JP2025129061A - Intracardiac defibrillation catheter - Google Patents

Abstract

To provide an intracardiac defibrillation catheter which has excellent operability in an inferior vena cava approach and makes it easy for a manipulator to place a defibrillation electrode at a desired position.SOLUTION: The intracardiac defibrillation catheter comprises: a catheter shaft with an electrode placed on its surface; and an operating part connected to a proximal end side of the catheter shaft. The catheter shaft has: a tube structure area which is placed in a longitudinally first section of the catheter shaft and has a lumen structure constituted of a plurality of tubes separated from each other; a multi-lumen structure area which is placed in a second section being on a longitudinally distal end side of the first section of the catheter shaft and has a lumen structure having a plurality lumens formed in a single core; a lead wire group which extends continuously over both a lumen in the tube structure area and a lumen in the multi-lumen structure area and whose one end is connected to the electrode; and a rope-like member which extends continuously over both the lumen in the tube structure area and the lumen in the multi-lumen structure area and whose one end is connected to the operating part.SELECTED DRAWING: Figure 26

Description

This disclosure relates to an intracardiac defibrillation catheter.

Traditionally, intracardiac defibrillation catheters have been widely used as medical devices for treating atrial fibrillation, atrial tachycardia, and other conditions.

Intracardiac defibrillation catheters have multiple wide defibrillation electrodes positioned on the right atrium (RA) or left atrium (CS) for the purpose of treating atrial fibrillation, atrial tachycardia, and other conditions. When performing treatments such as intracardiac defibrillation, electrical energy is supplied using the multiple defibrillation electrodes on the right atrium (RA) or left atrium (CS). Furthermore, the multiple electrodes are used to measure intracardiac electrical potentials within the heart, regardless of whether a tachycardia attack is present or not.

This type of intracardiac defibrillation catheter is described, for example, in Patent Documents 1 and 2.

JP 2010-63708 A Japanese Patent Application Laid-Open No. 2019-150526

To perform intracardiac defibrillation via the inferior vena cava approach, an intracardiac defibrillation catheter with multiple defibrillation electrodes must be placed in the appropriate position. Therefore, the intracardiac defibrillation catheter must be highly maneuverable, allowing the technician to place the defibrillation electrodes in the desired position. However, conventional intracardiac defibrillation catheters are time-consuming and still lack maneuverability.

This disclosure was made in consideration of the above points and provides an intracardiac defibrillation catheter that is easy to operate and allows the operator to easily place defibrillation electrodes at the desired position.

One aspect of the intracardiac defibrillation catheter of the present disclosure comprises:
An intracardiac defibrillation catheter having a catheter shaft with electrodes arranged on its surface and an operation unit connected to a proximal end side of the catheter shaft,
The catheter shaft
a tube structure region disposed in a first section in the longitudinal direction of the catheter shaft and having a tubular structure formed by a plurality of tubes separate from one another;
a multi-lumen structure region disposed in a second section of the catheter shaft that is located on the distal end side of the first section in the longitudinal direction, the multi-lumen structure region having a tubular structure in which multiple lumens are formed in one core;
a group of lead wires extending continuously through both the lumen of the tube structure region and the lumen of the multi-lumen structure region, one end of which is connected to the electrode;
a cord-like member that extends continuously across both the lumen of the tube structure region and the lumen of the multi-lumen structure region, and one end of which is connected to the operation unit;
Equipped with.

The present invention makes it possible to realize an intracardiac defibrillation catheter that is easy to operate and allows the operator to easily place the defibrillation electrodes at the desired position.

FIG. 1 is a diagram illustrating placement of a catheter in a cardiac cavity in the first embodiment. FIG. 1 is an external view showing the overall configuration of an intracardiac defibrillation catheter on the right atrium side (for RA) in the first embodiment. FIG. 1 is an external view showing the overall configuration of an intracardiac defibrillation catheter on the left atrium side (for CS) in the first embodiment. Cross-sectional view of a tube structure region in configuration example 1 Cross-sectional view of a multi-lumen structure region in configuration example 1 Cross-sectional view of a multi-lumen structure region in configuration example 1 4 and 5A (or FIG. 5B) is a cross-sectional view of the catheter shaft in the first configuration example taken along a plane including E-E. Cross-sectional view of a tube structure region in configuration example 2 Cross-sectional view of a multi-lumen structure region in configuration example 2 9 is a cross-sectional view of the catheter shaft in Configuration Example 2 taken along a line including E-E in FIGS. 7 and 8. Cross-sectional view of a multi-lumen structure region in configuration example 3 Cross-sectional view of a tube structure region in Configuration Example 4 Cross-sectional view of a multi-lumen structure region in configuration example 4 13 is a cross-sectional view of the catheter shaft in Configuration Example 4 taken along a line including E-E in FIGS. 11 and 12. Cross-sectional view of a tube structure region in configuration example 5 Cross-sectional view of a multi-lumen structure region in configuration example 5 16 is a cross-sectional view of the catheter shaft in Configuration Example 5 taken along a line including E-E in FIGS. 14 and 15. Cross-sectional view of a tube structure region in Configuration Example 6 Cross-sectional view of a multi-lumen structure region in configuration example 6 17 and 18. A cross-sectional view of the catheter shaft in Configuration Example 6 taken along the line E-E in FIGS. Cross-sectional view of a tube structure region in Configuration Example 7 Cross-sectional view of a multi-lumen structure region in configuration example 7 20 and 21. A cross-sectional view of the catheter shaft in Configuration Example 7 taken along the line E-E in FIGS. FIG. 10 shows an example in which a reinforcing body is provided. FIG. 10 shows an example in which a reinforcing body is provided. FIG. 10 is a diagram illustrating placement of a catheter in a cardiac cavity in the second embodiment. FIG. 10 is an external view showing the overall configuration of an intracardiac defibrillation catheter according to a second embodiment. Cross-sectional view of a tube structure region in configuration example 1 Cross-sectional view of a tube structure region in configuration example 1 Cross-sectional view of a multi-lumen structure region in configuration example 1 27, 28, and 29 are cross-sectional views of the catheter shaft in Configuration Example 1 taken along a plane including L-L in FIGS. Cross-sectional view of a tube structure region in configuration example 2 Cross-sectional view of a tube structure region in configuration example 2 Cross-sectional view of a multi-lumen structure region in configuration example 2 34 is a cross-sectional view of the catheter shaft in Configuration Example 2 taken along a plane including LL in FIGS. 31, 32, and 33. 10 is a cross-sectional view of a multi-lumen structure region in configuration example 1 of embodiment 3. 10 is a cross-sectional view of a tube structure region in configuration example 1 of embodiment 3. 35 and 36. A cross-sectional view of a catheter shaft in Configuration Example 1 of Embodiment 3 taken along a line including E-E in FIGS. 10 is a cross-sectional view of a multi-lumen structure region in configuration example 2 of embodiment 3. 10 is a cross-sectional view of a multi-lumen structure region in configuration example 2 of embodiment 3. 10 is a cross-sectional view of a tube structure region in configuration example 2 of embodiment 3. 38-40 , a cross-sectional view of a catheter shaft in Configuration Example 2 of Embodiment 3, taken along a line including E-E. FIG. 10 is a diagram illustrating the cross-sectional position of the third embodiment. 10 is a cross-sectional view of a multi-lumen structure region in configuration example 3 of embodiment 3. 10 is a cross-sectional view of a multi-lumen structure region in configuration example 3 of embodiment 3. 10 is a cross-sectional view of a tube structure region in configuration example 3 of embodiment 3. 43 to 45. A cross-sectional view of a catheter shaft in Configuration Example 3 of Embodiment 3 taken along a line including E-E in FIGS.

Embodiments of the present disclosure will be described in detail below with reference to the drawings.

<1> First embodiment
In this embodiment, as shown in FIG. 1, a configuration of an intracardiac defibrillation catheter will be described when intracardiac defibrillation is performed using two intracardiac defibrillation catheters 1 and 2.

Intracardiac defibrillation catheter 1 is a right atrial (RA) electrode catheter, and intracardiac defibrillation catheter 2 is a left atrial, coronary sinus (CS) electrode catheter.

Intracardiac defibrillation catheter 1 is inserted into the right atrium 3 via the patient's inferior vena cava and left in place at a predetermined position on the inner wall of the right atrium 3. Intracardiac defibrillation catheter 2 is inserted into the coronary sinus 4 in the right atrium via the patient's inferior vena cava and left in place.

Figure 2 is an external view showing the overall configuration of intracardiac defibrillation catheter 1 in the right atrium (RA), and Figure 3 is an external view showing the overall configuration of intracardiac defibrillation catheter 2 in the coronary sinus (CS). Intracardiac defibrillation catheter 1 and intracardiac defibrillation catheter 2 have the same basic configuration, with the only difference being the placement of the electrodes.

Each of the intracardiac defibrillation catheters 1 and 2 has a catheter shaft 100, a handle portion 200, and connectors 301 and 302.

The catheter shaft 100 of the intracardiac defibrillation catheter 1 in the right atrium (RA) is provided with an RA electrode group 110 and an inspection electrode group 130. The RA electrode group 110 consists of multiple (eight in this embodiment) wide ring-shaped electrodes 111 arranged at a predetermined distance, and the inspection electrode group 130 consists of multiple ring-shaped electrodes arranged at a predetermined distance.

The catheter shaft 100 of the coronary sinus (CS) intracardiac defibrillation catheter 2 is provided with a CS electrode group 120 and a testing electrode group 130. The CS electrode group 120 consists of multiple (eight in this embodiment) wide ring-shaped electrodes 121 arranged at a predetermined distance, and the testing electrode group 130 consists of multiple ring-shaped electrodes arranged at a predetermined distance.

In this embodiment, intracardiac defibrillation is performed using two intracardiac defibrillation catheters 1 and 2. This allows the position of the intracardiac defibrillation catheter 1 on the right atrium (RA) side of the coronary sinus (CS) to be changed independently of the intracardiac defibrillation catheter 2 on the left atrium side, thereby enabling efficient atrial defibrillation.

In other words, the intracardiac defibrillation catheters described in Patent Documents 1 and 2, etc., are inserted into the cardiac chambers via the jugular or subclavian vein, which limits the placement position of the right atrium (RA) electrode, and if the defibrillation threshold is high, there is a risk that atrial fibrillation and atrial tachycardia may not be stopped. Using intracardiac defibrillation catheters 1 and 2, as in the present embodiment, does not present such problems.

<1-1> Configuration example 1 of catheter shaft 100
The catheter shaft 100 has a tube structure region 100a and a multi-lumen structure region 100b. The tube structure region 100a is arranged in a first section in the longitudinal direction of the catheter shaft 100 and has a luminal structure formed by one or more tubes. The multi-lumen structure region 100b is arranged in a second section in the longitudinal direction of the catheter shaft 100 that is different from the first section and has a luminal structure in which multiple lumens are formed.

In an embodiment, the length of the catheter shaft 100 is 1000 to 1200 mm, and the length of the multi-lumen structure region 100b (i.e., the length of the second section) is 100 to 200 mm. The diameter of the catheter shaft 100 is 2 mm.

Figures 4 and 5A (or Figure 5B) are cross sections A-A and B-B in Figure 2, respectively. Figure 6 is a cross section E-E in Figures 4 and 5A (or Figure 5B).

Figure 4 is a cross-sectional view of the tube structure region 100a. As can be seen from Figure 4, the catheter shaft 100 has multiple tubes 101, 102, and 103 in the tube structure region 100a. Tube 101 is a tube that forms the outer shell of the catheter shaft 100, tube 102 is a tube that houses lead wires 140 that are connected to the RA electrode group, CS electrode group, or testing electrode group, and tube 103 is a tube that houses the pull wire 150. An insulating film is formed on the surface of each lead wire 140, and each lead wire 140 is also insulated by this insulating film.

Each of the tubes 101, 102, and 103 is made of a resin with insulating properties. Specifically, each of the tubes 101, 102, and 103 is made of, for example, polyvinyl chloride, polyurethane, polyamide, fluorine-based resin, or polyimide. Of the multiple tubes 101, 102, and 103, the tube 101 that forms the outer shell of the catheter shaft 100 is thicker than the other tubes 102 and 103. This reliably prevents blood from entering the interior of the tube 101.

Figure 5A (or Figure 5B) is a cross-sectional view of the multi-lumen structure region 100b. As can be seen from Figures 5A and 5B, the catheter shaft 100 has multiple lumens 161, 162, and 163 formed in the multi-lumen structure region 100b. The lumens 161, 162, and 163 are formed by drilling a cylindrical core 170 of the catheter shaft 100 in the longitudinal direction of the catheter shaft 100. Note that the core 170 may be covered with a shell 171 as shown in Figure 5B, or may not be covered with a shell 171 as shown in Figure 5A.

In the configurations of Figures 5A and 5B, the core 170 is made of, for example, a low-hardness nylon elastomer. In the configuration of Figure 5B, the outer periphery of the core 170 may be covered by a shell 171 made of a high-hardness nylon elastomer. Furthermore, the core 170 and the lumens 161, 162, and 163 are partitioned by fluororesin layers 161a, 162a, and 163a.

However, the configuration of the multi-lumen structure region 100b is not limited to this. The multi-lumen structure region 100b may have at least a core 170 and multiple lumens drilled in the longitudinal direction of the core 170.

The hollow portions of lumens 162 and 163 are perfectly circular. In contrast, the hollow portion of lumen 161 is not perfectly circular. Specifically, lumen 161 is shaped like an oval coin. Alternatively, lumen 161 may be described as having two opposing straight lines and two opposing curved lines. Furthermore, the hollow portion of lumen 161 may be elliptical or nearly elliptical, oval (racetrack), or some other shape. For example, the cross-sectional shape of lumen 161 may be shaped like glasses or a gourd, thereby creating a depression (waist). By adopting such a shape and positioning lumens 162 and 163 near the depression (waist), the positions of lumens 162 and 163 can be more stabilized. Stabilizing the positions of lumens 162 and 163 leads to improved operation accuracy. Furthermore, the hollow portion of lumen 161 may be a composite combination of different shapes, such as a perfect circle or rectangle. Lumen 161 is formed along the diameter of core 170, and lumens 162 and 163 are formed on either side of lumen 161.

A lead wire 140 is inserted through lumen 161, and a pull wire 150 is inserted through lumen 162. In the example of Figure 5A (or Figure 5B), nothing is inserted through lumen 162. Therefore, lumen 162 does not need to be formed.

The proximal end of the pull wire 150 is connected to the dial 201 of the handle portion 200. The distal end of the pull wire 150 is connected to the distal end or near the distal end of the catheter shaft 100. As can be seen in Figure 5A (or Figure 5B), the pull wire 150 passes through a position eccentric to the center of the catheter shaft 100. As a result, when the user operates the dial 201, the pull wire 150 is pulled by the dial 201, causing the distal end of the catheter shaft 100 to bend, for example, downward (in the -a direction) in Figure 5A (or Figure 5B), thereby allowing the catheter shaft 100 to be advanced in the desired direction within the blood vessel and heart.

The configuration of the catheter shaft 100 of this embodiment will be described in more detail using Figure 6. Figure 6 is a cross-sectional view of the catheter shaft 100 taken along a plane including E-E in Figures 4 and 5A (or 5B).

Respective lead wires 140 are connected to each electrode 111 (121, 131) of the RA electrode group 110 (or the CS electrode group 120, or the testing electrode group 130). Here, each lead wire 140 is connected to each electrode 111 (121, 131) in the multi-lumen structure region 100b. The electrodes 111 (121, 131) and the lead wires 140 are connected by, for example, welding.

As described above, according to the configuration shown in Figures 2 to 6, the catheter shaft 100 has a tube structure region 100a arranged in a first longitudinal section of the catheter shaft 100 and having a luminal structure composed of multiple separate tubes 101, 102, 103, and a luminal structure arranged in a second longitudinal section different from the first section of the catheter shaft 100 and having a luminal structure in which multiple lumens 161, 162, 163 are formed in a single core 170. The device includes a multi-lumen structure region 100b, a group of lead wires (lead wires 140) that extend continuously through both the lumen of the tube structure region 100a and the lumen of the multi-lumen structure region 100b, with one end connected to the electrode 111 (121, 131), and a pull wire 150 that extends continuously through both the lumen of the tube structure region 100a and the lumen of the multi-lumen structure region 100b, with one end connected to the operating section (handle section 200).

<1-2> Configuration example 2 of catheter shaft 100
In the above section <1-1>, a unidirectional type catheter shaft 100 was described, that is, a catheter shaft 100 whose distal end can be bent in only one direction (-a direction) by a single pull wire 150. In this configuration example 2, the configuration of a bidirectional type catheter shaft 100 will be described.

Figures 7-9, in which the same reference numerals are used to denote parts corresponding to those in Figures 4-6, show the configuration of a bidirectional catheter shaft 100. Figure 7 is a cross-sectional view of the tube structure region 100a, Figure 8 is a cross-sectional view of the multi-lumen structure region 100b, and Figure 9 is a cross-sectional view of the catheter shaft 100 taken along a plane including E-E in Figures 7 and 8.

Compared to the configuration of the unidirectional catheter shaft 100, the bidirectional catheter shaft 100 of this configuration example 2 has two pull wires 150, 151. Also, as can be seen in Figure 7, a tube 104 that houses the pull wire 151 is provided in the tube structure region 100a.

The two pull wires 150, 151 are wound around the dial 201 in opposite directions. This allows the tip of the catheter shaft 100 to be selectively bent in one of two directions (-a direction, +a direction) depending on the direction of rotation of the dial 201.

<1-3> Configuration example 3 of catheter shaft 100
The catheter shaft 100 of Configuration Example 3 differs from the catheter shaft 100 of Configuration Example 2 in the configuration of the multi-lumen structure region 100b.

Figure 10, in which parts corresponding to those in Figure 8 are assigned the same reference numerals, is a cross-sectional view of the catheter shaft 100 of Configuration Example 3. Compared to the configuration in Figure 8, the catheter shaft 100 of Configuration Example 3 has a reinforcing plate 180. Of the lumens 161, 162, and 163 in the multi-lumen structure region 100b, the reinforcing plate 180 is located in lumen 161, in which the lead wire 140 is located.

The reinforcing plate 180 is a long, thin plate that extends in the longitudinal direction of the catheter shaft 100 within the lumen 161. The reinforcing plate 180 is harder than the main material (core 170) that makes up the multi-lumen structure region 100b, and is made of an insulating material. In this example, the reinforcing plate 180 is made of resin. Note that the reinforcing plate 180 does not have to be insulating.

The reinforcing plate 180 increases the rigidity of the multi-lumen structure region 100b in a direction perpendicular to the longitudinal direction, suppressing buckling of the multi-lumen structure region 100b. In particular, as can be seen in Figure 10, the reinforcing plate 180 is positioned so that its main surface is perpendicular to the direction (±a direction) in which the catheter tip is deflected by the pull wires 150, 151. This allows the catheter shaft 100 to bend in the deflection direction (±a direction) by the pull wires 150, 151 in the multi-lumen structure region 100b, but is difficult to bend in other directions. This makes it possible to achieve a catheter shaft 100 that bends in the desired direction (±a direction) but is difficult to bend in other directions.

Furthermore, the lumen 161 in which the reinforcing plate 180 is disposed has a shape that includes a flat hollow cross section when the catheter shaft 100 is cut along a plane perpendicular to the longitudinal direction. In the example of Figure 10, the hollow cross section forming the lumen 161 is oval. The width of the reinforcing plate 180 is equal to or slightly shorter than the longitudinal length of this oval shape. At the very least, the width of the reinforcing plate 180 is longer than the shorter width of the oval shape. This prevents the reinforcing plate 180 from rotating about its axis within the lumen 161. As a result, operation in the deflection direction (±a direction) by the pull wires 150, 151 is stable, and bending of the catheter shaft 100 in directions other than the desired direction can be prevented.

The cross-sectional shape of the lumen 161 in which the reinforcing plate 180 is disposed is not limited to the oval shape shown in Figure 10, etc. The cross-sectional shape of the lumen 161 may be, for example, an ellipse, or any other shape. The cross-sectional shape of the lumen 153 in which the reinforcing plate 180 is disposed does not have to be a perfect circle, and may be any shape that can suppress rotation of the reinforcing plate 180 around the axis within the lumen 161.

<1-4> Configuration example 4 of catheter shaft 100
The catheter shaft 100 of Configuration Example 4 differs from the catheter shaft 100 of Configuration Example 1 in the configuration of the multi-lumen structure region 100b.

Figures 11 to 13, in which parts corresponding to those in Figures 4 to 6 are assigned the same reference numerals, are cross-sectional views of the catheter shaft 100 of Configuration Example 4. Figure 11 is a cross-sectional view of the tube structure region 100a, Figure 12 is a cross-sectional view of the multi-lumen structure region 100b, and Figure 13 is a cross-sectional view of the catheter shaft 100 taken along a plane including E-E in Figures 11 and 12.

As can be seen from Figure 12, the multi-lumen structure region 100b of the catheter shaft 100 of configuration example 4 has two lumens 161-1 and 161-2 formed as lumens for accommodating the lead wire 140.

The multiple lead wires 140 housed in the tube 102 in the tube structure region 100a are distributed to one of the two lumens 161-1, 161-2 in the multi-lumen structure region 100b.

<1-5> Configuration example 5 of catheter shaft 100
The catheter shaft 100 of Configuration Example 5 differs from the catheter shaft 100 of Configuration Example 4 in that, while Configuration Example 4 is a unidirectional type catheter shaft 100, Configuration Example 5 is a bidirectional type catheter shaft 100.

Figures 14-16, in which the same reference numerals are used to denote parts corresponding to those in Figures 11-13, are cross-sectional views of the catheter shaft 100 of Configuration Example 5. Figure 14 is a cross-sectional view of the tube structure region 100a, Figure 15 is a cross-sectional view of the multi-lumen structure region 100b, and Figure 16 is a cross-sectional view of the catheter shaft 100 taken along a plane including E-E in Figures 14 and 15.

Compared to the configuration of the unidirectional catheter shaft 100, the bidirectional catheter shaft 100 of configuration example 5 has two pull wires 150, 151. Also, as can be seen in Figure 14, a tube 104 that houses the pull wire 151 is provided in the tube structure region 100a.

<1-6> Configuration example 6 of catheter shaft 100
17 to 19, in which the same reference numerals are assigned to parts corresponding to those in Fig. 11 to Fig. 13, are cross-sectional views of the catheter shaft 100 of Configuration Example 6. Fig. 17 is a cross-sectional view of the tube structure region 100a, Fig. 18 is a cross-sectional view of the multi-lumen structure region 100b, and Fig. 19 is a cross-sectional view of the catheter shaft 100 taken along a plane including E-E in Fig. 17 and Fig. 18.

Compared to Configuration Example 4 shown in Figures 11-13, the catheter shaft 100 of Configuration Example 6 has an additional lumen 164 formed in the multi-lumen structure region 100b, as can be seen in Figure 18. That is, in Configuration Example 6, five lumens 161-1, 161-2, 162, 163, and 164 are formed in the multi-lumen structure region 100b. Of these five lumens 161-1, 161-2, 162, 163, and 164, lead wires 140 are arranged in lumens 161-1 and 161-2, pull wire 150 is arranged in lumen 162, and lumens 163 and 164 are empty lumens.

<1-7> Configuration example 7 of catheter shaft 100
The catheter shaft 100 of Configuration Example 7 differs from the catheter shaft 100 of Configuration Example 6 in that, while Configuration Example 6 is a unidirectional type catheter shaft 100, Configuration Example 7 is a bidirectional type catheter shaft 100.

Figures 20-22, in which parts corresponding to those in Figures 17-19 are assigned the same reference numerals, are cross-sectional views of the catheter shaft 100 of Configuration Example 7. Figure 20 is a cross-sectional view of the tube structure region 100a, Figure 21 is a cross-sectional view of the multi-lumen structure region 100b, and Figure 22 is a cross-sectional view of the catheter shaft 100 taken along a plane including E-E in Figures 20 and 21.

Compared to the configuration of the unidirectional catheter shaft 100, the bidirectional catheter shaft 100 of configuration example 7 has two pull wires 150, 151.

<1-7> Summary of Embodiment 1 As described above, according to this embodiment, intracardiac defibrillation is performed using two intracardiac defibrillation catheters 1 and 2. This allows the position of the intracardiac defibrillation catheter 1 on the right atrium (RA) side to be changed independently of the intracardiac defibrillation catheter 2 on the left atrium (CS) side, thereby making it possible to lower the defibrillation threshold.

Furthermore, the catheter shafts 100 of the two intracardiac defibrillation catheters 1 and 2 have a tube structure region 100a arranged in a first longitudinal section of the catheter shaft 100 and having a luminal structure composed of multiple tubes 101, 102, 103, and 104; a multi-lumen structure region 100b arranged in a second longitudinal section different from the first longitudinal section of the catheter shaft 100 and having a luminal structure in which multiple lumens 161, 162, 163, and 164 are formed; a lead wire 140 extending into the lumen of the tube structure region 100a and the lumen of the multi-lumen structure region 100b and having one end connected to the electrodes 111, 121, and 131; and a pull wire 151 extending continuously through both the lumen of the tube structure region 100a and the lumen of the multi-lumen structure region 100b.

When inserting a catheter shaft into a patient's blood vessels and cardiac chambers, kinking is more likely to occur mechanically toward the tip, so it is desirable for the catheter shaft to be configured so that kinking is less likely toward the tip. On the other hand, when inserting a catheter shaft into a patient's blood vessels and cardiac chambers, it is desirable for the catheter shaft to be configured so that torque transmission is higher (in other words, the pushing force is stronger) toward the base end.

Taking this into consideration, in this embodiment, the multi-lumen structure region 100b is arranged on the distal end side, and the tube structure region 100a is arranged on the proximal end side.

Let me explain why.

In other words, the tube structure region 100a is a hollow structure that is prone to kinking, making it disadvantageous as a distal end configuration. In contrast, the multi-lumen structure region 100b has a large amount of resin, a low risk of kinking, and high viscosity and followability, making it advantageous as a distal end configuration. Therefore, the multi-lumen structure region 100b was adopted as the distal end configuration.

Here, it is possible to consider constructing the entire catheter shaft from the base end to the tip end using a multi-lumen structure, but it was thought that a multi-lumen structure would be less advantageous than a tube structure in terms of enhancing the torque transmission required for the base end structure.

The inventors noticed that tube structures offer a high degree of design freedom and are easy to process. Because a large proportion of a tube structure is hollow, reinforcing bodies can be easily installed in these areas, improving torque transmission.

Figure 23, in which parts corresponding to those in Figure 20 are assigned the same reference numerals, and Figure 24, in which parts corresponding to those in Figure 22 are assigned the same reference numerals, show an example in which a coil K1 is provided as a reinforcing body. As can be seen from Figures 23 and 24, the coil K1 is provided in the tube structure region 100a. In the example shown, the coil K1 is arranged along the inner circumferential surface of the tube 101. This allows the coil K1 to improve the torque transmission performance of the tube structure region 100a.

In this embodiment, the coil K1 is used as a reinforcing member in the tube structure region 100a. However, a metal tube or wire, for example, may also be used as the reinforcing member. The configuration of providing a reinforcing member in the tube structure region 100a to enhance torque transmission is preferably also applied to other embodiments described below.

In this way, the configuration of this embodiment takes into account the characteristics of the tube structure and multi-lumen structure, and by arranging the multi-lumen structure region 100b on the distal end and the tube structure region 100a on the proximal end, it is possible to realize a catheter shaft 100 that is resistant to kinking, has high tenacity and tracking ability on the distal end, and has high torque transmission ability on the proximal end.

This allows for the realization of an intracardiac defibrillation catheter that is easy to operate and allows the operator to easily place the defibrillation electrodes at the desired position.

<2> Second embodiment
In this embodiment, as shown in Fig. 25, a description will be given of the configuration of an intracardiac defibrillation catheter when intracardiac defibrillation is performed using a single intracardiac defibrillation catheter 10. The intracardiac defibrillation catheter 10 is a catheter having both RA and CS electrodes.

The catheter shaft of the intracardiac defibrillation catheter 10 is inserted into the right atrium 3 and coronary sinus 4 via the inferior vena cava. At this time, the RA electrode group is placed in the right atrium (RA) 3, and the CS electrode group is placed in the coronary sinus (CS) 4.

Figure 26 is an external view showing the overall configuration of the intracardiac defibrillation catheter 10 of this embodiment. The intracardiac defibrillation catheter 10 has a catheter shaft 1100, a handle portion 1200, and connectors 1301 and 1302.

The catheter shaft 1100 is provided with an RA electrode group 1110, a CS electrode group 1120, and an inspection electrode group 1130. The RA electrode group 1110 consists of multiple (eight in this embodiment) ring-shaped electrodes 20 arranged at a predetermined distance, the CS electrode group 1120 consists of multiple (eight in this embodiment) ring-shaped electrodes 1121 arranged at a predetermined distance, and the inspection electrode group 1130 consists of multiple (four in this embodiment) ring-shaped electrodes 1131 arranged at a predetermined distance.

The catheter shaft 1100 has a tube structure region 1100a and a multi-lumen structure region 1100b. The tube structure region 1100a is located in a first longitudinal section of the catheter shaft 100 and has a luminal structure composed of one or more tubes. The multi-lumen structure region 1100b is located in a second longitudinal section of the catheter shaft 1100 that is different from the first longitudinal section and has a luminal structure in which multiple lumens are formed. The tube structure region 1100a and the multi-lumen structure region 1100b will be described in detail later.

Connectors 1301 and 1302 are connected to a defibrillator (not shown).

When performing treatment such as intracardiac defibrillation, the defibrillator supplies electrical energy to the RA electrode group 1110 and the CS electrode group 1120. On the other hand, when measuring an intracardiac electrocardiogram, the defibrillator obtains the intracardiac electrocardiogram using the potentials of the RA electrode group 1110, the CS electrode group 1120, and the testing electrode group 1130.

<2-1> Configuration example 1 of catheter shaft 1100
Next, the configuration of the catheter shaft 1100 of this embodiment will be described in detail. Figures 27, 28, 29, and 30 are cross-sectional views showing the AA cross section, the BB cross section, the CC cross section, and the LL cross section (LL cross section in Figures 27, 28, and 29), respectively, of Figure 26.

Figures 27 and 28 are cross-sectional views of the tube structure region 1100a. As can be seen from Figures 27 and 28, the catheter shaft 1100 has multiple tubes 1101, 1102, and 1103 arranged concentrically in the tube structure region 1100a. Specifically, each of the tubes 1101, 1102, and 1103 has a different diameter, with tube 1102 arranged in the hollow portion of tube 1101, tube 1103 arranged in the hollow portion of tube 1102, and tube 1104 arranged in the hollow portion of tube 1103.

Each of the tubes 1101, 1102, 1103, and 1104 is made of a resin with insulating properties. Specifically, each of the tubes 1101, 1102, 1103, and 1104 is made of, for example, polyvinyl chloride, polyurethane, polyamide, fluorine-based resin, or polyimide. Of the multiple tubes 1101, 1102, 1103, and 1104, the outermost tube 1101 is thicker than the other tubes 1102, 1103, and 1104. This reliably prevents blood from entering the interior of the tube 1101 and increases the reliability of the fixation of the electrodes 1111, 1121, and 1131 to the tube 1101.

Lead wires 1132 connected to electrodes 1131 of the testing electrode group 1130 are arranged in the gap between tubes 1101 and 1102. In this embodiment, the testing electrode group 1130 has four electrodes 1131, so four lead wires 1132 are provided, one connected to each electrode 1131. Furthermore, a pull wire 1140 is provided inside tube 1101.

Lead wires 1112 connected to electrodes 1111 of the RA electrode group 1110 are arranged in the gap between tube 1102 and tube 1103. In this embodiment, there are eight electrodes 1111 in the RA electrode group 1110, so eight lead wires 1112 are provided, one connected to each electrode 1111.

Lead wires 1122 connected to the electrodes 1121 of the CS electrode group 1120 are arranged in the internal space of the tube 1103. In this embodiment, the CS electrode group 1120 has eight electrodes 1121, so eight lead wires 1122 are provided, one connected to each electrode 1121.

As a result, the lead wires 1112, 1122, and 1132 are separated by the tubes 1102 and 1103, and are electrically insulated from each other. An insulating film is formed on the surface of each of the lead wires 1112, 1122, and 1132, and each of the lead wires 1112, 1122, and 1132 is also insulated by this insulating film.

Here, lead wires connected to the same electrode group have approximately the same potential during intracardiac defibrillation, but large potential differences occur between lead wires connected to different electrode groups during intracardiac defibrillation, so insulation by an insulating film on the surface of the lead wire alone is insufficient. Therefore, in this embodiment, multiple tubes 1102, 1103 arranged concentrically provide insulation between lead wires 1132, 1112, 1122 connected to different electrode groups 1130, 1110, 1120.

Lead wires 1112, 1122, and 1132 pass through the handle portion 1200 and are connected to the defibrillator via connectors 1301 and 1302.

Figure 29 is a cross-sectional view of the multi-lumen structure region 1100b. As can be seen from Figure 29, the catheter shaft 1100 has multiple lumens 1151, 1152, and 1153 formed in the multi-lumen structure region 1100b. The lumens 1151, 1152, and 1153 are formed by drilling a cylindrical core 1160 of the catheter shaft 1100 in the longitudinal direction of the catheter shaft 1100.

The core 1160 is made of, for example, a low-hardness nylon elastomer. The outer periphery of the core 1160 may be covered with an outer shell made of a high-hardness nylon elastomer. The core 1160 and the lumens 1151, 1152, and 1153 are separated by fluororesin layers 1151a, 1152a, and 1153a.

However, the configuration of the multi-lumen structure region 1100b is not limited to this. The multi-lumen structure region 1100b only needs to have at least a core 1160 and multiple lumens drilled in the longitudinal direction of the core 1160.

The hollow portions of lumens 1151 and 1152 are perfectly circular. In contrast, the hollow portion of lumen 1153 is not perfectly circular. Specifically, lumen 1153 is shaped like an oval coin. Alternatively, lumen 1153 may be described as having two opposing straight lines and two opposing curved lines. Furthermore, the hollow portion of lumen 1153 may be elliptical or nearly elliptical, oval (racetrack) shaped, or any other shape. For example, the cross-sectional shape of lumen 1153 may be shaped like glasses or a gourd, thereby creating a depression (waist). By adopting such a shape and positioning lumens 1151 and 1152 near the depression (waist), the positions of lumens 1151 and 1152 can be more stabilized. Stabilizing the positions of lumens 1151 and 1152 leads to improved operation accuracy. Furthermore, lumen 1153 may have a hollow portion that is a composite combination of different shapes, such as a perfect circle or rectangle. Lumen 1153 is formed along the diameter of core 1160, and lumens 1162 and 1163 are formed on either side of lumen 1161.

A pull wire 1140 is inserted through the lumen 1151. A lead wire 1122 connected to an electrode 1121 of the CS electrode group 1120 is inserted through the lumen 1153. In this embodiment, nothing is inserted through the lumen 1152. Therefore, the lumen 1152 does not need to be formed.

The base end of the pull wire 1140 is connected to the dial 1201 of the handle portion 1200. The tip end of the pull wire 1140 is connected to the cap 1150. The tip end of the pull wire 1140 may also be connected to the core 1160. As can be seen in Figures 27, 28, and 29, the pull wire 1140 passes through a position eccentric from the center toward the outer periphery of the catheter shaft 1100. As a result, when the user rotates the dial 1201, the pull wire 1140 is pulled, causing the tip portion of the catheter shaft 1100 to bend downward (in the -a direction) in Figure 26, for example, thereby allowing the catheter shaft 1100 to be advanced in the desired direction within the blood vessel and heart.

The configuration of the catheter shaft 1100 of this embodiment will be described in more detail using Figure 30. Figure 30 is a cross-sectional view of the catheter shaft 1100 taken along a plane including L-L in Figures 26-29.

The proximal ends of tubes 1101, 1102, 1103, and 1104 are joined to the handle portion 1200.

A cap 1150 (Figure 26) is attached to the tip of the tube 1101. The cap 1150 is made of, for example, an X-ray opaque material and functions as a marker.

Tube 1102 extends further distally than electrode 1131 of the testing electrode group 1130 and terminates proximally than electrode 1111 of the RA electrode group 1110. Tube 1103 extends further distally than electrode 1111 of the RA electrode group 1110 and terminates proximally than electrode 1121 of the CS electrode group 1120.

Each electrode 1131 of the testing electrode group 1130 is connected to each lead wire 1132 arranged between tube 1101 and tube 1102.

Each electrode 1111 of the RA electrode group 1110 is connected to a lead wire 1112 arranged between tube 1102 and tube 1103. Here, each lead wire 1112 is led out of tube 1102 from the opening at the tip of tube 1102 and connected to each electrode 1111.

Each electrode 1121 of the CS electrode group 1120 is connected to a lead wire 1122 arranged in the internal space of the tube 1103 and the lumen 1153. Here, each lead wire 1122 is led out of the tube 1103 from the opening at the tip of the tube 1103, passes through the lumen 1153, and is connected to each electrode 1121.

The electrodes 1111, 1121, 1131 and the lead wires 1112, 1122, 1132 are connected by welding, for example. The tube 1101 is also formed with insertion holes through which the lead wires 1112, 1122, 1132 can be inserted. After the lead wires 1112, 1122, 1132 are passed through the insertion holes, the ring-shaped electrodes 1111, 1121, 1131 are attached to the tube 1101 by crimping, for example. The method of attaching the electrodes 1111, 1121, 1131 to the tube 1101 is not limited to this. The key point is that the electrodes 1111, 1121, 1131 should be attached in such a way that blood does not enter the tube 1101 through the insertion holes. Furthermore, in consideration of smooth insertion of the catheter shaft 1100 into the cardiac chamber, it is preferable to attach the electrodes 1111, 1121, and 1131 so that the step between the tube 1101 and the electrodes 1111, 1121, and 1131 is as small as possible.

<2-2> Configuration example 2 of catheter shaft 1100
In the above section <2-1>, we have described a unidirectional type catheter shaft 1100, i.e., a catheter shaft 1100 whose distal end can be bent in only one direction (-a direction) using a single pull wire 1140. In this configuration example 2, we will describe the configuration of a bidirectional type catheter shaft 1100.

Figures 31-34, in which the same reference numerals are used to denote parts corresponding to those in Figures 27-30, show the configuration of a bidirectional catheter shaft 1100. Figures 31 and 32 are cross-sectional views of the tube structure region 1100a, Figure 33 is a cross-sectional view of the multi-lumen structure region 1100b, and Figure 34 is a cross-sectional view of the catheter shaft 1100 taken along a plane including L-L in Figures 31-33.

Compared to the configuration of the unidirectional catheter shaft 1100, the bidirectional catheter shaft 1100 of this configuration example 2 has two pull wires 1140, 1141. Also, as can be seen from Figures 29 and 34, the tube structure region 1100a is provided with a tube 1105 that houses the pull wire 1141.

The two pull wires 1140, 1141 are wound around the dial 201 in opposite directions. This allows the tip of the catheter shaft 100 to be selectively bent in one of two directions (-a direction, +a direction) depending on the direction of rotation of the dial 201.

<2-3> Summary of Embodiment 2 As described above, according to this embodiment, the catheter shaft 1100 is divided into a tube structure region 1100a, which is arranged in a first section in the longitudinal direction of the catheter shaft 1100 and has a tubular structure formed by a plurality of tubes 1101, 1102, 1103 arranged concentrically, and a multi-lumen region 1100b, which is arranged in a second section different from the first section in the longitudinal direction of the catheter shaft 1100 and has a tubular structure formed with a plurality of lumens 1151, 1152, 1153. The device has a lumen structure region 1100b, a group of lead wires 1112, 1122, 1132 that extend continuously through both the lumen of the tube structure region 1100a and the lumen of the multi-lumen structure region 1100b and have one end connected to electrodes 1111, 1121, 1131, and a pull wire 150 that extends continuously through both the lumen of the tube structure region 1100a and the lumen of the multi-lumen structure region 1100b and have one end connected to the operating portion (handle portion 1200).

As a result, similar to embodiment 1, by arranging the multi-lumen structure region 1100b on the distal end side and the tube structure region 1100a on the proximal end side, it is possible to realize a catheter shaft 100 that is resistant to kinking, has high tenacity and tracking ability on the distal end side, and has high torque transmission ability on the proximal end side.

This allows for the realization of an intracardiac defibrillation catheter that is easy to operate and allows the operator to easily place the defibrillation electrodes at the desired position.

<3> Third embodiment
In this third embodiment, as described in the above item <1-3>, another configuration example will be described in which a reinforcing plate is provided on the catheter shaft 100. In the drawings used in the following description, the same reference numerals are used to designate the same components as those already described.

<3-1> Configuration example 1 (when there is one reinforcing plate)
Figures 35, 36, and 37 are cross-sectional views of the catheter shaft 100 of Configuration Example 1. Figure 35 is a cross-sectional view of the catheter shaft 100 taken along a plane including B-B in Figure 2, and Figure 36 is a cross-sectional view of the catheter shaft 100 taken along a plane including A-A in Figure 2. Figure 37 is a cross-sectional view of the catheter shaft 100 taken along a plane including E-E in Figures 35 and 36.

The catheter shaft 100 of this configuration example differs from the configuration described in item <1-3> in the following respects.

As can be seen by comparing Figure 35 with Figure 10, in this configuration example, a resin coating 180a is formed on the surface of the metal reinforcing plate 180. This prevents damage to the lead wire 140 caused by contact between the lead wire 140 and the reinforcing plate 180, and protects the lead wire 140.

As can be seen by comparing Figure 36 with Figure 11, the catheter shaft 100 of this configuration example has a tube structure at the A-A cross section in the longitudinal direction of the shaft, and a coil K1 is arranged along the inner surface of the tube 101. Two pull wires 150 and 151 are provided in the tubes 103 and 104, respectively. A plurality of lead wires 140 are also arranged in a dispersed manner within the tube 101.

Furthermore, as can be seen by comparing Figure 37 with Figure 24, the catheter shaft 100 of this configuration example is provided with a reinforcing plate 180 in addition to the configuration described in Figure 24.

The reinforcing plate 180 extends longitudinally through the multi-lumen structure region 100b, with a portion of its base end extending into the tube structure region 100a. A portion of the rear end of the reinforcing plate 180 overlaps a portion of the distal end of the coil K1, which serves as a reinforcing body, in the longitudinal direction.

<3-2> Configuration example 2 (when there are two reinforcing plates)
38, 39, 40, and 41 are cross-sectional views of the catheter shaft 100 of Configuration Example 2. Fig. 42 shows the positions of the cross sections.

Figure 38 is a cross-sectional view of the catheter shaft 100 taken along a plane including CC in Figure 42, Figure 39 is a cross-sectional view of the catheter shaft 100 taken along a plane including B-B in Figure 42, and Figure 40 is a cross-sectional view of the catheter shaft 100 taken along a plane including A-A in Figure 42. Figure 41 is a cross-sectional view of the catheter shaft 100 taken along a plane including E-E in Figures 38-40.

As can be seen from Figures 39 and 41, in Configuration Example 2, two metal reinforcing plates 180 are provided, compared to the configuration described in Configuration Example 1 in section <3-1> above.

<3-3> Configuration example 3 (when there are three reinforcing plates)
43, 44, 45, and 46 are cross-sectional views of the catheter shaft 100 of Configuration Example 3.

Figure 43 is a cross-sectional view of the catheter shaft 100 taken along a plane including CC in Figure 42, Figure 44 is a cross-sectional view of the catheter shaft 100 taken along a plane including B-B in Figure 42, and Figure 45 is a cross-sectional view of the catheter shaft 100 taken along a plane including A-A in Figure 42. Figure 46 is a cross-sectional view of the catheter shaft 100 taken along a plane including E-E in Figures 43-45.

As can be seen from Figures 44 and 46, in Configuration Example 3, three metal reinforcing plates 180 are provided, compared to the configuration described in Configuration Example 1 in section <3-1> above.

<3-4> Summary of the Third Embodiment The provision of the metal reinforcing plate (flat plate) 180 improves the flatness of the curved catheter shaft 100. In other words, bending in directions other than the desired direction can be suppressed.

Furthermore, by providing multiple reinforcing plates (flat plates) 180, it is possible to make the curved shape of the tip of the catheter shaft 100 asymmetric in the +a and -a directions. Furthermore, the more reinforcing plates (flat plates) 180 are used, the more reinforcement can be provided for the curved base end of the tip of the catheter shaft 100. Here, the more reinforcing plates (flat plates) 180 are used, the less likely that portion will bend. As a result, the way the tip electrode portion bends changes depending on the number of reinforcing plates (flat plates) 180, and the curved shape of the tip changes. In other words, by appropriately selecting the number of reinforcing plates (flat plates) 180, it is possible to increase the variety of curved shapes at the curved tip.

The reinforcing plate 180 can be made of a material such as NiTi or SUS. If multiple reinforcing plates 180 are used, the materials for each reinforcing plate 180 may be different. For example, if a reinforcing plate (flat plate) 180 made by stacking NiTi and SUS is used, the hardness characteristics of each material can make the curved shape of the tip electrode portion asymmetric in the +a and -a directions, further increasing the variety of curved shapes. Furthermore, if a single reinforcing plate 180 is used, the material may be uniform, or may vary, for example, along the longitudinal direction.

In addition, with regard to the bidirectional type, a reinforcing plate 180 is located within the lumen of the multi-lumen structure, and the reinforcing plate 180 is fixed at the tip and rear of the tube, preventing the reinforcing plate 180 from twisting within the catheter, improving torque transmission throughout the catheter.

In the above-described embodiment, the resin coating 180a is formed on the entire surface of the reinforcing plate 180, but the resin coating 180a may be formed only on a portion of the surface of the reinforcing plate 180, or the resin coating 180a may not be formed at all.

As can be seen from Figures 41 and 46, in the above-described embodiment, the region in which the multiple reinforcing plates 180 are overlapped extends from the base end of the reinforcing plate 180 to the base end of the ring-shaped electrode 111 (121, 122), but the region in which the multiple reinforcing plates 180 are overlapped is not limited to this. For example, the multiple reinforcing plates 180 may be overlapped further toward the tip end.

In the above-described embodiment, the lead wire 140 and pull wires 150, 151 are arranged inside the coil K1 serving as the reinforcing body, but this is not limiting; the lead wire 140 and pull wires 150, 151 may also be arranged outside the coil K1. Furthermore, the reinforcing body is not limited to the coil K1, and may be, for example, a pipe. Furthermore, a resin coating may be formed on the surface of the reinforcing body.

<4> Other Embodiments The above-described Embodiments 1 to 3 are merely examples of specific embodiments of the present invention, and the technical scope of the present invention should not be construed as being limited by these. In other words, the present invention can be embodied in various forms without departing from the gist or main features thereof.

The number and arrangement of lumens in the multi-lumen structure region and the number and arrangement of tubes in the tube structure region are not limited to the examples shown in embodiments 1-3.

Furthermore, the number and arrangement of lead wires and pull wires arranged in the multi-lumen structure region and the tube structure region are not limited to those described in the embodiment. Furthermore, the pull wires are not limited to metal wires, but may also be wires made of resin or other materials. Therefore, the present disclosure can be implemented by replacing the pull wires in this specification with the term "cord member."

Furthermore, the configurations described in embodiments 1-3 above can be implemented in appropriate combinations.

The intracardiac defibrillation catheter disclosed herein is useful, for example, as an intracardiac defibrillation catheter used in treatments such as intracardiac defibrillation.

1, 2, 10 Intracardiac defibrillation catheter 100, 1100 Catheter shaft 100a, 1100a Tube structure region 100b, 1100b Multi-lumen structure region 101 to 104, 1101 to 1105 Tube 110, 1110 RA electrode group 111, 121, 131, 1111, 1121, 1131 Electrode 120, 1120 CS electrode group 130, 1130 Test electrode group 140, 1112, 1122, 1132 Lead wire 150, 151, 1140, 1141 Pull wire 161 to 164, 1151 to 1153 Lumen 170, 1160 Core 180 Reinforcing plate 180a Resin coating 200, 1200 Handle

Claims (12)

An intracardiac defibrillation catheter having a catheter shaft with electrodes arranged on its surface and an operation unit connected to a proximal end side of the catheter shaft,
The catheter shaft
a tube structure region disposed in a first section in the longitudinal direction of the catheter shaft and having a tubular structure formed by a plurality of tubes separate from one another;
a multi-lumen structure region disposed in a second section of the catheter shaft that is located on the distal end side of the first section in the longitudinal direction, the multi-lumen structure region having a tubular structure in which multiple lumens are formed in one core;
a group of lead wires extending continuously through both the lumen of the tube structure region and the lumen of the multi-lumen structure region, one end of which is connected to the electrode;
a cord-like member that extends continuously across both the lumen of the tube structure region and the lumen of the multi-lumen structure region, and one end of which is connected to the operation unit;
Equipped with
Intracardiac defibrillation catheter. The plurality of tubes in the tube structure region include a plurality of tubes arranged concentrically.
The intracardiac defibrillation catheter of claim 1 . At least one lumen in the multi-lumen structure region has a hollow cross section that is not a perfect circle when the catheter shaft is cut along a plane perpendicular to the longitudinal direction.
The intracardiac defibrillation catheter of claim 1 . The hollow cross section of the at least one lumen that is not a perfect circle is elliptical or approximately elliptical.
The intracardiac defibrillation catheter of claim 3 . A reinforcing plate is disposed in the at least one lumen whose hollow cross section is not a perfect circle.
The intracardiac defibrillation catheter of claim 3 . The reinforcing plate is restricted in rotation within the lumen around the longitudinal direction of the catheter shaft as a rotation axis.
6. The intracardiac defibrillation catheter of claim 5. the reinforcing plate is made of a material having a higher hardness than the core in the multi-lumen structure region of the catheter shaft.
6. The intracardiac defibrillation catheter of claim 5. A plurality of the reinforcing plates are provided.
6. The intracardiac defibrillation catheter of claim 5. The base end side of the reinforcing plate extends to the tube structure region.
6. The intracardiac defibrillation catheter of claim 5. The number of the reinforcing plates is greater in the base end region than in the tip end region.
9. The intracardiac defibrillation catheter of claim 8. the lead wire group is disposed in a first lumen in the multi-lumen structure region;
The cord-like member is disposed in the second lumen in the multi-lumen structure region.
The intracardiac defibrillation catheter of claim 1 . the electrodes in the tube structure region are an RA electrode group,
The electrodes in the multi-lumen structure region are a CS electrode group.
The intracardiac defibrillation catheter of claim 1 .