WO2022176013A1

WO2022176013A1 - Catheter

Info

Publication number: WO2022176013A1
Application number: PCT/JP2021/005696
Authority: WO
Inventors: 綾季星田
Original assignee: 日本ライフライン株式会社
Priority date: 2021-02-16
Filing date: 2021-02-16
Publication date: 2022-08-25
Also published as: JPWO2022176013A1

Abstract

A catheter according to one embodiment of the present invention is for measuring the internal temperature of hollow organs inside the body and comprises: a catheter shaft that extends along the axial direction and has a lumen for circulation of fluid; a handle that is attached to the base end side of the catheter shaft; a flat balloon that is provided to the leading end side of the catheter shaft, is configured so as to be capable of being expanded by the fluid, and has mutually facing first and second surfaces; and a plurality of temperature sensors that are arranged in a planar configuration on the first surface side of the balloon. The balloon is configured to be capable of, even when being expanded, expanding in a flat shape. One or more conductors that contribute to temperature measurement by the temperature sensors are provided in regions between the respective temperature sensors on the first surface side of the balloon.

Description

catheter

The present invention relates to a catheter used for measuring the internal temperature of hollow organs in the body such as the esophagus.

As one of the treatment methods for arrhythmia, for example, an operation is performed to ablate the arrhythmic part inside the heart using an ablation catheter. This cauterization technique is generally divided into a technique of high-temperature ablation (heating) using high-frequency current and a technique of low-temperature ablation (cooling) using liquefied nitrous oxide, liquid nitrogen, or the like. When such ablation catheters are used to ablate, for example, the posterior left atrial wall of the heart (during left atrial ablation procedures), the esophagus adjacent to the posterior left atrial wall is generally also heated or cooled, may be damaged.

Therefore, a technique has been proposed to measure (monitor) information about the temperature inside the esophagus (inner wall) by inserting a temperature-measuring catheter (a so-called esophageal catheter) into the esophagus through the patient's nose (using a transnasal approach). (See, for example, Patent Document 1). By monitoring the temperature inside the esophagus in this way, it is possible to avoid the risk of the esophagus being damaged during, for example, the above-described left atrial ablation surgery.

Japanese Patent Application Publication No. 2010-505592

By the way, such a catheter for temperature measurement is generally required to improve the measurement accuracy when measuring temperature. It would be desirable to provide a catheter capable of improving measurement accuracy when measuring temperature.

A catheter according to one embodiment of the present invention is a catheter for measuring the internal temperature of a hollow organ in the body, comprising a catheter shaft extending along an axial direction and having a fluid communication lumen; A handle attached to the proximal end of the shaft, and a flattened balloon provided on the distal end of the catheter shaft, configured to be expandable by the fluid, and having a first surface and a second surface facing each other. and a plurality of temperature sensors arranged planarly on the first surface side of the balloon. The balloon is configured to be flattened and expandable even during expansion. In addition, on the first surface side of the balloon, one or more conductors are provided in regions between the plurality of temperature sensors, which contribute to temperature measurement by the temperature sensors.

In a catheter according to an embodiment of the present invention, in a state in which a flat balloon is flattened (inflated) inside a hollow organ, a plurality of flat balloons are arranged planarly on the first surface side of the balloon. A temperature sensor measures the temperature. As a result, the internal temperature of the hollow organ can be grasped two-dimensionally, and the temperature of the site to be monitored can be measured more reliably. Also, the one or more conductors are provided in a region between the plurality of temperature sensors on the first surface side of the flat balloon. As a result, the heat in the area between such temperature sensors (the area where no temperature sensor is located) is effectively transferred to the temperature sensor via the conductor, resulting in more accurate temperature measurement (temperature distribution measurement) will be performed.

In the catheter according to one embodiment of the present invention, the conductor portion may include a plurality of leg portions each extending from the vicinity of the temperature sensor toward the distance on the first surface side of the balloon. good. In this case, the heat at a distance from the temperature sensor is easily transmitted to the vicinity of the temperature sensor through the plurality of legs, so that the temperature distribution can be measured with higher accuracy. The measurement accuracy at the time of is further improved.

In this case, the plurality of legs may be arranged substantially isotropically around the temperature sensor. In this case, the heat around the temperature sensor is transmitted to the temperature sensor via the plurality of legs arranged substantially isotropically, resulting in a more accurate measurement of the temperature distribution. , the measurement accuracy in temperature measurement is further improved.

Also, the conductor portion including the plurality of leg portions may be individually arranged corresponding to each of the plurality of temperature sensors. In this case, in each of the plurality of temperature sensors, heat is effectively transmitted via the conductor portion including the plurality of legs, so that the temperature distribution of the entire plurality of temperature sensors can be measured more accurately. It will be well done. As a result, the measurement accuracy in temperature measurement is further improved. Moreover, the conductor portion may have high thermal conductivity, which is higher than other regions between the temperature sensors. In this case, the heat is more easily transmitted to the temperature sensor via the conductor having such high thermal conductivity, so that the temperature distribution can be measured with higher accuracy. will be further improved.

In the catheter according to one embodiment of the present invention, the handle is a flat handle, and the orientation of the plane formed by the flat handle is the orientation of the plane formed by the flat balloon; You may make it substantially match|coincide. In this case, even when the flattened balloon is inserted into the hollow organ, the orientation of the plane formed by the balloon can be easily changed using the orientation of the plane formed by the flattened handle. be able to comprehend. As a result, the convenience of using the catheter is improved.

The hollow organ in the body includes, for example, the esophagus. In this case, the catheter according to one embodiment of the present invention can be configured as a catheter used for measuring the internal temperature of the esophagus during left atrial ablation surgery on a patient.

According to the catheter according to one embodiment of the present invention, the one or more conductors are provided in the region between the plurality of temperature sensors on the first surface side of the flat balloon. Accurate temperature measurements can be made. Therefore, it is possible to improve the measurement accuracy when measuring the temperature.

1 is a front view showing a schematic configuration example of a catheter according to an embodiment of the present invention; FIG. FIG. 2 is a front view showing an enlarged configuration example of the vicinity of the distal end portion of the catheter shown in FIG. 1; FIG. 3 is a side view showing a configuration example of the vicinity of the distal end portion of the catheter shown in FIG. 2; FIG. 3 is a rear view showing a configuration example of the vicinity of the distal end portion of the catheter shown in FIG. 2; 3 is a cross-sectional view taken along line VA-VA shown in FIG. 2; FIG. 3 is a cross-sectional view taken along line VB-VB shown in FIG. 2; FIG. FIG. 3 is a cross-sectional view taken along the line VC-VC shown in FIG. 2; It is sectional drawing which expands and represents the VI part shown in FIG. 5C. FIG. 3 is a cross-sectional view taken along line VII-VII shown in FIG. 2; FIG. 5 is a rear view showing a detailed configuration example of the balloon shown in FIG. 4; FIG. 2 is a side view showing a detailed configuration example of the handle shown in FIG. 1; FIG. 2 is a front view showing a detailed configuration example of the handle shown in FIG. 1; FIG. 4 is a diagram schematically showing a state in which the distal end portion of the temperature-measuring catheter according to Comparative Example 1 is left in the esophagus. FIG. 10 is a diagram schematically showing a state in which the distal end portion of the temperature-measuring catheter according to Comparative Example 2 is left in the esophagus. FIG. 11 is a rear view showing a detailed configuration example of a balloon in a catheter according to a modification;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The description will be given in the following order.
1. Embodiment (an example of a catheter used for measuring the internal temperature of the esophagus)
2. Modifications (modifications related to the shape of the conductor)
3. Other variations

<1. Embodiment>
[A. Outline configuration]
FIG. 1 is a schematic front view (ZX front view) of a schematic configuration example of a catheter (catheter 1) according to one embodiment of the present invention. FIG. 2 is an enlarged front view (ZX front view) of a configuration example of the vicinity of the distal end portion of the catheter 1 shown in FIG. FIG. 3 is a side view (YZ side view) showing an example of the configuration near the tip of the catheter 1 shown in FIG. 2, and FIG. 4 is the tip of the catheter 1 shown in FIG. A rear view (ZX rear view) shows an example of the configuration around the part.

5A is a cross-sectional view (XY cross-sectional view) along the VA-VA line shown in FIG. 2, and FIG. 5B is a cross-sectional view along the VB-VB line shown in FIG. FIG. 5C is a cross-sectional view along the arrow (XY cross-sectional view), and FIG. 5C is a cross-sectional view along the VC-VC line shown in FIG. 2 (XY cross-sectional view). 6 is a cross-sectional view (XY cross-sectional view) showing an enlarged view of the VI portion shown in FIG. 5C, and FIG. 7 is a cross-sectional view along the VII-VII line shown in FIG. (XY sectional view). FIG. 8 is a rear view (ZX rear view) showing a detailed configuration example of the later-described balloon 13 shown in FIG.

This catheter 1 measures information about the internal temperature (inner wall temperature) of a hollow organ (e.g., digestive organ such as the esophagus) in the patient's body during treatment of arrhythmia or the like (e.g., left atrial ablation). It is a catheter (so-called esophageal catheter) used to Specifically, although the details will be described later, the catheter 1 is inserted into the patient's esophagus or the like through the nose (nasal cavity) (using a transnasal approach).

As shown in FIG. 1, the catheter 1 includes a catheter shaft 11 (catheter tube) as a catheter main body (long portion), a handle 12 attached to the proximal end of the catheter shaft 11, and the catheter shaft 11. It has a balloon 13 provided on the distal end side and a fluid injection tube 14 for externally injecting a predetermined fluid L, which will be described later.

(catheter shaft 11)
The catheter shaft 11 is made of a tubular structure (hollow tubular member) having flexibility, and has a shape extending along its own axial direction (Z-axis direction) (see FIG. 1). Specifically, the axial length of the catheter shaft 11 is about several times to several tens of times longer than the axial length (Z-axis direction) of the handle 12 .

Here, as shown in FIG. 1, the catheter shaft 11 has a distal end (flexible distal end portion 11A) configured to be relatively flexible. Further, in the catheter shaft 11, the rigidity in the vicinity of the arrangement area of the balloon 13 described later (near the distal flexible portion 11A described above) is higher than the rigidity in the proximal side.

This catheter shaft 11 also has a so-called multi-lumen structure in which a plurality of lumens (inner holes, pores, through-holes) are formed inside so as to extend along its own axial direction (Z-axis direction). is doing. In the lumen of the catheter shaft 11, various fine wires (lead

wires

50, 51, etc., which will be described later) are respectively inserted in a state of being electrically insulated from each other, or the above-described fluid L is circulated. It has become.

Specifically, as shown in FIGS. 6 and 7, the catheter shaft 11 includes a circulation lumen (so-called expansion lumen) 61 for circulating the fluid L for expanding the balloon 13, and the lead wires ( Lead insertion lumens 62 are formed for inserting

conductors

50 and 51, respectively. Incidentally, the lead wire 50 is a lead wire individually electrically connected to each temperature sensor 40 to be described later, and the lead wire 51 is a lead wire individually electrically connected to each electrode 111 to be described later. is. These

lead wires

50 and 51 are each made of a conductive material such as SUS (stainless steel). Note that the lead wires 50 are omitted in FIGS. 4 and 5A to 5C.

The fluid L circulating in the circulation lumen 61 is supplied from the fluid injection tube 14 described above to the circulation lumen 61 via the inside of the handle 12 (see FIG. 1). Further, the fluid L flows into the inside of the balloon 13 (first chamber 131, which will be described later) through the side hole 112 that opens to the outer peripheral surface of the tip portion (tip flexible portion 11A) of the catheter shaft 11. (See Fig. 6). In addition, as such a fluid L, physiological saline is mentioned, for example.

Here, the outer diameter of such a catheter shaft 11 is, for example, about 1.0 to 4.0 mm, and the axial length of the catheter shaft 11 is, for example, about 300 to 1500 mm. Materials constituting the catheter shaft 11 include, for example, thermoplastic resins such as polyamide, polyether polyamide, polyurethane, polyether block amide (PEBAX) (registered trademark), and nylon. Among these thermoplastic resins, it is preferable to use PEBAX.

Further, as shown in FIGS. 1 to 4, a plurality of ring-shaped electrodes 111 (three electrodes 111 in this example) made of metal rings are provided near the distal end of the catheter shaft 11 (flexible distal end portion 11A). , and one distal tip 110 are arranged at predetermined intervals. Specifically, each of the plurality of electrodes 111 is fixedly arranged in the middle portion (near the central region) of the distal flexible portion 11A, while the distal tip 110 is fixedly arranged on the distal end side of the distal flexible portion 11A. ing.

Each of these electrodes 111 is made of a metal material with good electrical conductivity, such as aluminum (Al), copper (Cu), SUS (stainless steel), gold (Au), and platinum (Pt). there is Further, the tip 110 is made of, for example, the same metal material as the electrodes 111, and is also made of a resin material such as silicone rubber resin or polyurethane. The outer diameters of the electrode 111 and the distal tip 110 are not particularly limited, but are preferably approximately the same as the outer diameter of the catheter shaft 11 described above.

(Handle 12)
The handle 12 is a portion that is gripped (grasped) by an operator (physician) when using the catheter 1 . The handle 12 is mounted on the proximal end side of the catheter shaft 11 as shown in FIG. 1, and has a flat shape, although the details will be described later. Further, a connector (not shown) having a plurality of terminals is provided inside the handle 12, and base ends of the

lead wires

50 and 51 are individually connected to the respective terminals of this connector. ing. Such a handle 12 is made of synthetic resin such as polycarbonate, acrylonitrile-butadiene-styrene copolymer (ABS).

A detailed configuration example of the handle 12 will be described later (Figs. 9 and 10).

(balloon 13)
As shown in FIGS. 1 to 4, the balloon 13 is provided on the distal end side (flexible tip portion 11A) of the catheter shaft 11, and the fluid L described above (flowing through the flow lumen 61 of the catheter shaft 11) It is configured to be expandable by a fluid L). As shown in FIG. 1, the balloon 13 has a flat shape that forms a plane S13 along the XY plane, and has a flat expandable shape even when expanded by the fluid L. is doing.

As shown in FIGS. 2 to 4, the balloon 13 has a first sheet 130a forming one surface (first surface Sa) and a second sheet 130b forming the other surface (second surface Sb). and The first sheet 130a and the second sheet 130b face each other along the Y-axis direction (see FIG. 3) and are partially fused together. The thickness of each of the first sheet 130a and the second sheet 130b is preferably about 50 to 120 μm, and a preferred example is 80 μm.

As shown in FIGS. 5A to 5C, the first sheet 130a is a flat sheet, and the second sheet 130b has convex portions that are not fused to the first sheet 130a. The protrusions of the first sheet 130a and the second sheet 130b form a storage space for the fluid L when the balloon 13 is inflated. Specifically, as shown in FIGS. 2 and 5A to 5C, the storage space for the fluid L includes a first chamber 131, a second chamber 132 and a third chamber 133, and a communication passage 134 (134a). , 134b) are formed.

The first chamber 131 extends along the axial direction (Z-axis direction) of the catheter shaft 11 . The second chamber 132 extends along the Z-axis direction in parallel with the first chamber 131 while being separated from the first chamber 131 to one side along the X-axis direction. The third chamber 133 extends along the Z-axis direction in parallel with the first chamber 131 while being separated from the first chamber 131 on the other side along the X-axis direction. The communication path 134a is a space (channel) that allows the first chamber 131 and the second chamber 132 to communicate with each other, and the communication path 134b is a space that allows the first chamber 131 and the third chamber 133 to communicate with each other. As shown in FIGS. 1 and 2, these

communication paths

134a and 134b extending from the first chamber 131 on both sides along the X-axis direction extend along the axial direction (Z-axis direction) of the catheter shaft 11. , are formed at regular intervals.

Here, the length of the balloon 13 in the axial direction (Z-axis direction) (length L13 shown in FIG. 2) is preferably about 30 to 100 mm, and a preferred example is 60 mm. . In addition, the width of the balloon 13 in the X-axis direction (width W13 shown in FIG. 5B) is determined, for example, in consideration of the width of the esophagus, which is in the shape of a flattened elliptical tube (inner diameter (major axis) of this elliptical tube). It's like Specifically, the width W13 is preferably about 10 to 30 mm, and a preferred example is 20 mm. In addition, the thickness of the balloon 13 during expansion (thickness H13 shown in FIG. 5B) is determined in consideration of the inner diameter (minor diameter) of the elliptical tube described above. Specifically, the thickness H13 is preferably about 1 to 5 mm, and a preferred example is 2 mm. In addition, the balloon 13 is flat even when inflated as described above, and the ratio of the thickness H13 to the width W13 of the balloon 13 (H13/W13) is preferably about 0.1 to 0.17. , and a preferred example is 0.1 (H13/W13=2 mm/20 mm).

As the constituent material of such a balloon 13, the same resin as the constituent material of the catheter shaft 11 described above can be used, and among such resins, polyurethane is preferable.

Here, as shown in FIG. 2, the tip portion (tip flexible portion 11A) of the catheter shaft 11 is inserted through the above-described first chamber 131 of the balloon 13 . The distal end flexible portion 11A extends from the distal end of the first chamber 131 (balloon 13) while the liquid tightness of the first chamber 131 is ensured.

In addition, the fluid L (see the dashed arrow shown in FIG. 2) flowing into the first chamber 131 through the side hole 112 (see FIG. 6) opened on the outer peripheral surface of the distal end portion of the catheter shaft 11 flows through the communication passage 134 ( 134a, 134b) to flow into the second chamber 132 and the third chamber 133, respectively. As a result, all the accommodation spaces (the first chamber 131, the second chamber 132, the third chamber 133, and the communication passage 134) in the balloon 13 are filled with the fluid L, and the balloon 13 is inflated.

In addition, as shown in FIG. 2, in the balloon 13, the storage spaces for the fluid L (the first chamber 131, the second chamber 132, the third chamber 133, and the communication passage 134) are formed in a grid pattern. In addition, the fused portions of the first sheet 130a and the second sheet 130b are planarly arranged on the XY plane. As a result, the balloon 13 has particularly excellent flatness during expansion. Further, in the balloon 13 having such excellent flatness, the flattened shape of the balloon 13 can be reliably matched with the flattened elliptical tubular shape of the esophagus during expansion and after deflation, although the details will be described later. It is possible.

Furthermore, as shown in FIG. 2, in the balloon 13, the communicating passages 134 (communicating

passages

134a, 134b) extending from the first chamber 131 on both sides along the X-axis direction extend in the axial direction of the catheter shaft 11 (Z-axis direction). direction) at regular intervals. As a result, although the details will be described later, it is possible to use the communicating path 134 visually recognized on the X-ray image as a scale indicating the length.

(Temperature sensor 40)
As shown in FIGS. 4 and 8, a plurality of temperature sensors 40 are planarly arranged on the XY plane on one surface side (first surface Sa side) of the balloon 13 . Each of these temperature sensors 40 is configured using a thermistor, for example, and is embedded in the first sheet 130a that forms the first surface Sa of the balloon 13 . Specifically, for example, an insulating flexible substrate (including temperature sensor 40, wiring 52 and conductor portion 41, etc., which are disposed on this flexible substrate) is embedded in the first sheet 30a. It is As a result, each temperature sensor 40 can be arranged on one surface side (first surface Sa side) of the balloon 13, and since the first sheet 130a in which each temperature sensor 40 is embedded is a flat sheet, It is possible to measure the temperature distribution with accuracy.

4 and 8, the temperature sensors 40 embedded in the first sheet 130a are indicated by solid lines for convenience. 5A to 5C omit illustration of the temperature sensor 40 appearing in the cross section of the first sheet 130a.

As shown in FIGS. 4 and 8, a first temperature sensor group 41G, a second temperature sensor group 42G, and a third temperature sensor group 43G are provided on the first surface Sa side of the balloon 13. is provided.

Each of the first temperature sensor group 41G, the second temperature sensor group 42G, and the third temperature sensor group 43G is a plurality of temperature sensors arranged at equal intervals along the length direction (Z-axis direction) of the balloon 13. 40. The first temperature sensor group 41G, the second temperature sensor group 42G, and the third temperature sensor group 43G are arranged at equal intervals along the width direction (X-axis direction) of the balloon 13 .

The distance between the temperature sensors 40 adjacent to each other along the length direction of the balloon 13 is preferably, for example, about 3.5 to 11.7 mm, and a preferred example is 7.0 mm. . Also, the distance between temperature sensor groups adjacent to each other along the width direction of the balloon 13 is preferably, for example, about 3 to 13 mm, and a preferred example is 7.5 mm.

Here, as shown in FIGS. 4 and 8, the positions of the temperature sensors 40 constituting the first temperature sensor group 41G in the length direction (Z-axis direction) of the balloon 13 and the third temperature sensor group 43G The positions in the length direction of the balloon 13 in each of the temperature sensors 40 constituting the are coincident with each other. On the other hand, the position of the balloon 13 in the length direction of each temperature sensor 40 constituting the second temperature sensor group 42G is the same as that of each temperature sensor 40 constituting the first temperature sensor group 41G or the third temperature sensor group 43G. It is shifted to the distal side of the catheter shaft 11 from the position of 13 in the longitudinal direction.

By arranging the plurality of temperature sensors 40 in this way, the length of the esophagus can be detected by the temperature sensors 40 belonging to each of the first temperature sensor group 41G, the second temperature sensor group 42G, and the third temperature sensor group 43G. It is possible to measure the temperature distribution in the direction. Moreover, the temperature distribution in the width direction of the esophagus can be measured by a plurality of temperature sensors 40 belonging to different temperature sensor groups and having the same or close positions in the longitudinal direction of the balloon 13 . there is By simultaneously measuring the temperature distribution in the length direction and the width direction of the esophagus, it is possible to grasp the temperature distribution inside the esophagus two-dimensionally, although the details will be described later.

In addition, along the length direction of the balloon 13, each temperature sensor 40 that constitutes the first temperature sensor group 41G and each temperature sensor that constitutes the second temperature sensor group 42G or the third temperature sensor group 43G are measured as described above. Since the arrangement position is shifted, the temperature distribution in the length direction of the esophagus can be measured with higher accuracy, although the details will be described later.

Here, as shown in FIG. 8, a conductor portion 41 as described below is provided in the vicinity of such a temperature sensor 40 . Specifically, on the side of the first surface Sa of the balloon 13, the area between the plurality of temperature sensors 40 (area where the temperature sensors 40 are not arranged) is provided with a temperature sensor 40 that contributes to temperature measurement by such a temperature sensor 40. , a conductor portion 41 is provided. In the example shown in FIG. 8, each of the plurality of temperature sensors 40 is electrically connected individually to each lead wire 50 via conductor solder 53 arranged nearby. Incidentally, in FIG. 8 (and FIG. 13 to be described later), such lead wires 50 are shown only for some of the temperature sensors 40 for convenience of illustration.

In the example shown in FIG. 8, such a conductor portion 41 includes a plurality of leg portions each extending from the vicinity of the temperature sensor 40 toward the distance from the first surface Sa side of the balloon 13 . Moreover, the conductor portion 41 including such a plurality of leg portions is individually arranged corresponding to each of the plurality of temperature sensors 40 as shown in FIG. Then, as shown in FIG. 8, such a plurality of legs are arranged (symmetrically arranged) approximately isotropically (preferably isotropically) around the temperature sensor 40 . Specifically, in the example shown in FIG. 8, the plurality of leg portions of the conductor portion 41 extend radially (linearly) with the temperature sensor 40 as the center. Specifically, each leg portion of the conductor portion 41 has a rectangular shape having a long axis along the extending direction. In the example shown in FIG. 8, the direction in which the plurality of temperature sensors 40 are arranged (the Z-axis direction) and the two legs of each conductor portion 41 (the same direction along the X-axis direction with the temperature sensor 40 as a reference) The extending directions of the two legs arranged in the same direction are arranged so as to form an angle (approximately 60°) of the same degree with each other. In particular, for each temperature sensor 40 belonging to the second temperature sensor group 42G, the four leg portions of each conductor portion 41 arranged around and the direction in which the plurality of temperature sensors 40 are arranged (Z-axis direction) are arranged at the same angle (approximately 60°) to each other. Due to such a configuration of the shape and arrangement of the conductor portion 41, although details will be described later, the measurement accuracy of each temperature sensor 40 when measuring the temperature is further improved.

In the example shown in FIG. 8, the plurality of conductor portions 41 are arranged so as to be connected (physically and electrically connected) to the corresponding temperature sensors 40, respectively. As a result, compared to the case where each conductor portion 41 is not connected (physically and electrically connected) to the corresponding temperature sensor 40, for example, as in a modification (see FIG. 13) to be described later, the following is achieved. become. In other words, although the details will be described later, the heat conducted via the conductor portion 41 is more effectively transferred to the temperature sensor 40, so it can be said to be more preferable.

Such a conductor portion 41 has high thermal conductivity compared to other regions between the plurality of temperature sensors 40 (for example, other regions on the insulating flexible substrate as described above). It is desirable to have sex. Examples of materials having such high thermal conductivity (materials with good thermal conductivity) include metal materials such as copper (Cu), gold (Au), silver (Ag), and alloy materials thereof. is mentioned.

By the way, in the example shown in FIG. 8, a predetermined wiring 52 is arranged around such a conductor portion 41 so as to be drawn around. Specifically, around each temperature sensor 40 belonging to the first temperature sensor group 41G and the third temperature sensor group 43G, as shown in FIG. 8, along the axial direction (Z-axis direction) of the balloon 13 , the wiring 52 is routed. On the other hand, around each temperature sensor 40 belonging to the second temperature sensor group 42G, as shown in FIG. Such wiring 52 is made of, for example, the same material as that of the conductor portion 41 described above (such as a metal material or an alloy material having good thermal conductivity).

[B. Detailed configuration of handle 12]
Here, with reference to FIGS. 9 and 10 in addition to FIG. 1, a detailed configuration example of the handle 12 described above will be described. 9 is a side view (YZ side view) showing an example of the detailed configuration of the handle 12, and FIG. 10 is a front view (ZX front view) showing an example of the detailed configuration of the handle 12. It is represented.

First, as shown in FIGS. 1 and 10, in the catheter 1 of the present embodiment, the direction of the plane S12 formed by the flattened handle 12 (parallel to the ZX plane) is the same as that of the flattened balloon 13. The orientation of the plane S13 formed by (parallel to the ZX plane) substantially matches. Specifically, in this example, the plane S12 and the plane S13 are parallel to each other (S12//S13), and the directions of these planes S12 and S13 match each other.

In the handle 12 of the present embodiment, the surface side corresponding to one of the first surface Sa and the second surface Sb of the balloon 13 (in this example, the second surface Sb side) and the other surface side corresponding to the first surface Sa and the second surface Sb. The rear surface side (the first surface Sa side in this example) is configured to be distinguishable.

Specifically, for example, as shown in FIG. 9, the back side of the handle 12 includes a flat surface Sf along the horizontal direction (see the area enclosed by the dashed line shown in FIG. 9), and the handle The surface side of 12 is a non-flat surface Sr. In the example of FIG. 9, only a portion of the back side of the handle 12 is the flat surface Sf. good too.

Further, as shown in FIG. 10, in the handle 12 of the present embodiment, when a plane S12 formed by the flattened handle 12 is planarly viewed on the ZX plane, the axial direction of the catheter shaft 11 is The handle 12 has a left-right asymmetrical shape with respect to (the Z-axis direction). Specifically, in the example of FIG. 10, the shape of the handle 12 is aligned in the width direction (the X-axis direction).

[C. Operation and action/effect]
Next, the operation, actions and effects of the catheter 1 of the present embodiment will be described in detail in comparison with comparative examples (comparative examples 1 and 2).

(C-1. Operation example)
By using this catheter 1, it is possible to measure the internal temperature of the esophagus of a patient during the aforementioned left atrial ablation surgery as follows.

First, the catheter 1 is inserted into the patient's esophagus using a transnasal approach, and the balloon 13 attached to the tip side of the catheter shaft 11 is left in place at a site whose temperature is to be monitored. At the time of insertion, the balloon 13 is wound (wrapped) around the distal end portion of the catheter shaft 11 .

Next, the fluid L (physiological saline) is supplied from the fluid injection tube 14 into the circulation lumen 61 of the catheter shaft 11 . The fluid L supplied into the circulation lumen 61 in this manner flows into the first chamber 131 of the balloon 13 through the side hole 112 opening on the outer peripheral surface of the distal end portion (flexible distal end portion 11A) of the catheter shaft 11 . , through the communication passage 134 (

communication passages

134 a and 134 b ), and also flows into the second chamber 132 and the third chamber 133 . In this manner, the first chamber 131, the second chamber 132, the third chamber 133, and the communication passage 134 accommodate the fluid L, so that the wrapped balloon 13 expands into a flat shape. After such expansion, the balloon 13 is placed so that its width direction (X-axis direction) coincides with the width direction of the esophagus, and one side of the balloon 13 abuts or faces the inner wall of the esophagus on the left atrium side. be done.

Here, when the esophagus is dilated by the inflated balloon 13, or when the inner wall of the esophagus is pressed in the direction of the left atrium by one surface of the inflated balloon 13, the accommodation space for the fluid L ( A part or all of the fluid L contained in the first chamber 131, the second chamber 132, the third chamber 133, and the communication passage 134) is discharged, and the balloon 13 is deflated. As a result, the above-described state (state in which the esophagus is dilated or the inner wall of the esophagus is pressed toward the left atrium) can be eliminated.

Next, the temperature inside the esophagus is simultaneously measured by the temperature sensor 40 arranged on one surface side (first surface Sa side) of the balloon 13, and the temperature distribution inside the esophagus is planarly grasped. Then, when the temperature inside the esophagus measured by any of the temperature sensors 40 reaches a predetermined temperature (for example, 43° C.), for example, power to the ablation catheter is cut off to stop ablation.

(C-2. Comparative Examples 1 and 2)
Here, FIG. 11 schematically shows a state in which the tip portion of the catheter shaft 101A of the temperature measurement catheter (catheter 101) according to Comparative Example 1 is left in the esophagus E. As shown in FIG. FIG. 12 schematically shows a state in which the tip portion of the catheter shaft 201A of the temperature measurement catheter (catheter 201) according to Comparative Example 2 is left in the esophagus E. As shown in FIG.

First, in the catheter 101 of Comparative Example 1 shown in FIG. 11, a plurality of ring-shaped electrodes 102 (electrodes for temperature measurement) are attached to the distal end of the catheter shaft 101A while being spaced apart from each other. A plurality of temperature sensors using thermocouples or the like are electrically connected to each electrode 102 .

By the way, the esophagus E is usually a flat elliptical tube, and the internal temperature of the esophagus E during left atrial ablation is distributed not only in the length direction of the esophagus E but also in the width direction.

However, when the catheter 101 of Comparative Example 1 is indwelled inside the esophagus E, the plurality of electrodes 102 are arranged along the length direction of the esophagus E. Therefore, the temperature distribution in the width direction of the esophagus E cannot be measured. Specifically, for example, as shown in FIG. 11, in this comparative example 1, the distal end portion of the catheter shaft 101A to which the electrode 102 is attached extends from the portion 9 where the temperature is elevated due to cauterization to the width of the esophagus E. If they are placed apart in the direction, the increase in internal temperature of the esophagus E due to cauterization cannot be detected accurately.

On the other hand, in the catheter 201 of Comparative Example 2 shown in FIG. 12, the configuration of the distal end portion of the catheter shaft 201A is as follows. That is, the distal end portion of the catheter shaft 201A is provided with a distal end portion that can be deformed into a meandering shape, that is, a shape that meanders on the same plane as a temperature probe for monitoring the temperature of the surface of a tissue or organ in the body. A deformable section in which is stored is provided.

However, even when the catheter 201 of Comparative Example 2 is placed inside the esophagus E, the temperature distribution in the width direction of the esophagus E cannot be measured with high accuracy. Specifically, when the tip portion of the meandering catheter shaft 201A is placed inside the esophagus E, for example, as shown in FIG. Although they are arranged (scattered in a substantially two-dimensional array), they are as follows. In other words, the temperature sensors are arranged at wider intervals, and adjacent temperature sensors are spaced apart not only in the width direction of the esophagus E, but also in the length direction of the esophagus E. Therefore, it may not be possible to position the electrode 102 attached to the distal end portion of the catheter shaft 201A close to the site 9 whose temperature is elevated due to cauterization. It becomes impossible to detect temperature rise accurately.

Further, in the catheter 201 of Comparative Example 2, when the distal end portion of the catheter shaft 201A placed inside the esophagus E is deformed (restored) into a meandering shape, the distal end portion dilates the esophagus E, causing the left atrium. As a result of increasing the contact area with the rear wall, there is also the following possibility. That is, the risk of overheating the esophagus E increases, which may lead to an increase in complications.

Furthermore, in the

catheters

101 and 201 of Comparative Examples 1 and 2, the temperature sensor is spot-welded to the inner peripheral surface of each electrode 102, and the inner peripheral surface temperature of each electrode 102 is regarded as the internal temperature of the esophagus E. Measured with a temperature sensor. However, since it takes a certain amount of time for the inner peripheral surface of each electrode 102 to rise in temperature, there are cases where the change in the actual internal temperature of the esophagus E cannot be detected quickly.

In particular, since there is a temperature difference between the electrode portion facing the ablation side and the electrode portion on the side opposite to the ablation side, a temperature sensor is mounted on the inner peripheral surface of the electrode portion on the side opposite to the ablation side. is located, there are the following risks. That is, even if the internal temperature of the esophagus E measured by this temperature sensor does not reach the temperature at which the current should be cut off, the electrode portion facing the cautery side reaches the temperature at which the esophagus E should be cut off. may be in an overheated state, and in such a case, the esophagus E may be damaged.

(C-3. Present embodiment)
On the other hand, in the catheter 1 of the present embodiment, the balloon 13, the handle 12, and the like each have the above-described configuration, so that the following functions and effects can be obtained.

(Action and effect of balloon 13)
First, in the catheter 1 of the present embodiment, unlike Comparative Examples 1 and 2, the internal temperature of a hollow organ such as the esophagus is measured as follows. That is, in the catheter 1, a plurality of temperature sensors are arranged planarly on the first surface Sa side of the balloon 13 in a flattened state (inflation) inside the esophagus or the like. 40 measures the internal temperature, such as the esophagus. Thus, unlike Comparative Examples 1 and 2, the internal temperature of the esophagus or the like can be grasped two-dimensionally, and the temperature of the site to be monitored can be measured more reliably.

Specifically, in the present embodiment, during the left atrial ablation operation, the temperature is measured by the temperature sensor 40 arranged planarly on the one surface side (first surface Sa side) of the balloon 13, so that a flat elliptical shape is obtained. It is possible to planarly grasp the distribution of the internal temperature of the tubular esophagus or the like. As a result, one or more temperature sensors 40 can reliably measure the temperature of the site whose temperature is elevated by cauterization (the site whose temperature should be monitored).

Further, in the present embodiment, since the balloon 13 is flat even when inflated, the inner wall of the esophagus or the like is pressed in the direction of the left atrium by one surface of the inflated balloon 13 during the left atrial ablation operation. can be prevented. Furthermore, by deflating the balloon 13 during left atrial ablation, it is possible to more reliably avoid pressing the inner wall of the esophagus or the like in the direction of the left atrium by one surface of the balloon 13. be able to. In addition, by deflating (deflating) the balloon 13 during left atrial ablation, it is possible to more reliably avoid the expansion of the esophagus or the like in the width direction by the balloon 13 .

In addition, in the present embodiment, the accommodation space (the first chamber 131, the second chamber 132, the third chamber 133, and the communication passage 134) for the fluid L in the balloon 13 is formed in a grid pattern, and the first sheet 130a and the The fused portions with the second sheet 130b are arranged in a plane. Accordingly, in this embodiment, the flatness of the balloon 13 during expansion is particularly excellent.

Furthermore, in the present embodiment, the communication passages 134 (

communication passages

134a, 134b) extending from the first chamber 131 on both sides along the X-axis direction extend along the axial direction (Z-axis direction) of the catheter shaft 11, etc. formed at intervals. Thereby, the communicating path 134 visually recognized on the X-ray image can be used as a scale indicating the length.

In addition, in the present embodiment, between the temperature sensor 40, which is embedded in the first sheet 130a and arranged on one surface side (first surface Sa side) of the balloon 13, and the portion whose temperature is to be measured. , there is no ring-shaped electrode 102 (electrode for temperature measurement) as in Comparative Examples 1 and 2 described above. As a result, changes in the internal temperature of the esophagus or the like can be measured more quickly than in Comparative Examples 1 and 2 in which temperature measurement is performed using such electrodes 102 .

(Action and effect of the conductor portion 41)
Further, in the balloon 13 (flat balloon 13) of the present embodiment, the conductor portion 41 (see FIG. 8) having the configuration described above is provided, so that the following functions and effects can be obtained, for example. .

That is, first, in the balloon 13 of the present embodiment, conductor portions 41 are provided in regions between the plurality of temperature sensors 40 on the side of the first surface Sa, and contribute to temperature measurement by such temperature sensors 40. ing. As a result, the heat in the area between the temperature sensors 40 (the area where the temperature sensors 40 are not arranged) is effectively transmitted to the temperature sensors 40 via the conductor portion 41, so that more accurate heating can be achieved. Temperature measurement (measurement of temperature distribution) is performed. In this embodiment, it is possible to improve the accuracy of temperature measurement by the temperature sensor 40 . In addition, since heat is efficiently transmitted to the temperature sensor 40, it is possible to shorten the measurement time during temperature measurement.

Further, in the present embodiment, such a conductor portion 41 includes a plurality of leg portions each extending from the vicinity of the temperature sensor 40 toward the distance from the first surface Sa side of the balloon 13. , so it looks like this: That is, the heat in the distant area of the temperature sensor 40 is easily transmitted to the vicinity of the temperature sensor 40 through such a plurality of legs. can be further improved.

Furthermore, in the present embodiment, such a plurality of legs are arranged substantially isotropically around the temperature sensor 40, so the following is obtained. That is, the heat around the temperature sensor 40 is transmitted to the temperature sensor 40 via a plurality of legs arranged substantially isotropically. It is possible to further improve the measurement accuracy during measurement.

In addition, in the present embodiment, the conductor portion 41 including such a plurality of legs is individually arranged corresponding to each of the plurality of temperature sensors 40, so the following is obtained. . That is, in each of the plurality of temperature sensors 40, heat is effectively transmitted through the conductor portion 41 including the plurality of legs, so that the temperature distribution of the plurality of temperature sensors 40 as a whole can be measured more accurately. will be done. As a result, in this embodiment, it is possible to further improve the measurement accuracy when measuring the temperature.

In addition, in the present embodiment, when such a conductor portion 41 has high thermal conductivity compared to other regions between the plurality of temperature sensors 40, the following become that way. That is, since heat is more easily transmitted to the temperature sensor 40 via the conductor portion 41 having such high thermal conductivity, the temperature distribution can be measured with higher accuracy. Further improvement is possible.

(Action and effect of handle 12, etc.)
Further, in the catheter 1 of the present embodiment, the orientation of the plane S12 formed by the flattened handle 12 substantially matches the orientation of the plane S13 formed by the flattened balloon 13 . As a result, even when the flat balloon 13 is inserted into a hollow organ such as the esophagus, the orientation of the plane S13 formed by the balloon 13 uses the orientation of the plane S12 formed by the flat handle 12. so that it can be easily comprehended. Therefore, in the present embodiment, as compared with Comparative Examples 1 and 2, convenience when using the catheter 1 (for example, when measuring the internal temperature of the esophagus or the like during a left atrial ablation operation on a patient) is improved. becomes possible.

In the present embodiment, the handle 12 is configured so that the front side corresponding to one of the first surface Sa and the second surface Sb of the balloon 13 and the back side corresponding to the other can be distinguished. there is As a result, the temperature measurement surface of the balloon 13 (the planar arrangement surface of the plurality of temperature sensors 40 on the first surface Sa side) of the balloon 13 can be easily grasped from the surface side and the rear surface side of the handle 12 . As a result, in this embodiment, it is possible to further improve the convenience of using the catheter 1 .

Specifically, in the present embodiment, the back side of the handle 12 includes the flat surface Sf and the front side of the handle 12 is the non-flat surface Sr, as follows. That is, the temperature measurement surface of the balloon 13 can be intuitively grasped while making it easier to stably place the handle 12 on, for example, a workbench (on a horizontal plane). As a result, in this embodiment, it is possible to further improve the convenience of using the catheter 1 .

In addition, in the present embodiment, the handle 12 has a laterally asymmetrical shape with respect to the axial direction of the catheter shaft 11 when the plane S12 formed by the flattened handle 12 is viewed from above. As a result, the temperature measurement surface of the balloon 13 can be intuitively grasped, and the handle 12 can be set to a shape that is easy to hold according to, for example, the dominant hand (right-handed or left-handed) of the user of the catheter 1. Become. As a result, in this embodiment, it is possible to further improve the convenience of using the catheter 1 .

<2. Variation>
Next, a modification of the above embodiment will be described. In the following description, the same reference numerals are given to the same components as those in the embodiment, and the description thereof will be omitted as appropriate.

FIG. 13 is a rear view (ZX rear view) showing a detailed configuration example of the balloon 13A in the catheter (catheter 1A) according to the modification. The catheter 1A of this modified example corresponds to the catheter 1 of the embodiment in which a balloon 13A described below is provided instead of the balloon 13, and other configurations are the same.

The balloon 13A of this modified example corresponds to the balloon 13 of the embodiment in which a conductor portion 41A is provided instead of the conductor portion 41 described above, and other configurations are the same. The conductor portion 41A of this modified example has basically the same configuration as the conductor portion 41 (see FIG. 8) of the embodiment, but the shape of the conductor portion 41A is slightly different from the shape of the conductor portion 41. ing.

Specifically, as described above, the plurality of leg portions in the conductor portion 41 shown in FIG. 2 extends in an L shape with the temperature sensor 40 as the center. Specifically, a pair of leg portions facing each other along the axial direction (Z-axis direction) of the balloon 13 are line-symmetrical ( are arranged so as to form L-shapes facing in opposite directions to each other.

Even in such a modified example of the configuration, it is possible to obtain the same effect by basically the same action as in the embodiment.

<3. Other modified examples>
Although the present invention has been described above with reference to the embodiments and modifications, the present invention is not limited to these embodiments and the like, and various modifications are possible.

For example, the shape, arrangement position, size, number, material, etc. of each member described in the above embodiments and the like are not limited, and other shapes, arrangement positions, sizes, numbers, materials, etc. may be used.

Specifically, for example, in the above embodiment and the like, the tip portion of the catheter shaft inserted into the first chamber of the balloon is housed in the first chamber without extending from the tip of the first chamber. good too. Further, in the above-described embodiments and the like, there may be only one communication passage connecting the first chamber and the second chamber, and one communication passage connecting the first chamber and the third chamber. Further, the positions of the temperature sensors that make up the first temperature sensor group in the length direction of the balloon, the positions of the temperature sensors that make up the second temperature sensor group in the length direction of the balloon, and the third temperature sensor group are arranged. The lengthwise position of the balloon for the constituent temperature sensors may coincide with each other.

In addition, in the above-described embodiment and the like, the accommodation space for the fluid L (the first chamber 131, the second chamber 132, the third chamber 133, and the communication passage 134) in the balloon is formed in a grid pattern, and the first sheet 130a and the second sheet 130a Although the fused portions with the sheet 130b are arranged in a plane, it is not limited to this example. Furthermore, in the above embodiment and the like, the communicating passages 134 (communicating

passages

134a and 134b) extending from the first chamber 131 to both sides along the X-axis direction are formed at regular intervals along the axial direction of the catheter shaft 11. but not limited to this example.

In the above-described embodiment and the like, the handle 12 is configured so that the front side corresponding to one of the first surface Sa and the second surface Sb of the balloon and the back side corresponding to the other can be distinguished. However, examples of the distinguishable configuration are not limited to those described in the above embodiments and the like. In addition, the correspondence relationship between the first surface Sa and the second surface Sb of the balloon and the front surface side and the rear surface side of the handle 12 may be reversed from, for example, the above embodiment. That is, considering the mode of use of the catheter 1, for example, the front surface side of the handle 12 corresponds to the first surface Sa side of the balloon, and the back surface side of the handle 12 corresponds to the second surface Sb side of the balloon. You may do so. Furthermore, the front side and the back side of such a handle 12 may not be distinguishable, for example.

In addition, in the above embodiment and the like, the handle 12 is a flat handle, and the orientation of the plane formed by the flat handle 12 is substantially the same as the orientation of the plane formed by the flat balloon. Although the case of matching is described as an example, it is not limited to this example. That is, for example, the orientations of such planes may not match each other, and further, for example, the shape of the handle 12 may be a shape other than a flat shape (non-flat shape, three-dimensional shape). may be

Furthermore, in the above-described embodiment and the like, the configuration (shape, arrangement position, size, number, material, etc.) of the temperature sensor 40, the

conductor portions

41 and 41A, the wiring 52, etc. has been specifically described. Arrangement position, size, number (one or more), material, and the like may be used. Specifically, for example, in the above embodiment and the like, an example in which a plurality of

conductor portions

41 and 41A are provided has been described, but the present invention is not limited to this example. , 41A may be provided only once. Further, in the above embodiment and the like, the case where the temperature sensor 40 is configured using a thermistor has been described as an example. It may be configured using other elements such as.

Also, for example, the shape of the catheter shaft 11 near the tip (tip flexible portion 11A) may change in both directions or in one direction according to a predetermined operation on the handle 12 . In other words, the deflection operation may be enabled in the vicinity of the tip of the catheter shaft 11 .

Furthermore, in the above embodiments and the like, a case where the hollow organ in the patient's body is the esophagus will be described as an example. Although the description has been made by taking a catheter as an example, it is not limited to this example. That is, the present invention can also be applied to catheters used for measuring the internal temperature of other hollow organs in the body.

Claims

A catheter for measuring the internal temperature of a hollow organ within the body, comprising:
a catheter shaft extending axially and having a fluid flow lumen;
a handle attached to the proximal end of the catheter shaft;
a flattened balloon provided on the distal end side of the catheter shaft, configured to be expandable by the fluid, and having a first surface and a second surface facing each other;
a plurality of temperature sensors arranged in a plane on the first surface side of the balloon,
The balloon is configured to be expandable in a flat shape even during the expansion,
On the first side of the balloon, in the area between the temperature sensors, one or more conductors are provided that contribute to temperature measurement at the temperature sensors. Catheter.
2. The catheter of claim 1, wherein the conductor portion includes a plurality of legs each extending away from near the temperature sensor on the first surface side of the balloon.
3. The catheter of claim 2, wherein the plurality of legs are substantially isotropically arranged around the temperature sensor.
4. The catheter according to claim 2 or 3, wherein the conductor section including the plurality of leg sections is individually arranged corresponding to each of the plurality of temperature sensors.
5. The catheter according to any one of claims 1 to 4, wherein the conductor portion has high thermal conductivity compared to other regions between the plurality of temperature sensors. .
The handle is a flat handle, and
The catheter according to any one of claims 1 to 5, wherein the orientation of the plane formed by the flattened handle substantially matches the orientation of the plane formed by the flattened balloon.
the hollow organ in the body is the esophagus;
The catheter according to any one of claims 1 to 6, which is used for measuring the internal temperature of the esophagus during left atrial ablation on a patient.