloon 30 is not particularly limited, and ordinary metal thin film forming methods such as vapor deposition, sputtering, plating, and printing can be employed. can.

A metal ring 60 is attached to the distal neck portion 33 of the balloon 30 . The ends of the strip electrodes 51 to 54 are fixed to the outer peripheral surface of the metal ring 60 . Thereby, each of the strip electrodes 51 to 54 and the metal ring 60 are electrically connected.

Examples of the constituent material of the metal ring 60 include platinum and platinum-based alloys.

The inner diameter of the metal ring 60 attached to the distal neck portion 33 is substantially the same as the outer diameter of the distal neck portion 33, and is usually 0.37 to 3.3 mm. .18 mm.
The outer diameter of the metal ring 60 attached to the distal neck portion 33 is smaller than the outer diameters of the outer tube 10 and the proximal neck portion 35, and is usually 0.98 to 3.28 mm. is 1.32 mm.

A leading end of a conducting wire 70 is fixed to the inner peripheral surface of the metal ring 60 .
This conducting wire 70 extends inside the tube wall of the distal tip 46, extends inside the expanded portion 31 of the balloon 30 along the inner tube 41, extends to the sub-lumen 106L of the outer tube 10, and is connected to the Y connector. 20 and extends from the Y connector 20 through the interior of a conductor protection tube 26 extending from the Y connector 20 .

The base end of the conducting wire 70 is connected to the electrical connector 21 . The electrical connector 21 has both a function as a connector for conducting a high-frequency current to each of the strip electrodes 51 to 54 and a function as a thermocouple connector for connecting a temperature sensor 80 to a temperature measuring instrument, which will be described later. ing.

By connecting each of the strip electrodes 51 to 54 to the electrical connector 21 via the metal ring 60 and the lead wire 70, a high frequency current can be applied to each of the strip electrodes 51 to 54 evenly.

Examples of the constituent material of the conducting wire 70 include copper, silver, gold, platinum, tungsten, and alloys of these metals, and it is preferable that an electrically insulating protective coating such as fluororesin is applied.

A temperature sensor 80 consisting of a thermocouple is embedded in the tube wall of the balloon 30 . A side temperature portion 81 (temperature measuring junction) of the temperature sensor 80 is located on the pipe wall of the extension portion 31 .

The temperature sensor 80 enters the sub-lumen 112L of the outer tube 10 from the tube wall of the proximal neck portion 35 of the balloon 30, extends into the sub-lumen 112L, and extends inside the Y connector 20 together with the conducting wire 70. , and extends from the Y connector 20 through the inside of the conductor protection tube 26 extending from the Y connector 20 .
A proximal end of the temperature sensor 80 is connected to the electrical connector 21 .

In the balloon electrode catheter 100 of the present embodiment, when the outer tube 10 is longitudinally divided into two on any virtual plane passing through the central axis of the outer tube 10, in the cross-sectional view of each divided portion , the area ratio of the fluid supply sub-lumen to the fluid discharge sub-lumen is always in the range of 40:60 to 60:40.

For example, as shown in FIG. 6A, when the outer tube 10 is divided into two parts (10A1 and 10A2) on the imaginary plane P1, in the part 10A1, sub-lumens for fluid supply (102L, 104L) and sub-lumens for fluid discharge (102L, 104L) The area ratio with the lumens (101L, 103L, 105L) is 40:60, and in the portion 10A2, the sub-lumen for fluid supply (1
07L, 109L, 111L) and the fluid discharge sub-lumens (108L, 110L) are 60:40.

Further, as shown in FIG. 6B, when the outer tube 10 is divided into two parts (10B1 and 10B2) on the imaginary plane P2, in the part 10B1, fluid supply sub-lumens (102L, 109L, 111L) and fluid discharge sub-lumens (102L, 109L, 111L) The area ratio of the fluid supply sub-lumens (101L, 110L) is 60:40. It becomes 40:60.

Furthermore, as shown in FIG. 6C, when the outer tube 10 is divided into two parts (10C1 and 10C2) on the imaginary plane P3, the fluid supply sub-lumen and the fluid discharge sub-lumen are formed in the parts 10C1 and 10C2. area ratio is 50:50.

Thus, when the outer tube 10 is divided along the virtual plane passing through its central axis, the area ratio between the fluid supply sub-lumen and the fluid discharge sub-lumen in the cross-sectional view of each divided portion is always 40:60. ∼60:40, the total area ratio of the fluid supply sub-lumen and the fluid supply sub-lumen in the outer tube 10 is in the range of 40:60 to 60:40, and the fluid supply sub-lumen Since the lumens and fluid supply sub-lumens are arranged without being ubiquitous in the circumferential direction of the outer tube 10, the fluid flow (flow rate) from the distal side to the proximal side inside the balloon 30 can be controlled by the balloon. 30 can be uniform in the circumferential direction.

On the other hand, as shown in FIG. 11A, when the outer tube 1 constituting the balloon electrode catheter described in Patent Document 2 is divided into two parts (1A1 and 1A2) along a virtual plane P4, the part 1A1 and in the portion 1A2, the area ratio between the fluid supply sub-lumen 2 and the fluid discharge sub-lumen 3 is 50:50.
However, as shown in FIG. 11B, when this outer tube 1 is divided into two parts (1B1 and 1B2) on a virtual plane P5, the area of the fluid supply sub-lumen 2 and the fluid discharge sub-lumen 3 in the part B1 is The ratio is 0:100, the area ratio of the fluid supply sub-lumen 2 and the fluid discharge sub-lumen 3 in the portion 1B2 is 100:0, the fluid supply sub-lumen 2 is ubiquitous in the portion 1B2, and the fluid discharge sub-lumen 2 is ubiquitous in the portion 1B2. Sublumens 3 are ubiquitous in portion 1B1. With a balloon electrode catheter having such an outer tube 1, it is not possible to make the flow (flow rate) of the fluid from the distal end to the proximal end of the balloon uniform in the circumferential direction of the balloon. .

According to the balloon-type electrode catheter 100 of the present embodiment, each of the band-shaped electrodes 51 to 54 formed on the outer surface of the balloon 30 can perform high-frequency ablation treatment over a wide range on a lesion in or around a vessel. can.

Further, each of the fluid supply sub-lumens 102L, 104L, 107L, 109L and 111L opens at the distal end surface 12 of the outer tube 10 located near the distal end of the cylindrical portion 311 of the expanded portion 31 of the balloon 30 to discharge the fluid. Each of the sub-lumens 101L, 103L, 105L, 108L, and 110L is open on the outer peripheral surface of the outer tube 10 located near the proximal end of the expanded portion 31 (inside the proximal-side cone portion 315). , even after the balloon 30 is expanded (after the inside is filled with fluid), a fluid flow can be formed from the distal side to the proximal side inside the balloon 30, and the fluid can flow. be able to.

In particular, fluid supply sub-lumens 102L, 104L, 107L, 109L and 111
The fluid discharged in the distal direction from the opening of L hits the inner wall surface of the distal cone portion 313 of the extension portion 31, and then along the inner wall surfaces of the cylindrical portion 311 and the proximal cone portion 315 of the extension portion 31. The fluid can be circulated inside the balloon 30 (expansion portion 31) by flowing in the proximal direction.

As a result, the inside of the balloon 30 can be efficiently cooled over the entire area of the expanded portion 31, thereby sufficiently cooling the tissue around the strip electrodes 51 to 54, thereby preventing the tissue from fibrosis. can be reliably prevented.

Furthermore, when the outer tube 10 is longitudinally divided into two on an arbitrary imaginary plane passing through the central axis of the outer tube 10, in the cross-sectional view of each divided portion, the fluid supply sub-lumen and the fluid discharge The area ratio to the sub-lumen for the fluid supply is always in the range of 40:60 to 60:40, and the fluid-supplying sub-lumens and the fluid-supplying sub-lumens are arranged without being ubiquitous in the circumferential direction of the outer tube 10. Therefore, the flow (flow rate) of the fluid from the distal side to the proximal side inside the balloon 30 can be made uniform in the circumferential direction of the balloon 30, thereby making the inside of the balloon 30 uniform. Uniform cooling can be achieved in the circumferential direction.

In particular, since the outer tube 10 including the distal end extending inside the balloon 30 has a circular tubular shape, the flow path of the fluid inside the balloon 30 (between the inner peripheral surface of the balloon 30 and the outer peripheral surface of the outer tube 10) ) are formed uniformly in the circumferential direction, so that the fluid flow (flow rate) from the distal side to the proximal side inside the balloon 30 is more uniform in the circumferential direction of the balloon 30. can be

Cases to which the balloon-type electrode catheter 100 of the present embodiment can be applied include tumors and vagus nerves in and around blood vessels, specifically bile duct cancer, lung cancer, liver cancer, kidney cancer, and adrenal adenoma. , renal artery vagus nerve, and the like.

<Second embodiment>
7 is a plan view showing the tip portion of the balloon electrode catheter 200 according to this embodiment, FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 7, FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 10A and 10B are partial enlarged views of FIG. 8 (cross-sectional views of the outer tube).
7 to 9, the same reference numerals are used for the same components as those of the balloon electrode catheter 100 according to the first embodiment.

This balloon-type electrode catheter 200 includes a circular tubular outer tube 15 having a central lumen 15L and sub-lumens 151L to 156L arranged therearound; an electrical connector arranged on the proximal end side of the outer tube 15; A fluid supply connector arranged on the proximal side of the outer tube 15; a fluid discharge connector arranged on the proximal side of the outer tube 15; an expanding portion 31 that expands and contracts; The proximal neck portion 35 is fixed to the distal end portion of the outer tube 15, and the extended portion 31 encloses the distal end portion of the outer tube 15. Thus, the balloon 30 connected to the distal end side of the outer tube 15; has a guide wire lumen, is inserted through the central lumen 15L of the outer tube 15, and extends inside the balloon 30 from the opening of the central lumen 15L. and a lumen communicating with the guide wire lumen of the inner tube 41 (guide wire lumen). a distal tip 46 extending to the outside of the balloon 30; belt-shaped electrodes 51 to 54 (surface electrodes) made of metal thin films formed on the outer surfaces of the expanded portion 31 and the distal neck portion 33 of the balloon 30; a metal ring 60 attached to the distal neck portion 33 and electrically connected to each of the strip electrodes 51 to 54 by fixing the tip portion of each of the strip electrodes 51 to 54 to its outer peripheral surface; a conducting wire 70 whose distal end is connected to the inner peripheral surface of the ring 60, extends to the inside of the balloon 30 and the sub-lumen 156L of the outer tube 15, and whose proximal end is connected to the electrical connector 21; The distal end (temperature measuring portion 81) is embedded in the tube wall of 31, extends to the tube walls of the expanded portion 31, the proximal side neck portion 35, and the sub-lumen 155L of the outer tube 15, and the proximal end is connected to the electrical connector. a temperature sensor (thermocouple) 80 connected thereto; sub-lumens 152L and 154L of the outer tube 15 are fluid-supply sub-lumens communicating with the fluid-supply connector; 15 have sub-lumens 151L and 153L, respectively, which are fluid discharge sub-lumens; Openings of the sub-lumens 151L to 156L are formed on the distal end surface 17 located on the distal side of the intermediate position of the extended portion 31, and the outer peripheral surface located near the proximal end of the extended portion 31 is filled with fluid. Openings of the discharge sub-lumens 151L and 153L are formed; when the outer tube 15 is longitudinally divided into two on any imaginary plane passing through the central axis of the outer tube 15, the cross section of each divided portion Visually, the area ratio between the fluid supply sub-lumen and the fluid discharge sub-lumen is always in the range of 40:60 to 60:40.

The outer tube 15 constituting the balloon-type electrode catheter 100 is a circular tubular tube having a central lumen 15L and sub-lumens 151L to 156L.
The sub-lumens 151L to 154L have substantially elliptical cross-sectional shapes, and the sub-lumens 155L and 156L have circular cross-sectional shapes.
Each of the sub-lumens 151L to 156L is formed by a lumen tube surrounding it, and these lumen tubes are fixed by the binder resin forming the outer tube 15. As shown in FIG.

The sub-lumens 151L to 156L are open at the distal end surface 17 of the outer tube 15, respectively.

Each of the sub-lumens 152L and 154L communicates with a fluid-supply connector, whereby the sub-lumens 152L and 154L are "fluid-supplying sub-lumens" for supplying fluid to the inside of the balloon 30 (expansion portion 31). "Lumen".

Each of the sub-lumens 151L and 153L communicates with a fluid discharge connector, whereby the sub-lumens 151L and 153L discharge the fluid supplied to the inside of the balloon 30 (expansion portion 31) from the inside of the balloon 30. It becomes a "fluid discharge sub-lumen" for

As shown in FIG. 9, the temperature sensor 80 extends to the sub-lumen 155L, and the conducting wire 70 extends to the sub-lumen 156L.

The fluid discharge sub-lumens 151L and 153L are open to the distal end face 17 of the outer tube 15, respectively, and extend near the proximal end (base end side) of the expanded portion 31 of the balloon 30 as shown in FIGS. The outer peripheral surface of the outer tube 15 located inside the cone portion 315 is also open.

Since the opening is formed in the outer peripheral surface of the outer tube 15 located near the proximal end of the expanded portion 31 of the balloon 30, the fluid discharge sub-lumen 151L and the fluid discharge sub-lumen 151L and Fluid can be substantially prevented from flowing into 153L.

As shown in FIG. 8, when the circumferential position of the outer tube 15 in which the sub-lumen 155L is formed is taken as a reference (0°), the fluid discharge sub-lumen 151L is formed in the range of 0° to 90°, A fluid discharge sub-lumen 153L is formed in a range of 180° to 270°, and the fluid discharge sub-lumen 151L and the fluid discharge sub-lumen 153L are arranged to face each other across the central axis of the outer tube 15. .

A fluid supply sub-lumen 152L is formed in the range of 90° to 180°, and a fluid supply sub-lumen 154L is formed in the range of 270° to 360°. The sub-lumen 154</b>L is arranged to face the central axis of the outer tube 15 .

As shown in FIG. 10A, when the outer tube 15 is divided into two parts (15A1 and 15A2) on the imaginary plane P6, both the part 15A1 and the part 15A2 have fluid supply sub-lumens and fluid discharge sub-lumens. is 50:50.

Further, as shown in FIG. 10B, when the outer tube 15 is divided into two parts (15B1 and 15B2) on the imaginary plane P7, both the part 15B1 and the part 15B2 have fluid supply sub-lumens and fluid discharge sub-lumens. The area ratio with the sublumen is 50:50.

Thus, when the outer tube 15 is divided along the virtual plane passing through its central axis, the area ratio between the fluid supply sub-lumen and the fluid discharge sub-lumen in the cross-sectional view of each divided portion is always 50:50. Since the fluid-supplying sub-lumens and the fluid-supplying sub-lumens are arranged without being ubiquitous in the circumferential direction of the outer tube 15, the fluid flows inside the balloon 30 from the distal side to the proximal side. (Flow rate) can be made uniform in the circumferential direction of the balloon 30 . Thereby, the inside of the balloon 30 can be uniformly cooled in its circumferential direction.

Further, since the number of the fluid supply sub-lumens 152L and 154L and the number of the fluid discharge sub-lumens 151L and 153L are two, respectively, the resistance of the fluid flowing through these lumens (intra-tube resistance) can be kept low and sufficient Flow rate can be secured.

REFERENCE SIGNS LIST 100 balloon type electrode catheter 10 outer tube 10L central lumen 102L, 104L, 107L, 109L, 111L sub-lumen for fluid supply 101L, 103L, 105L, 108L, 110L sub-lumen for fluid discharge 106L, 112L sub-lumen 12 tip surface of outer tube 20 Y-connector 21 Electrical connector 22 Fluid supply connector 23 Fluid discharge connector 24 Guide wire connector 26 Conductive wire protection tube 27 Fluid supply tube 28 Fluid discharge tube 30 Balloon 31 Expansion part 311 Cylindrical part 311
313 distal cone portion 313
315 proximal cone portion 315
33 distal side neck portion 35 proximal side neck portion 41 inner tube 46 distal tip 51-54 strip electrodes (surface electrodes)
60 metal ring 70 wire 80 temperature sensor (thermocouple)
81 temperature measuring part 200 balloon type electrode catheter 15 outer tube 15L central lumen 152L, 154L fluid supply sub-lumen 151L, 153L fluid discharge sub-lumen 155L, 156L sub-lumen 17 tip surface of outer tube

Claims (8)

1. A balloon-type electrode catheter for performing high-frequency ablation treatment,
   an outer tube having a central lumen and at least four sub-lumens arranged therearound;
   a current-carrying connector arranged on the base end side of the outer tube;
   It has an expanding portion that expands and contracts and neck portions that are continuous to both ends thereof, the proximal neck portion being fixed to the distal end portion of the outer tube, and the expanding portion enclosing the distal end portion of the outer tube. a balloon connected to the distal end side of the outer tube;
   an inner shaft that is inserted through the central lumen of the outer tube, extends into the balloon from the opening of the central lumen, is fixed to a distal neck portion of the balloon, and extends to the outside of the balloon;
   a surface electrode made of a thin metal film formed on the outer surface of the balloon at least in the expanded portion of the balloon;
   a conducting wire that electrically connects the surface electrode and the current-carrying connector;
   at least two of the sub-lumens of the outer tube are fluid-supplying sub-lumens for circulating a cooling fluid to be supplied to the inside of the balloon;
   at least two of the sub-lumens of the outer tube are fluid-discharging sub-lumens for circulating the cooled fluid discharged from the inside of the balloon;
   The outer tube is formed with an opening for the fluid supply sub-lumen on the distal end side of the intermediate position of the extension portion, and an opening for the fluid discharge sub-lumen is formed near the proximal end of the extension portion. formed,
   When the outer tube is longitudinally divided into two on an arbitrary virtual plane passing through the central axis of the outer tube, the fluid supply sub-lumen and the fluid discharge sub-lumen are seen in the cross-sectional view of each divided portion. A balloon-type electrode catheter, characterized in that the area ratio to the sublumen is always in the range of 40:60 to 60:40.
2. The outer tube is a circular multi-lumen tube over its entire length,
   the opening of the fluid supply sub-lumen is formed on the distal end surface of the outer tube,
   2. The balloon electrode catheter according to claim 1, wherein the opening of the fluid discharge sub-lumen is formed on the outer peripheral surface of the outer tube.
3. The balloon electrode catheter according to claim 2, wherein the fluid supply sub-lumens and the fluid discharge sub-lumens are alternately arranged along the circumferential direction of the outer tube.
4. The balloon electrode catheter according to any one of claims 1 to 3, wherein the number of said fluid supply sub-lumens and said fluid discharge sub-lumens is 2 to 5, respectively.
5. One or two or more fluid discharge sub-lumens are formed in each of a range of 0° to 90° and a range of 180° to 270° with an arbitrary circumferential position of the outer tube as a reference (0°),
   4. The fluid supply sub-lumen according to any one of claims 1 to 3, characterized in that one or two or more of the fluid supply sub-lumens are formed in each of the range of 90° to 180° and the range of 270° to 360°. Balloon electrode catheter.
6. The balloon-type electrode catheter according to claim 2, wherein the fluid discharge sub-lumen extends to the distal end of the outer tube and is also open at the distal end surface.
7. The opening of the fluid discharge sub-lumen formed on the outer peripheral surface of the outer tube has a larger area than the opening of the fluid discharge sub-lumen formed on the tip end surface. The balloon-type electrode catheter according to claim 6.
8. The balloon-type electrode catheter according to claim 6, wherein the opening of the fluid discharge sub-lumen on the distal end surface of the outer tube is closed.

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