JP7514403B2 - Catheter System - Google Patents

Description

The present invention relates to a catheter system, and more particularly to an intracardiac defibrillation catheter system comprising a defibrillation catheter to be inserted into a cardiac cavity and a power supply device that applies a DC voltage to the electrodes of the defibrillation catheter.

The applicant has developed an intracardiac defibrillation catheter system for performing defibrillation treatment of a heart suffering from atrial fibrillation or the like, which comprises a defibrillation catheter that is inserted into a cardiac cavity to perform defibrillation, a power supply unit that applies a DC voltage to the electrodes of the defibrillation catheter, and an electrocardiograph; the defibrillation catheter comprises a first electrode group consisting of a plurality of ring-shaped electrodes attached to the distal end region of an insulating tube member, a second electrode group consisting of a plurality of ring-shaped electrodes attached to the tube member at a distance from the first electrode group to the proximal end side, a first lead wire group consisting of a plurality of lead wires whose tips are connected to each of the electrodes constituting the first electrode group, and a second lead wire group consisting of a plurality of lead wires whose tips are connected to each of the electrodes constituting the second electrode group; the power supply unit comprises a DC power supply unit, a catheter connection connector that is connected to the proximal end side of the first lead wire group and the second lead wire group of the defibrillation catheter, an electrocardiograph connection connector that is connected to an input terminal of the electrocardiograph, and controls the DC power supply unit based on the input of an external switch and supplies a DC voltage to the DC power supply unit. and a switching unit consisting of a one-circuit, two-contact changeover switch, with the catheter connection connector connected to a common contact, the electrocardiograph connection connector connected to a first contact, and the arithmetic processing unit connected to a second contact; when a cardiac potential is measured using electrodes constituting a first and/or second electrode group of the defibrillation catheter, the first contact is selected in the switching unit, and cardiac potential information from the defibrillation catheter is input to the electrocardiograph via the catheter connection connector, the switching unit, and the electrocardiograph connection connector of the power supply device, and when defibrillation is performed using the defibrillation catheter, the contact of the switching unit is switched to the second contact by the arithmetic processing unit of the power supply device, and voltages of mutually opposite polarities are applied from the DC power supply unit to the first electrode group and the second electrode group of the defibrillation catheter via the output circuit of the arithmetic processing unit, the switching unit, and the catheter connection connector (see Patent Document 1 below).

This intracardiac defibrillation catheter system can reliably supply electrical energy necessary and sufficient for defibrillation to a heart suffering from atrial fibrillation during cardiac catheterization. When defibrillation treatment is not required, the defibrillation catheter constituting the catheter system can be used as an electrode catheter for measuring cardiac potentials.
In defibrillation treatment using the intracardiac defibrillation catheter system described in Patent Document 1, the mode of the power supply device is switched to the "defibrillation mode" for a certain period of time (e.g., one second) by inputting a mode changeover switch of the power supply device in the "cardiac potential measurement mode". During this time, the impedance between the first electrode group and the second electrode group of the defibrillation catheter is measured. Then, the applied energy setting switch is input to set the electric energy to be applied when performing defibrillation, and the charging switch is input to charge the DC power supply unit with a voltage determined based on the measured impedance and the set electric energy. After charging is completed, the energy application switch is input to switch the contact of the switching unit from the first contact to the second contact (thereby switching the mode of the power supply device from the "cardiac potential measurement mode" to the "defibrillation mode"), and DC voltages of different polarities are applied to the first electrode group and the second electrode group of the defibrillation catheter from the DC power supply unit that has received a control signal from the arithmetic processing unit via the output circuit of the arithmetic processing unit, the switching unit, and the catheter connection connector.

Japanese Patent No. 4545216

In the defibrillation catheter that constitutes the catheter system of Patent Document 1, it is possible that some of the multiple lead wires that constitute the first lead wire group and the multiple lead wires that constitute the second lead wire group are broken.
Defibrillation catheters with some of the lead wires broken not only make it impossible to perform the intended treatment, but also increase the energy applied to electrodes other than the one connected to the broken lead wire (concentration of defibrillation energy), posing a risk of damage to the patient's intracardiac tissue at the location of that electrode.
In addition, lead wire breakage may occur during defibrillation treatment due to the influence of peak current caused by defibrillation or due to the patient's body movements.

However, it is extremely difficult to know that some of the lead wires are broken. For example, when some of the lead wires are broken, the impedance measured between the first electrode group and the second electrode group increases. However, since the impedance value between the electrode groups varies depending on the patient, even if an increase in impedance is observed, it cannot be immediately determined that it is due to a break in the lead wires.
In addition, electrocardiograms measured using electrodes connected to broken leads tend to have noise, but it is not possible to determine whether this noise is due to a broken lead or not. In particular, electrocardiograms taken immediately after defibrillation are prone to noise, and the cause of this noise is often something other than a broken lead.

The present invention has been made based on the above circumstances.
A first object of the present invention is to provide a defibrillation catheter system capable of quickly and reliably detecting breakage of a lead wire constituting a defibrillation catheter.
A second object of the present invention is to provide a defibrillation catheter system that can prevent defibrillation from being performed when a lead wire is broken.
A third object of the present invention is to provide a defibrillation catheter system that can identify a broken lead wire (the electrode to which the lead wire is connected) and allow an operator to recognize the identified lead wire.
A fourth object of the present invention is to provide a defibrillation catheter system that can detect the breakage of a lead wire even if the lead wire breaks during defibrillation therapy.
A fifth object of the present invention is to provide a catheter system capable of quickly and reliably detecting breakage of a lead wire constituting an electrode catheter.

(1) The intracardiac defibrillation catheter system of the present invention is a catheter system including a defibrillation catheter that is inserted into a cardiac cavity to perform defibrillation, and a power supply device that applies a DC voltage to an electrode of the defibrillation catheter,
the defibrillation catheter comprises an insulating tube member, a first DC electrode group consisting of a plurality of first electrodes attached to a distal end region of the tube member, a second DC electrode group consisting of a plurality of second electrodes attached to the distal end region of the tube member at a distance from the first DC electrode group to the proximal end side, a first lead wire group consisting of a plurality of first lead wires connected to respective tips of the first electrodes constituting the first DC electrode group, and a second lead wire group consisting of a plurality of second lead wires connected to respective tips of the second electrodes constituting the second DC electrode group;
The power supply device includes a DC power supply unit having a capacitor, and an arithmetic processing unit that controls the DC power supply unit based on an external input and has an output circuit for outputting a DC voltage from the DC power supply unit,
When defibrillation is performed by the defibrillation catheter, voltages of different polarities are applied to the first DC electrode group and the second DC electrode group of the defibrillation catheter from the DC power supply unit via the output circuit of the arithmetic processing unit,
The calculation processing unit of the power supply device is characterized in that, prior to performing defibrillation, impedance between one first electrode selected from the first DC electrode group and one second electrode selected from the second DC electrode group is measured for all of the first electrodes constituting the first DC electrode group and all of the second electrodes constituting the second DC electrode group (repeatedly until all of the first electrodes and second electrodes are selected).

(2) In the intracardiac defibrillation catheter system of the present invention, the calculation processing unit of the power supply device has an impedance measurement circuit capable of measuring an impedance between the first DC electrode group or the first electrode constituting the first DC electrode group and the second DC electrode group or the second electrode constituting the second DC electrode group,
the power supply device has a switch group including a plurality of switches connected to a base end of each of the first lead wires or a base end of each of the second lead wires, and capable of connecting each of the base ends to the output circuit or the impedance measurement circuit;
It is preferable that, prior to performing defibrillation, the calculation processing unit of the power supply device controls the switch group so that the impedance between one first electrode selected from the first DC electrode group and one second electrode selected from the second DC electrode group is measured by the impedance measurement circuit for all of the first electrodes constituting the first DC electrode group and all of the second electrodes constituting the second DC electrode group (repeated until all of the first electrodes and second electrodes have been selected).

According to a defibrillation catheter system having such a configuration, if the impedance measured between a first electrode selected from the first DC electrode group and a second electrode selected from the second DC electrode group is equal to or less than a predetermined value, it can be determined that the lead wires (first lead wire and second lead wire) connected to these electrodes are not broken, and if the measured impedance exceeds a predetermined value, it can be determined that at least one of the lead wires connected to these electrodes is broken.
Furthermore, since the impedance measurement is performed on all of the first electrodes constituting the first DC electrode group and all of the second electrodes constituting the second DC electrode group (the impedance measurement is repeated until all of the constituent electrodes have been selected), it is possible to check for the presence or absence of breaks in all of the lead wires connected to these electrodes.

(3) In the intracardiac defibrillation catheter system of the present invention, the first DC electrode group is composed of n first electrodes (n is an integer of 2 or more), and the second DC electrode group is composed of n second electrodes;
It is preferable that the calculation processing unit of the power supply device controls (the switch group) so that the impedance between the kth (k is any integer from 1 to n) first electrode from the tip of the first DC electrode group and the kth second electrode from the tip of the second DC electrode group is measured (by the impedance measuring circuit) n times.

With a defibrillation catheter system configured in this manner, the impedance between the first electrode that is the kth (1, 2, 3, . . . n-2, n-1, n)th from the tip of the first DC electrode group and the second electrode that is the kth (1, 2, 3, . . . n-2, n-1, n)th from the tip of the second DC electrode group is measured, and by performing n measurements, it is possible to check for the presence or absence of breaks in the n first lead wires connected to each of the n first electrodes that make up the first DC electrode group and the n second lead wires connected to each of the n second electrodes that make up the second DC electrode group.
In addition, since the distance between the electrodes at which the impedance is measured is substantially the same, the influence (error) on the measurement value due to differences in the distance between the electrodes can be eliminated.

(4) In the intracardiac defibrillation catheter system of the present invention, it is preferable that the calculation processing unit of the power supply device controls the DC power supply unit so that defibrillation can be performed only when all of the measured impedances are below a predetermined value.

With a defibrillation catheter system configured in this manner, if an impedance exceeding a predetermined value is measured even once, no DC voltage is applied (defibrillation) and therefore tissue damage caused by lead wire breakage can be reliably avoided.

(5) In the intracardiac defibrillation catheter system of the present invention, it is preferable that the power supply unit is equipped with a display means, and the calculation processing unit of the power supply unit controls the display means to display the combination of the first electrode and the second electrode at which the impedance is measured when the impedance exceeds a predetermined value.

With a defibrillation catheter system configured in this manner, it is possible to determine that at least one of the lead wires connected to the first electrode and the second electrode, where an impedance exceeding a predetermined value has been measured, is broken.

(6) In the intracardiac defibrillation catheter system of (5) above, it is preferable that the calculation processing unit of the power supply device identifies the first electrode and/or the second electrode that caused the impedance measured to exceed a predetermined value, and controls the display means to display the electrode.

A defibrillation catheter system configured in this manner can identify broken lead wires and allow the operator to recognize them.

Here, the causative electrode can be identified by measuring the impedance between each of the first and second electrodes for which an impedance exceeding a predetermined value was measured, and each of the second and first electrodes for which an impedance equal to or less than the predetermined value was measured.
For example, when only the impedance between the third first electrode from the tip of the first DC electrode group and the third second electrode from the tip of the second DC electrode group exceeds a predetermined value, the impedance between the third first electrode from the tip and the second second electrode from the tip is measured, and the impedance between the second first electrode from the tip and the third second electrode from the tip is measured.

At this time, if the impedance between the third first electrode from the tip and the second second electrode from the tip exceeds a predetermined value, it can be determined that the first lead wire connected to the third first electrode from the tip is broken, and if the impedance between the second first electrode from the tip and the third second electrode from the tip exceeds a predetermined value, it can be determined that the second lead wire connected to the third second electrode from the tip is broken.

(7) In the intracardiac defibrillation catheter system of the present invention, it is preferable that the calculation processing unit of the power supply device controls so that after defibrillation is performed, the impedance between one first electrode selected from the first DC electrode group and one second electrode selected from the second DC electrode group is measured again for all of the first electrodes constituting the first DC electrode group and all of the second electrodes constituting the second DC electrode group.

With an intracardiac defibrillation catheter system configured in this manner, if a disconnection occurs after defibrillation, this can be recognized and the defibrillation treatment can be stopped to ensure the safety of the patient.

(8) In the intracardiac defibrillation catheter system described above in (7), it is preferable that the calculation processing unit of the power supply device controls so that impedance measurement is started immediately after defibrillation is performed.

With an intracardiac defibrillation catheter system configured as described above, the waiting time until the cardiac potential stabilizes after defibrillation is performed is utilized to measure impedance, thereby making it possible to effectively utilize the waiting time and shorten the time until the next defibrillation.
Here, "immediately starting impedance measurement" means, for example, starting measurement without waiting for an operation to perform the next defibrillation (for example, input of a mode change switch to switch to defibrillation/impedance measurement mode).

(9) In the intracardiac defibrillation catheter system of the present invention, it is preferable that the calculation processing unit of the power supply device further controls so that the impedance between the first DC electrode group and the second DC electrode group (between the electrode groups) is measured.

(10) The intracardiac defibrillation catheter system according to (2), further comprising an electrocardiograph,
the power supply device comprises the DC power supply unit, an external switch serving as an input means, the arithmetic processing unit, a catheter connection connector electrically connected to each of the first DC electrode group and the second DC electrode group of the defibrillation catheter, an electrocardiograph connection connector connected to an input terminal of the electrocardiograph, and a branch connection unit connected to the catheter connection connector and connected to the electrocardiograph connection connector and the arithmetic processing unit;
When measuring an intracardiac potential using the electrodes (first electrode and/or second electrode) constituting the first DC electrode group and/or the second DC electrode group of the defibrillation catheter, cardiac potential information from the defibrillation catheter is input to the electrocardiograph via the catheter connection connector, the branch connection section, and the electrocardiograph connection connector;
When defibrillation is performed by the defibrillation catheter, voltages of different polarities are applied to the first DC electrode group and the second DC electrode group of the defibrillation catheter from the DC power supply unit via the output circuit of the arithmetic processing unit, the branch connection unit, and the catheter connection connector,
When measuring the impedance between the first DC electrode group and the second DC electrode group of the defibrillation catheter, or the impedance between the first electrode and the second electrode, it is preferable that the measured impedance information is input to the arithmetic processing unit via the catheter connection connector, the branch connection portion, and an impedance measuring circuit of the arithmetic processing unit.

(11) An intracardiac defibrillation catheter system according to the present invention is a catheter system including a defibrillation catheter that is inserted into a cardiac cavity to perform defibrillation, and a power supply device that applies a DC voltage to an electrode of the defibrillation catheter,
the defibrillation catheter comprises an insulating tube member, a first DC electrode group consisting of a plurality of first electrodes attached to a distal end region of the tube member, a second DC electrode group consisting of a plurality of second electrodes attached to the distal end region of the tube member at a distance from the first DC electrode group to the proximal end side, a first lead wire group consisting of a plurality of first lead wires connected to respective tips of the first electrodes constituting the first DC electrode group, and a second lead wire group consisting of a plurality of second lead wires connected to respective tips of the second electrodes constituting the second DC electrode group;
the power supply device comprises a DC power supply unit having a capacitor and an arithmetic processing unit, the arithmetic processing unit controls the DC power supply unit based on an external input, and has an output circuit for a DC voltage from the DC power supply unit, and an impedance measurement circuit capable of measuring an impedance between the first DC electrode group and the second DC electrode group and an impedance between electrodes constituting the first DC electrode group or the second DC electrode group;
When defibrillation is performed by the defibrillation catheter, voltages of different polarities are applied to the first DC electrode group and the second DC electrode group of the defibrillation catheter from the DC power supply unit via the output circuit of the arithmetic processing unit,
The calculation processing unit of the power supply device is characterized in that, prior to performing defibrillation, for all of the first electrodes constituting the first DC electrode group and all of the second electrodes constituting the second DC electrode group (repeatedly until all of the first electrodes and second electrodes are selected), the impedance between two electrodes selected from the first DC electrode group and the second DC electrode group is measured by the impedance measurement circuit.
With an intracardiac defibrillation catheter system configured in this manner, it is possible to measure not only the impedance between the first electrode and the second electrode, but also the impedance between the same DC electrode group (between the first electrode and the first electrode and between the second electrode and the second electrode).

(12) In the intracardiac defibrillation catheter system of (11) above, it is preferable that the two electrodes selected from the first DC electrode group and the second DC electrode group are adjacent electrodes (the first electrode and/or the second electrode).
With an intracardiac defibrillation catheter system configured in this manner, the distance between the electrodes at which impedance is measured can be minimized, and the influence (error) on the measurement value caused by a large distance between the electrodes can be eliminated.

(13) In the intracardiac defibrillation catheter system of (2) or (11) above, a portion of the calculation processing unit including the impedance measurement circuit may be arranged outside the power supply device.

(14) A catheter system according to the present invention is a catheter system including an electrode catheter for performing ablation, and a power supply device for applying energy to an electrode of the electrode catheter,
The electrode catheter comprises an insulating tube member, an electrode group consisting of a plurality of electrodes attached to a distal end region of the tube member, and a lead wire group consisting of a plurality of lead wires whose distal ends are connected to the electrodes constituting the electrode group,
the power supply device includes a power supply unit and an arithmetic processing unit that controls the power supply unit based on an external input, the arithmetic processing unit having an output circuit for energy from the power supply unit and an impedance measurement circuit capable of measuring impedance between electrodes that constitute the electrode group,
When ablation is performed by the electrode catheter, energy is applied to the electrodes constituting the electrode group from the power supply unit via the output circuit of the arithmetic processing unit,
The calculation processing unit of the power supply device is characterized in that, prior to performing ablation, for all electrodes constituting the electrode group, the impedance between two electrodes selected from the electrode group is measured by the impedance measurement circuit.

(15) The catheter system described above in (14) can be suitably used to perform pulsed field ablation (PFA).

The catheter system of the present invention makes it possible to quickly and reliably detect lead wire breakage.

FIG. 1 is a block diagram showing one embodiment of an intracardiac defibrillation catheter system of the present invention. FIG. 2 is an explanatory plan view showing a defibrillation catheter constituting the catheter system shown in FIG. 1 . FIG. 2 is an explanatory plan view (for explaining dimensions and hardness) showing a defibrillation catheter constituting the catheter system shown in FIG. 1 . 3 is a cross-sectional view showing the AA section of FIG. 2. 3A and 3B are cross-sectional views showing the sections BB, CC, and DD in FIG. 2. FIG. 3 is a perspective view showing the internal structure of a handle of one embodiment of the defibrillation catheter shown in FIG. 2 is an explanatory diagram showing a schematic connection state between a connector of a defibrillation catheter and a catheter connection connector of a power supply device in the catheter system shown in FIG. 1 . FIG. 2 is a flowchart showing the operation and manipulation of the power supply device in the catheter system shown in FIG. 1 . 2 is a block diagram showing a flow of cardiac potential information in a cardiac potential measurement mode after a main power switch is turned on in the catheter system shown in FIG. 1. FIG. FIG. 2 is a block diagram showing the flow of information relating to measured impedance values between electrodes and cardiac potential information in a defibrillation/impedance measurement mode after a mode change switch is turned on in the catheter system shown in FIG. 1 . 1. FIG. 4 is a block diagram showing the flow of cardiac potential information in a cardiac potential measurement mode after a certain time has elapsed since a mode change switch was turned on in the catheter system shown in FIG. 2 is a block diagram showing the flow of cardiac potential information after an application preparation switch is turned on in the catheter system shown in FIG. 1. FIG. 2 is a block diagram showing the flow of cardiac potential information after an application execution switch is pressed in the catheter system shown in FIG. 1. FIG. 2 is a block diagram showing a state when a DC voltage is applied after an application execution switch is turned on in the catheter system shown in FIG. 1. FIG. FIG. 11 is a circuit diagram for switching between impedance measurement and application of a DC voltage, showing a state in which the impedance between a first electrode and a second electrode can be measured. FIG. 11 is a circuit diagram for switching between impedance measurement and application of a DC voltage, showing a state in which the impedance between a first DC electrode group and a second DC electrode group can be measured. FIG. 11 is a circuit diagram for switching between impedance measurement and application of a DC voltage, showing a state in which a DC voltage can be applied to a first DC electrode group and a second DC electrode group. FIG. 11 is a circuit diagram for switching between impedance measurement and application of a DC voltage, showing a state in which the impedance between adjacent first electrodes can be measured. FIG. 11 is a circuit diagram for switching between impedance measurement and application of a DC voltage, showing a state in which the impedance between adjacent second electrodes can be measured. FIG. 11 is a circuit diagram for switching between impedance measurement and application of a DC voltage, showing a state in which the impedance between a first DC electrode group and a second DC electrode group can be measured. FIG. 11 is a circuit diagram for switching between impedance measurement and application of a DC voltage, showing a state in which a DC voltage can be applied to a first DC electrode group and a second DC electrode group.

First Embodiment
As shown in FIG. 1, the intracardiac defibrillation catheter system of this embodiment includes a defibrillation catheter 100, a power supply device 700, an electrocardiograph 800, and cardiac potential measuring means 900.
As shown in Figures 2 to 6, the defibrillation catheter 100 constituting the catheter system of this embodiment includes a multi-lumen tube 10, a handle 20, a first DC electrode group 31G, a second DC electrode group 32G, a base-end potential measurement electrode group 33G, a first lead wire group 41G, a second lead wire group 42G, and a third lead wire group 43G.

As shown in Figures 4 and 5, the multi-lumen tube 10 has four lumens (first lumen 11, second lumen 12, third lumen 13, and fourth lumen 14).

In Figures 4 and 5, 15 is a fluororesin layer that separates the lumen, 16 is an inner (core) portion made of low-hardness nylon elastomer, 17 is an outer (shell) portion made of high-hardness nylon elastomer, and 18 in Figure 4 is a stainless steel wire that forms the braided braid.

The handle 20 constituting the defibrillation catheter 100 in this embodiment includes a handle body 21, a knob 22, and a strain relief 24. By rotating the knob 22, the tip of the multi-lumen tube 10 can be deflected (swung).

A first DC electrode group 31G, a second DC electrode group 32G, and a base-end potential measurement electrode group 33G are attached to the distal end region of the multi-lumen tube 10. Here, the term "electrode group" refers to a collection of multiple electrodes that are attached at close intervals (e.g., 5 mm or less) and have the same pole (same polarity) or have the same purpose.

The first DC electrode group 31G is composed of eight ring-shaped first electrodes 31 attached to the distal end region of the multi-lumen tube 10. The first electrodes 31 constituting the first DC electrode group 31G are connected to a catheter connection connector 72 of the power supply device 700 via first lead wires 41 constituting a first lead wire group 41G and a connector described later.
When the defibrillation catheter 100 is in use (placed in a heart chamber), the first DC electrode group 31G is located, for example, in the coronary sinus (CS).

The second DC electrode group 32G is composed of eight ring-shaped second electrodes 32 attached to the distal end region of the multi-lumen tube 10 at a distance from the attachment position of the first DC electrode group 31G to the proximal end side. The second electrodes 32 constituting the second DC electrode group 32G are connected to the catheter connection connector 72 of the power supply device 700 via the second lead wires 42 constituting the second lead wire group 42G and a connector described later.
When the defibrillation catheter 100 is in use (placed in a heart chamber), the second group of DC electrodes 32G is located, for example, in the right atrium (RA).

The base-side potential measurement electrode group 33G is composed of four ring-shaped third electrodes 33 attached to the tip region of the multi-lumen tube 10 at a distance to the base end from the attachment position of the second DC electrode group 32G. The third electrodes 33 constituting the base-side potential measurement electrode group 33G are connected to the catheter connection connector 72 of the power supply device 700 via third lead wires 43 constituting the third lead wire group 43G and a connector described later.
When the defibrillation catheter 100 is in use (placed in a cardiac cavity), the base-end potential measuring electrode group 33G is located, for example, in the superior vena cava (SVC).

A distal tip 35 is attached to the distal end of the defibrillation catheter 100 .
No lead wire is connected to this tip 35, and in this embodiment, it is not used as an electrode.

The first lead wire group 41G shown in Figs. 4 and 5 is a collection of eight first lead wires 41 connected to the eight first electrodes 31 constituting the first DC electrode group 31G, respectively.
Each of the eight first electrodes 31 constituting the first DC electrode group 31G can be electrically connected to the power supply device 700 via the first lead wire group 41G.

The eight first electrodes 31 constituting the first DC electrode group 31G are each connected to a different first lead wire 41. Each of the first lead wires 41 is welded at its tip portion to the inner circumferential surface of the first electrode 31 and enters the first lumen 11 from a side hole formed in the tube wall of the multi-lumen tube 10. The eight first lead wires 41 that enter the first lumen 11 extend into the first lumen 11 as the first lead wire group 41G.

The second lead wire group 42G shown in FIGS. 4 and 5 is a collection of eight second lead wires 42 connected to the eight second electrodes 32 constituting the second DC electrode group 32G, respectively.
Each of the eight second electrodes 32 constituting the second DC electrode group 32G can be electrically connected to the power supply device 700 by the second lead wire group 42G.

The eight second electrodes 32 constituting the second DC electrode group 32G are each connected to a different second lead wire 42. Each of the second lead wires 42 is welded at its tip portion to the inner circumferential surface of the second electrode 32 and enters the second lumen 12 from a side hole formed in the tube wall of the multi-lumen tube 10. The eight second lead wires 42 that enter the second lumen 12 extend into the second lumen 12 as the second lead wire group 42G.

As described above, the first lead wire group 41G extends into the first lumen 11, and the second lead wire group 42G extends into the second lumen 12, so that the two are completely insulated and isolated within the multi-lumen tube 10. Therefore, when the voltage required for defibrillation is applied, a short circuit between the first lead wire group 41G (first DC electrode group 31G) and the second lead wire group 42G (second DC electrode group 32G) can be reliably prevented.

The third lead wire group 43G shown in FIG. 4 is a collection of four third lead wires 43 connected to each of the third electrodes 33 constituting the proximal potential measurement electrode group 33G.
The third lead wire group 43G can electrically connect each of the third electrodes 33 constituting the proximal potential measurement electrode group 33G to the power supply device 700.

The four third electrodes 33 constituting the base-end potential measurement electrode group 33G are each connected to a different third lead wire 43. Each of the third lead wires 43 is welded to the inner circumferential surface of the third electrode 33 at its tip portion and enters the third lumen 13 from a side hole formed in the tube wall of the multi-lumen tube 10. The four third lead wires 43 that enter the third lumen 13 extend into the third lumen 13 as the third lead wire group 43G.

As described above, the third lead wire group 43G extending into the third lumen 13 is completely insulated and isolated from both the first lead wire group 41G and the second lead wire group 42G. Therefore, when the voltage required for defibrillation is applied, it is possible to reliably prevent a short circuit between the third lead wire group 43G (proximal potential measurement electrode group 33G) and the first lead wire group 41G (first DC electrode group 31G) or the second lead wire group 42G (second DC electrode group 32G).

In FIG. 4 and FIG. 5, 65 denotes a pull wire.
The pull wire 65 extends into the fourth lumen 14 and extends eccentrically with respect to the central axis of the multi-lumen tube 10. The distal end portion of the pull wire 65 is fixed to the distal tip 35 by soldering. Meanwhile, the proximal end portion of the pull wire 65 is connected to the knob 22 of the handle 20. By operating the knob 22, the pull wire 65 is pulled, thereby deflecting the distal portion of the multi-lumen tube 10.

In this embodiment, the defibrillation catheter 100 has the first lead wire group 41G, the second lead wire group 42G, and the third lead wire group 43G insulated and isolated from each other even inside the handle 20.

Figure 6 is a perspective view showing the internal structure of the handle of the defibrillation catheter 100 in this embodiment. As shown in Figure 6, the base end of the multi-lumen tube 10 is inserted into the tip opening of the handle 20, thereby connecting the multi-lumen tube 10 and the handle 20.

A cylindrical connector 50 is built into the proximal end of the handle 20 .
Within the handle 20, three insulating tubes (first insulating tube 26, second insulating tube 27, third insulating tube 28) extend, through which each of the three lead wire groups (first lead wire group 41G, second lead wire group 42G, third lead wire group 43G) is inserted.

The tip of the first insulating tube 26 is inserted into the first lumen 11 of the multi-lumen tube 10, whereby the first insulating tube 26 is connected to the first lumen 11 through which the first lead wire group 41G extends.
The first insulating tube 26 extends through the inner hole of the first protective tube 61 extending inside the handle 20 to the vicinity of the connector 50, forming an insertion passage that guides the base ends of the first lead wire group 41G to the vicinity of the connector 50.
The first lead wire group 41G extending from the base end opening of the first insulating tube 26 is separated into eight first lead wires 41, and each of these first lead wires 41 is connected and fixed by solder to each of the pin terminals arranged on the tip surface of the connector 50.

The tip of the second insulating tube 27 is inserted into the second lumen 12 of the multi-lumen tube 10, whereby the second insulating tube 27 is connected to the second lumen 12 through which the second lead wire group 42G extends.
The second insulating tube 27 extends through the inner hole of the second protective tube 62 extending inside the handle 20 to the vicinity of the connector 50, forming an insertion passage that guides the base ends of the second lead wire group 42G to the vicinity of the connector 50.
The second lead wire group 42G extending from the base end opening of the second insulating tube 27 is separated into eight second lead wires 42, and each of these second lead wires 42 is connected and fixed by solder to each of the pin terminals arranged on the tip surface of the connector 50.

The tip of the third insulating tube 28 is inserted into the third lumen 13 of the multi-lumen tube 10, whereby the third insulating tube 28 is connected to the third lumen 13 through which the third lead wire group 43G extends.
The third insulating tube 28 extends through the inner hole of the second protective tube 62 extending inside the handle 20 to the vicinity of the connector 50, forming an insertion passage that guides the base ends of the third lead wire group 43G to the vicinity of the connector 50.
The third lead wire group 43G extending from the base end opening of the third insulating tube 28 is separated into four third lead wires 43, and each of these third lead wires 43 is connected and fixed by solder to each of the pin terminals arranged on the tip surface of the connector 50.

According to the defibrillation catheter 100 of the present embodiment having the above-mentioned configuration,
With the first lead wire group 41G extending into the insulating tube 26, the second lead wire group 42G extending into the second insulating tube 27, and the third lead wire group 43G extending into the third insulating tube 28, the first lead wire group 41G, the second lead wire group 42G, and the third lead wire 43G can be completely insulated and isolated even inside the handle 20.

As shown in FIG. 1, the power supply unit 700 constituting the catheter system of this embodiment includes a DC power supply unit 71, a catheter connection connector 72, an electrocardiogram connection connector 73, an external switch (input means) 74, an arithmetic processing unit 75, a first ON/OFF switch 761 and a second ON/OFF switch 762 constituting a branch connection unit 76, and an electrocardiogram input connector 77.

The DC power supply unit 71 has a built-in capacitor.

The proximal ends of the first lead wire group 41G, the second lead wire group 42G, and the third lead wire group 43G of the defibrillation catheter 100 are connected to the catheter connector 72.
As a result, the catheter connection connector 72 is electrically connected to each of the first DC electrode group 31G, the second DC electrode group 32G, and the base-end potential measurement electrode group 33G.

The catheter connection connector 72 is connected to the connector 50 of the defibrillation catheter 100 and is electrically connected to the base end sides of the first lead wire group 41G, the second lead wire group 42G and the third lead wire group 43G.

As shown in FIG. 7, the connector 50 of the defibrillation catheter 100 and the catheter connector 72 of the power supply device 700 are connected by a connector cable C1.
A pin terminal 51 (actually eight terminals) to which the eight first lead wires 41 constituting the first lead wire group are connected and fixed, and a terminal 721 (actually eight terminals) of a catheter connection connector 72,
Pin terminals 52 (actually eight terminals) to which the eight second lead wires 42 constituting the second lead wire group are connected and fixed, and terminals 722 (actually eight terminals) of a catheter connection connector 72,
The pin terminals 53 (actually four terminals) to which the four third lead wires 43 constituting the third lead wire group are connected and fixed are each connected to terminals 723 (actually four terminals) of the catheter connection connector 72.

Here, terminals 721 and 722 of the catheter connector 72 are connected to a first ON/OFF switch 761 , and terminal 723 is directly connected to the electrocardiograph connector 73 without passing through the first ON/OFF switch 761 .
As a result, the cardiac potential information measured by the first DC electrode group 31G and the second DC electrode group 32G reaches the electrocardiograph connection connector 73 via the first ON/OFF switch 761, and the cardiac potential information measured by the base-end potential measurement electrode group 33G reaches the electrocardiograph connection connector 73 without passing through the first ON/OFF switch 761.

The electrocardiograph connector 73 is connected to an input terminal of the electrocardiograph 800 .
The external switch 74, which is an input means, comprises a main power switch 740 for starting up the power supply device 700, a mode changeover switch 741 for switching between a cardiac potential measurement mode and a defibrillation/impedance measurement mode, an applied energy setting switch 742 for setting the electrical energy to be applied during defibrillation, a charging switch 743 for storing a voltage determined based on the set electrical energy in the DC power supply section, an energy application preparation switch 744 for preparing to perform defibrillation (switching the relay), and an energy application execution switch 745 for applying electrical energy to perform defibrillation.
All of the input signals from these external switches 74 are sent to an arithmetic processing unit 75 .

The arithmetic processing unit 75 controls the DC power supply unit 71 , the first ON/OFF switch 761 and the second ON/OFF switch 762 based on the input of the external switch 74 .
This calculation processing unit 75 has an output circuit 751 for outputting a DC voltage from the DC power supply unit 71 to the electrodes of the defibrillation catheter 100 via a second ON/OFF switch 762, an IMP measurement circuit 752 for measuring the impedance (IMP) between the first DC electrode group 31G of the defibrillation catheter 100 or the first electrode 31 constituting it, and the second DC electrode group 32G or the second electrode 32 constituting it, an internal resistor 753 with a known resistance value used for operation confirmation (test), and a switching unit 754 for switching the connection destinations of each of the output circuit 751 and the IMP measurement circuit 752 between the internal resistor 753 and the second ON/OFF switch 762.

The output circuit 751 can apply a DC voltage to terminal 721 (ultimately, the first DC electrode group 31G of the defibrillation catheter 100) of the catheter connection connector 72 shown in Figure 7 and terminal 722 (ultimately, the second DC electrode group 32G of the defibrillation catheter 100) of the catheter connection connector 72 so that they have different polarities (when one electrode group is negative, the other electrode group is positive).

The IMP measurement circuit 752 makes it possible to measure the impedance between the first DC electrode group 31G and the second DC electrode group 32G of the defibrillation catheter 100, and the measured value of the impedance between the first DC electrode group 31G and the second DC electrode group 32G (between the electrode groups) is used to determine the target voltage to be stored in the DC power supply unit 71.

The first ON/OFF switch 761 is connected to the catheter connection connector 72 and also to the electrocardiograph connection connector 73 .
The second ON/OFF switch 762 is connected to the catheter connection connector 72 and also to the calculation processing unit 75 .

By turning the first ON/OFF switch 761 to "ON" and the second ON/OFF switch 762 to "OFF", cardiac potential information from the defibrillation catheter 100 can be input to the electrocardiograph 800 via the catheter connection connector 72, the first ON/OFF switch 761 and the electrocardiograph connection connector 73 (cardiac potential measurement mode).

In addition, by turning the first ON/OFF switch 761 "OFF" and the second ON/OFF switch 762 "ON" while the output circuit 751 and the second ON/OFF switch 762 are connected via the switching unit 754, voltages of different polarities can be applied from the DC power supply unit 71 to the first DC electrode group 31G and the second DC electrode group 32G of the defibrillation catheter 100 via the output circuit 751, the switching unit 754, the second ON/OFF switch 762 and the catheter connection connector 72 of the arithmetic processing unit 75 (defibrillation/impedance measurement mode).

In addition, when the IMP measurement circuit 752 and the second ON/OFF switch 762 are connected via the switching unit 754, the impedance between the first DC electrode group 31G and the second DC electrode group 32G of the defibrillation catheter 100 can be measured by turning the first ON/OFF switch 761 to "OFF" and the second ON/OFF switch 762 to "ON."

The switching between "ON" and "OFF" of the first ON/OFF switch 761 and the second ON/OFF switch 762 is controlled by the calculation processing unit 75 based on the input of the external switches 74, namely the mode changeover switch 741 and the energy application preparation switch 744.

The IMP measurement circuit 752 can measure the impedance between the first DC electrode group 31G and the second DC electrode group 32G (between the electrode groups) of the defibrillation catheter 100, and can also measure the impedance between the first electrode 31 constituting the first DC electrode group 31G and the second electrode 32 constituting the second DC electrode group 32G (between the electrodes).

Prior to performing defibrillation, the calculation processing unit 75 controls the switch group described below so that the impedance between one first electrode 31 and one second electrode 32 is measured by the IMP measurement circuit 752 for the eight first electrodes 31 (311 to 318 shown in Figures 15A to 15C) constituting the first DC electrode group 31G and the eight second electrodes 32 (321 to 328 shown in Figures 15A to 15C) constituting the second DC electrode group 32G (i.e., all constituent electrodes are measured).

Figures 15A to 15C show schematic circuit configurations for switching between measuring the impedance (between electrodes) between each of the first electrodes 311 to 318 constituting the first DC electrode group 31G and each of the second electrodes 321 to 328 constituting the second DC electrode group 32G; measuring the impedance (between electrode groups) between the first DC electrode group 31G and the second DC electrode group 32G; and applying a DC voltage to the first DC electrode group 31G and the second DC electrode group 32G (performing defibrillation).

15A to 15C, 789 is a changeover switch having a common contact to which ON/OFF switches 781 to 788 are connected, an output circuit 751 is connected to a first contact, and an IMP measuring circuit 752 is connected to a second contact.
Reference numeral 799 denotes a changeover switch having a common contact to which the ON/OFF switches 791 to 798 are connected, an output circuit 751 to a first contact, and an IMP measuring circuit 752 to a second contact.

781 to 788 are ON/OFF switches provided between each of the first electrodes 311 to 318 and the changeover switch 789. The ON/OFF switches 781 to 788 are connected to the base ends of the eight first lead wires whose tips are connected to each of the first electrodes 311 to 318, and each of the base ends of the first lead wires can be connected to the output circuit 751 or the IMP measurement circuit 752 via the changeover switch 789.

791 to 798 are ON/OFF switches provided between each of the second electrodes 321 to 328 and the changeover switch 799. The ON/OFF switches 791 to 798 are connected to the base ends of the eight second lead wires whose tips are connected to each of the second electrodes 321 to 328, and each of the base ends of the second lead wires can be connected to the output circuit 751 or the IMP measurement circuit 752 via the changeover switch 799.

The ON/OFF switches 781 to 788 and 791 to 798 constitute a group of switches in this embodiment.
The group of switches consisting of ON/OFF switches 781 to 788 and 791 to 798 , as well as the changeover switches 789 and 799 are disposed inside the power supply device 700 .

The switching between "ON" and "OFF" in the ON/OFF switches 781 to 788 and 791 to 798, and the switching between the "first contact" and "second contact" in the change-over switches 789 and 799 are controlled by the calculation processing unit 75.

15A, the second contact (IMP measuring circuit 752) is selected in the changeover switch 789 and the changeover switch 799, and only the switch 781 of the ON/OFF switches 781 to 788 is "ON", and only the switch 791 of the ON/OFF switches 791 to 798 is "ON". This makes it possible to measure the impedance between the first electrode 311 and the second electrode 321 (between the electrodes).

In this way, by turning only the switch designated 78X (X is an integer from 1 to 8) among switches 781 to 788 "ON" and by turning only the switch designated 79Y (Y is an integer from 1 to 8) among switches 791 to 798 "ON", it is possible to measure the impedance between the first electrode designated 31X and the second electrode designated 32Y.

In the above, by assuming that X=Y, i.e. by measuring the impedance between the first electrode 31k that is the kth electrode (k is an integer between 1 and 8) from the tip of the first DC electrode group 31G and the second electrode 32k that is the kth electrode from the tip of the second DC electrode group 32G eight times, all of the first electrodes 311-318 and the second electrodes 321-328 can be selected as the measurement targets.

15B, the second contact (IMP measurement circuit 752) is selected in the changeover switch 789 and the changeover switch 799, and all of the switches 781 to 788 and the switches 791 to 798 are "ON." This makes it possible to measure the impedance between the first DC electrode group 31G and the second DC electrode group 32G (between the electrode groups).

15C, the first contact (output circuit 751) is selected in the changeover switch 789 and the changeover switch 799, and all of the switches 781-788 and the switches 791-798 are "ON." This makes it possible to apply voltages of different polarities to the first DC electrode group 31G and the second DC electrode group 32G via the output circuit 751, thereby performing defibrillation.

The electrocardiogram input connector 77 is connected to the calculation processing unit 75 and also to an output terminal of the electrocardiograph 800 .
This electrocardiogram input connector 77 allows cardiac potential information output from the electrocardiograph 800 (usually a portion of the cardiac potential information input to the electrocardiograph 800) to be input to the calculation processing unit 75, and the calculation processing unit 75 can control the DC power supply unit 71, the first ON/OFF switch 761 and the second ON/OFF switch 762 based on this cardiac potential information.

The electrocardiograph 800 (input terminal) constituting the catheter system of this embodiment is connected to the electrocardiograph connection connector 73 of the power supply unit 700, and cardiac potential information measured by the defibrillation catheter 100 (electrodes constituting the first DC electrode group 31G, the second DC electrode group 32G and the base-end potential measurement electrode group 33G) is input from the electrocardiograph connection connector 73 to the electrocardiograph 800.

Moreover, the electrocardiograph 800 (the other input terminal) is also connected to a cardiac potential measuring means 900 , and cardiac potential information measured by the cardiac potential measuring means 900 is also input to the electrocardiograph 800 .
Here, the cardiac potential measuring means 900 can include an electrode pad that is attached to the surface of the patient's body to measure a 12-lead electrocardiogram, and an electrode catheter (an electrode catheter different from the defibrillation catheter 100) that is inserted into the patient's heart.

The electrocardiograph 800 (output terminal) is connected to the electrocardiogram input connector 77 of the power supply unit 700, and a portion of the cardiac potential information input to the electrocardiograph 800 (cardiac potential information from the defibrillation catheter 100 and cardiac potential information from the cardiac potential measuring means 900) can be sent from the electrocardiogram input connector 77 to the calculation processing unit 75.

The defibrillation catheter 100 in this embodiment can be used as an electrode catheter for measuring cardiac potentials when defibrillation treatment is not required.

The cardiac potential measured by the electrodes constituting the first DC electrode group 31G and/or the second DC electrode group 32G of the defibrillation catheter 100 is input to the electrocardiograph 800 via the catheter connection connector 72, the first ON/OFF switch 761, and the electrocardiograph connection connector 73.
In addition, the cardiac potential measured by the electrodes that make up the base-end potential measurement electrode group 33G of the defibrillation catheter 100 is input from the catheter connection connector 72 to the electrocardiograph 800 directly via the electrocardiograph connection connector 73 without passing through the first ON/OFF switch 761.

The cardiac potential information (cardiac potential waveform) from the defibrillation catheter 100 is displayed on a monitor (not shown) of the electrocardiograph 800 .
In addition, a portion of the cardiac potential information from the defibrillation catheter 100 (for example, the potential difference between the first electrodes 31 (the first and second electrodes) that constitute the first DC electrode group 31G) can be input from the electrocardiograph 800 to the calculation processing unit 75 via the electrocardiogram input connector 77.

As described above, when defibrillation treatment is not required during cardiac catheterization, the defibrillation catheter 100 can be used as an electrode catheter for measuring cardiac potentials (cardiac potential measurement mode).
If atrial fibrillation occurs during cardiac catheterization, defibrillation treatment can be immediately performed using the defibrillation catheter 100 that has been used as an electrode catheter (defibrillation/impedance measurement mode). As a result, it is possible to eliminate the need to insert a new catheter for defibrillation when atrial fibrillation occurs.

Below, an example of defibrillation treatment using the intracardiac defibrillation catheter system of this embodiment is described with reference to the flowchart shown in Figure 8.

(1) Turn on the main power switch 740 of the power supply unit 700 (STEP 1).

(2) The defibrillation catheter 100 is connected to the power supply device 700 (catheter connection connector 72) (STEP 2).
Here, the first DC electrode group 31G of the defibrillation catheter 100 is positioned in the coronary sinus (CS), the second DC electrode group 32G is positioned in the right atrium (RA), and the base-end potential measurement electrode group 33G is positioned in the superior vena cava (SVC).

(3) When the main power switch 740 is turned on, the mode (initial mode) of the power supply device 700 is the "cardiac potential measurement mode" (STEP 3, FIG. 9).
As shown in FIG. 9, the first ON/OFF switch 761 is in the "ON" state, and the second ON/OFF switch 762 is in the "OFF" state.
As a result, cardiac potential information measured by the constituent electrodes of the first DC electrode group 31G and/or the second DC electrode group 32G is input to the electrocardiograph 800 via the catheter connection connector 72, the first ON/OFF switch 761, and the electrocardiograph connection connector 73. Moreover, cardiac potential information measured by the constituent electrodes of the base-end potential measurement electrode group 33G is input to the electrocardiograph 800 via the catheter connection connector 72 and the electrocardiograph connection connector 73. The cardiac potential information input to the electrocardiograph 800 is input to the calculation processing unit 75 via the electrocardiogram input connector 77.
In addition, cardiac potential information (12-lead electrocardiogram) measured by the cardiac potential measuring means 900 (electrode pads attached to the body surface) is also input to the electrocardiograph 800, and the cardiac potential information from the cardiac potential measuring means 900 is also input to the calculation processing unit 75 via the electrocardiogram input connector 77.
In the calculation processing unit 75 shown in FIG. 9, the IMP measuring circuit 752 and the internal resistor 753 are connected via a switching unit 754, and at this stage, the resistance value of the internal resistor 753 can be measured by the IMP measuring circuit 752 to confirm (test) whether it matches a known resistance value.

(4) Turn on mode change switch 741 (STEP 4).

(5) When the mode change switch 741 is turned on, the power supply device 700 goes into the "defibrillation/impedance measurement mode" (STEP 5, FIG. 10).
As shown in FIG. 10, the first ON/OFF switch 761 is in the "OFF" state, and the second ON/OFF switch 762 is in the "ON" state.
In the arithmetic processing unit 75 shown in FIG. 10, the IMP measuring circuit 752 and the second ON/OFF switch 762 are connected via the switching unit 754 .
When the first ON/OFF switch 761 is turned to the "OFF" state, the path from the catheter connection connector 72 via the first ON/OFF switch 761 to the electrocardiograph connection connector 73 is blocked, so that cardiac potential information from the constituent electrodes of the first DC electrode group 31G and the second DC electrode group 32G of the defibrillation catheter 100 cannot be input to the electrocardiograph 800 (and therefore this cardiac potential information cannot be sent to the arithmetic processing unit 75). However, cardiac potential information from the constituent electrodes of the base-end potential measuring electrode group 33G that does not pass through the first ON/OFF switch 761 is input to the electrocardiograph 800.

(6) The IMP measurement circuit 752 of the calculation processing unit 75 sequentially measures the impedance (between the electrodes) between each of the first electrodes 311 to 318 constituting the first DC electrode group 31G of the defibrillation catheter 100 and each of the second electrodes 321 to 328 constituting the second DC electrode group 32G (STEP 6, Figures 10 and 15A).

15A, the second contact (IMP measuring circuit 752) is selected in the changeover switches 789 and 799, and only the switch 781 of the switches 781 to 788 is turned "ON," and only the switch 791 of the switches 791 to 798 is turned "ON." This causes the impedance between the first electrode 311 and the second electrode 321 to be measured.
Next, switch 781 is turned “OFF”, switch 782 is turned “ON”, switch 791 is turned “OFF”, and switch 792 is turned “ON”, thereby measuring the impedance between first electrode 312 and second electrode 322.
Next, switch 782 is turned “OFF”, switch 783 is turned “ON”, switch 792 is turned “OFF”, and switch 793 is turned “ON”, thereby measuring the impedance between first electrode 313 and second electrode 323 .
Similarly, by switching the pairs of switches (78X, 79X) to "ON", the impedance between the first electrode 314 and the second electrode 324, between the first electrode 315 and the second electrode 325, between the first electrode 316 and the second electrode 326, between the first electrode 317 and the second electrode 327, and between the first electrode 318 and the second electrode 328 is measured.
The time required for measuring the inter-electrode impedance eight times as described above is approximately several seconds.

(7) Determine whether all of the eight impedances measured in STEP 6 are equal to or less than a predetermined value. If all of the impedances are equal to or less than the predetermined value, proceed to STEP 8. If at least one of the impedances exceeds the predetermined value, interrupt or discontinue defibrillation therapy and return to STEP 2 (STEP 7).
If at least one impedance exceeds a predetermined value, the calculation processor 75 determines that some of the lead wires are disconnected, and does not send a control signal for applying a DC voltage to the first DC electrode group 31G and the second DC electrode group 32G to the DC power supply unit 71. As a result, even if the operator performs a subsequent operation to perform defibrillation (operations in STEPs 10, 11, 13, and 17 described later), the operation is invalid.
Here, the "predetermined value" that serves as a criterion for determining whether or not there is a break is, for example, 500 Ω.
The fact that at least one impedance has exceeded a predetermined value is displayed on a display means (not shown) provided in the power supply device 700, or an operator is notified by an alarm, etc. This allows the operator to interrupt or discontinue defibrillation therapy to replace the defibrillation catheter 100, etc.

(8) The IMP measurement circuit 752 of the calculation processing unit 75 measures the impedance between the first DC electrode group 31G and the second DC electrode group 32G (between the electrode groups) of the defibrillation catheter 100 (STEP 8, Figures 10 and 15B).

15B, the second contact (IMP measurement circuit 752) is selected in the changeover switch 789 and the changeover switch 799, and all of the switches 781 to 788 and the switches 791 to 798 are turned "ON." This makes it possible to measure the impedance between the first DC electrode group 31G and the second DC electrode group 32G (between the electrode groups).
The time required to measure the impedance between the electrode groups is approximately one second.

(9) The mode of the power supply device 700 returns to the “cardiac potential measuring mode” (STEP 9, FIG. 11).
As shown in FIG. 11, the first ON/OFF switch 761 is in the "ON" state, and the second ON/OFF switch 762 is in the "OFF" state.
In addition, in the calculation processing unit 75 shown in FIG. 11, the output circuit 751 and the internal resistance 753 are connected via the switching unit 754. At this stage, it is possible to apply a DC voltage to the internal resistance 753, and it is possible to confirm (test) whether or not the set electrical energy can be applied to the internal resistance 753.

(10) The applied energy setting switch 742 is turned on to set the applied energy during defibrillation (STEP 10).
According to the electrode device 700 of this embodiment, the applied energy can be set from 1 J to 30 J in 1 J increments.

(11) Turn on the charging switch 743 (STEP 11).

(12) A target voltage determined based on the impedance between the electrode groups measured in STEP 8 and the electrical energy set in STEP 10 is stored in the DC power supply unit (STEP 12).

(13) Turn on the energy application preparation switch 744 (STEP 13).

(14) When the energy application preparation switch 744 is input, a control signal is received from the calculation processing unit 75, and the first ON/OFF switch 761 maintains the “ON” state, and the second ON/OFF switch 762 switches from “OFF” to “ON” (STEP 14, FIG. 12).
In the arithmetic processing unit 75 shown in FIG. 12, the output circuit 751 and the second ON/OFF switch 762 are connected via the switching unit 754 .

(15) Visually check the electrocardiogram related to the cardiac potential information from the constituent electrodes of the first DC electrode group 31G and/or the second DC electrode group 32G of the defibrillation catheter 100 (STEP 15). At this time, the electrocardiogram related to the cardiac potential information from the constituent electrodes of the base-end potential measurement electrode group 33G and/or the cardiac potential information by the cardiac potential measurement means 900 may also be checked.

(16) Determine whether the drift (baseline fluctuation) in the electrocardiogram caused by mode switching, etc. has subsided. If it has subsided, proceed to STEP 17; if it has not subsided, return to STEP 15 (STEP 16).

(17) Turn on the energy application execution switch 745 (STEP 17).

(18) When the energy application execution switch 745 is input, the second ON/OFF switch 762 receives a control signal from the calculation processing unit 75, maintains the "ON" state, and the first ON/OFF switch 761 switches from "ON" to "OFF", immediately blocking the path from the catheter connection connector 72 to the electrocardiograph connection connector 73 (STEP 18, FIG. 13). As a result, the mode of the power supply device 700 becomes the "defibrillation/impedance measurement mode", and no DC voltage is applied to the electrocardiograph 800.

(19) Upon receiving a control signal from the calculation processing unit 75, the DC power supply unit 71 applies DC voltages of different polarities to the first DC electrode group 31G and the second DC electrode group 32G of the defibrillation catheter 100 via the output circuit 751 and switching unit 754 of the calculation processing unit 75, the second ON/OFF switch 762, and the catheter connection connector 72 (STEP 19, Figures 14 and 15C).

(20) After the application of voltage from the DC power supply unit 71 stops, the mode of the power supply unit 700 returns to the "cardiac potential measurement mode", and cardiac potential information from the constituent electrodes of the first DC electrode group 31G and the second DC electrode group 32G of the defibrillation catheter 100 is input to the electrocardiograph 800 (STEP 20).

(21) Observe the cardiac potential information (electrocardiogram) from the constituent electrodes of the defibrillation catheter 100 (the constituent electrodes of the first DC electrode group 31G, the second DC electrode group 32G, and the base-end potential measurement electrode group 33G) displayed on the monitor of the electrocardiograph 800, as well as the cardiac potential information (12-lead electrocardiogram) from the cardiac potential measurement means 900. If the results are “normal,” end the process. If the results are “not normal (atrial fibrillation has not subsided),” return to STEP 4 (STEP 21).

According to the catheter system of this embodiment, by measuring the impedance between the electrodes eight times, it is possible to check for breaks in the 16 lead wires (first lead wire 41 and second lead wire 42) connected to each of the first electrodes 311-318 and the second electrodes 321-328.

In addition, since the distance between the first electrode 31 and the second electrode 32 selected for measuring the impedance is the same for all eight measurements, the influence (error) on the measurement value due to differences in the distance between the electrodes can be eliminated.
Furthermore, if at least one impedance exceeds a predetermined value, application of DC voltage (defibrillation) is not performed, thereby reliably avoiding tissue damage caused by lead wire breakage.

In addition, by connecting the IMP measuring circuit 752 and the internal resistance 753 via the switching unit 754, the resistance value of the internal resistance 753 can be measured by the IMP measuring circuit 752, and the operating status of the impedance measurement system including the IMP measuring circuit 752 can be confirmed.

In addition, by connecting the output circuit 751 and the internal resistance 753 via the switching unit 754, the operating state of the DC voltage output system including the output circuit 751 can be confirmed by applying electrical energy to the internal resistance 753 via the output circuit 751.

Second Embodiment
The intracardiac defibrillation catheter system of this embodiment differs from that of the first embodiment in the circuit configuration for switching between measuring the inter-electrode impedance, measuring the inter-electrode group impedance, and applying a DC voltage (performing defibrillation), but the other configurations are similar to those of the first embodiment.

Figures 16A to 16D show schematic circuit configurations for switching between measuring the impedance (inter-electrode impedance) between two first electrodes 31 selected from the first DC electrode group 31G; measuring the impedance (inter-electrode impedance) between two second electrodes 32 selected from the second DC electrode group 32G; measuring the impedance (inter-electrode impedance) between the first DC electrode group 31G and the second DC electrode group 32G; and applying a DC voltage to the first DC electrode group 31G and the second DC electrode group 32G (performing defibrillation).

In Figures 16A to 16D, the same components as those shown in Figures 15A to 15C are designated by the same reference numerals.
16A to 16D, 7894 denotes a changeover switch having a common contact connected to switch 787, a first contact connected to changeover switch 789, and a second contact connected to changeover switch 799.
Reference numeral 7893 denotes a changeover switch having a common contact connected to the switch 785, a first contact connected to the changeover switch 789, and a second contact connected to the changeover switch 7894.
Reference numeral 7892 denotes a changeover switch having a common contact connected to the switch 783, a first contact connected to the changeover switch 789, and a second contact connected to the changeover switch 7893.
Reference numeral 7891 denotes a changeover switch having a common contact connected to the switch 781, a first contact connected to the changeover switch 789, and a second contact connected to the changeover switch 7892.
Reference numeral 7994 denotes a changeover switch having a common contact connected to the switch 797, a first contact connected to the changeover switch 799, and a second contact connected to the changeover switch 789.
Reference numeral 7993 denotes a changeover switch having a common contact connected to switch 795, a first contact connected to changeover switch 799, and a second contact connected to changeover switch 7994.
Reference numeral 7992 denotes a changeover switch having a common contact connected to switch 793, a first contact connected to changeover switch 799, and a second contact connected to changeover switch 7993.
Reference numeral 7991 denotes a changeover switch having a common contact connected to the switch 791, a first contact connected to the changeover switch 799, and a second contact connected to the changeover switch 7992.
The changeover switches 7891 to 7894 and the changeover switches 7991 to 7994 are disposed inside the power supply device 700 .

In FIG. 16A, the second contacts (IMP measuring circuit 752) are selected in the changeover switches 789 and 799, and the second contacts are selected in the changeover switches 7891 to 7894 and 7991 to 7994.
Moreover, among the ON/OFF switches 781 to 788, only the switches 781 and 782 are "ON", and all of the ON/OFF switches 791 to 798 are "OFF".
This makes it possible to measure the impedance between adjacent first electrodes 311 and 312.

From this state, by turning switches 781 and 782 "OFF" and turning only switches 783 and 784 "ON", it becomes possible to measure the impedance between first electrode 313 and first electrode 314.
From this state, by turning switches 783 and 784 "OFF" and turning only switches 785 and 786 "ON", it becomes possible to measure the impedance between adjacent first electrodes 315 and 316.
From this state, by turning switches 785 and 786 "OFF" and turning only switches 787 and 788 "ON", it becomes possible to measure the impedance between adjacent first electrodes 317 and 318.

In FIG. 16B, the second contacts (IMP measuring circuit 752) are selected in the changeover switches 789 and 799, and the second contacts are selected in the changeover switches 7891 to 7894 and the changeover switches 7991 to 7994.
Moreover, all of the ON/OFF switches 781 to 788 are "OFF", and among the ON/OFF switches 791 to 798, only the switches 791 and 792 are "ON".
This makes it possible to measure the impedance between the adjacent second electrodes 321 and 322 .

From this state, by turning switches 791 and 792 "OFF" and turning only switches 793 and 794 "ON", it becomes possible to measure the impedance between second electrode 323 and second electrode 324.
From this state, by turning switches 793 and 794 "OFF" and turning only switches 795 and 796 "ON", it becomes possible to measure the impedance between adjacent second electrodes 325 and 326.
From this state, by turning switches 795 and 796 "OFF" and turning only switches 797 and 798 "ON", it becomes possible to measure the impedance between adjacent second electrodes 327 and 328.

In FIG. 16C, the second contacts (IMP measuring circuit 752) are selected in the changeover switches 789 and 799, and the first contacts are selected in the changeover switches 7891 to 7894 and 7991 to 7994.
Additionally, all of the switches 781 to 788 and the switches 791 to 798 are “ON.” This makes it possible to measure the impedance between the first DC electrode group 31G and the second DC electrode group 32G (between the electrode groups).

In FIG. 16D, the first contact (output circuit 751) is selected in the changeover switches 789 and 799, and the first contact is selected in the changeover switches 7891 to 7894 and 7991 to 7994.
Additionally, all of the switches 781 to 788 and the switches 791 to 798 are “ON.” This makes it possible to apply voltages of different polarities to the first DC electrode group 31G and the second DC electrode group 32G via the output circuit 751, thereby performing defibrillation.

According to the catheter system of this embodiment, by measuring the impedance between the electrodes eight times (four times for the first electrode 31 and four times for the second electrode), it is possible to check for breaks in the 16 lead wires (first lead wire 41 and second lead wire 42) connected to each of the first electrode 31 (311-318) and second electrode 32 (321-328).

In addition, since the distance between the first electrode 31 and the second electrode 32 selected to measure the impedance is the same and the shortest in all eight measurements, it is possible to eliminate the influence (error) on the measurement value caused by the distance between the electrodes being different or excessively large.

In this embodiment, the impedance was measured between the same DC electrode groups (between adjacent first electrodes and between adjacent second electrodes). However, according to the circuit configuration shown in FIGS. 16A to 16D, it is also possible to measure the impedance between non-adjacent first electrodes (e.g., first electrode 311 and first electrode 314), between non-adjacent second electrodes (e.g., second electrode 321 and second electrode 324), and between first electrode 31 and second electrode 32.

Although the embodiments of the present invention have been described above, the catheter system of the present invention is not limited to these and various modifications are possible.
For example, the ON/OFF switches 781 to 788 and 791 to 798 shown in FIGS. 15A to 15C and 16A to 16D are each a one-circuit, two-contact changeover switch, but a one-circuit, one-contact switch may be used instead.

The catheter system of the present invention is not limited to an intracardiac defibrillation catheter system, but may be a catheter system including an electrode catheter having multiple electrodes attached thereto and a power supply device that applies energy to these electrodes.

100 Defibrillation catheter 10 Multi-lumen tube 11 First lumen 12 Second lumen 13 Third lumen 14 Fourth lumen 15 Fluororesin layer 16 Inner (core) part 17 Outer (shell) part 18 Stainless steel wire 20 Handle 21 Handle body 22 Knob 24 Strain relief 26 First insulating tube 27 Second insulating tube 28 Third insulating tube 31G First DC electrode group 31 (311-318) First electrode 32G Second DC electrode group 32 (321-328) Second electrode 33G Base end potential measurement electrode group 33 Third electrode 35 Distal tip 41G First lead wire group 41 First lead wire 42G Second lead wire group 42 Second lead wire 43G Third lead wire group 43 Lead wire 50 Defibrillation catheter connector 51, 52, 53 Pin terminal 61 First protective tube 62 Second protective tube 65 Pull wire 700 Power supply device 71 DC power supply unit 72 Catheter connection connector 721, 722, 723 Terminal 73 Electrocardiograph connection connector 74 External switch (input means)
740 Main power switch 741 Mode changeover switch 742 Applied energy setting switch 743 Charging switch 744 Energy application preparation switch 745 Energy application execution switch (discharge switch)
75 Arithmetic processing unit 751 Output circuit 752 IMP measuring circuit 753 Internal resistance 754 Switching unit 761 First ON/OFF switch 762 Second ON/OFF switch 77 Electrocardiogram input connector 781 to 788 ON/OFF switch 789 Changeover switch 791 to 798 ON/OFF switch 799 Changeover switch 7891 to 7894 Changeover switches 7991 to 7994 Changeover switches 800 Electrocardiograph 900 Cardiac potential measuring means

Claims (15)

A catheter system including a defibrillation catheter that is inserted into a cardiac cavity to perform defibrillation, and a power supply device that applies a DC voltage to an electrode of the defibrillation catheter,
the defibrillation catheter comprises an insulating tube member, a first DC electrode group consisting of a plurality of first electrodes attached to a distal end region of the tube member, a second DC electrode group consisting of a plurality of second electrodes attached to the distal end region of the tube member at a distance from the first DC electrode group to the proximal end side, a first lead wire group consisting of a plurality of first lead wires connected to respective tips of the first electrodes constituting the first DC electrode group, and a second lead wire group consisting of a plurality of second lead wires connected to respective tips of the second electrodes constituting the second DC electrode group;
The power supply device includes a DC power supply unit having a capacitor, and an arithmetic processing unit that controls the DC power supply unit based on an external input and has an output circuit for outputting a DC voltage from the DC power supply unit,
When defibrillation is performed by the defibrillation catheter, voltages of different polarities are applied to the first DC electrode group and the second DC electrode group of the defibrillation catheter from the DC power supply unit via the output circuit of the arithmetic processing unit,
an impedance measuring section for measuring an impedance between a first electrode selected from the first DC electrode group and a second electrode selected from the second DC electrode group, the impedance being measured for all of the first electrodes constituting the first DC electrode group and all of the second electrodes constituting the second DC electrode group, prior to performing defibrillation; The arithmetic processing unit of the power supply device has an impedance measurement circuit capable of measuring an impedance between the first DC electrode group or the first electrodes constituting the first DC electrode group and the second DC electrode group or the second electrodes constituting the second DC electrode group,
the power supply device has a switch group including a plurality of switches connected to a base end of each of the first lead wires or a base end of each of the second lead wires, and capable of connecting each of the base ends to the output circuit or the impedance measurement circuit;
2. The intracardiac defibrillation catheter system according to claim 1, wherein the calculation processing unit of the power supply device controls the switch group so that, prior to performing defibrillation, impedance between one first electrode selected from the first DC electrode group and one second electrode selected from the second DC electrode group is measured by the impedance measurement circuit for all of the first electrodes constituting the first DC electrode group and all of the second electrodes constituting the second DC electrode group. The first DC electrode group is composed of n (n is an integer of 2 or more) first electrodes, and the second DC electrode group is composed of n second electrodes,
The intracardiac defibrillation catheter system according to claim 1 or 2, characterized in that the calculation processing unit of the power supply device controls so that the impedance between a first electrode that is k-th (k is an integer from 1 to n) from the tip of the first DC electrode group and a second electrode that is k-th from the tip of the second DC electrode group is measured n times. An intracardiac defibrillation catheter system as described in any one of claims 1 to 3, characterized in that the calculation processing unit of the power supply device controls the DC power supply unit so that defibrillation can be performed only when all of the measured impedances are below a predetermined value. The power supply device is provided with a display means,
The intracardiac defibrillation catheter system according to any one of claims 1 to 3, characterized in that, when an impedance exceeding a predetermined value is measured, the calculation processing unit of the power supply device controls the display means to display a combination of the first electrode and the second electrode for which the impedance is measured. The intracardiac defibrillation catheter system according to claim 5, characterized in that the calculation processing unit of the power supply device identifies the first electrode and/or the second electrode that caused the impedance measured to exceed a predetermined value, and controls the display means to display the electrode. An intracardiac defibrillation catheter system as described in any one of claims 1 to 6, characterized in that the calculation processing unit of the power supply device controls so that after defibrillation is performed, the impedance between one first electrode selected from the first DC electrode group and one second electrode selected from the second DC electrode group is measured again for all of the first electrodes constituting the first DC electrode group and all of the second electrodes constituting the second DC electrode group. The intracardiac defibrillation catheter system of claim 7, characterized in that the calculation processing unit of the power supply device controls so that measurement of impedance between the first electrode and the second electrode is started immediately after defibrillation is performed. An intracardiac defibrillation catheter system as described in any one of claims 1 to 8, characterized in that the calculation processing unit of the power supply device further controls so that the impedance between the first DC electrode group and the second DC electrode group is measured. An intracardiac defibrillation catheter system further comprising an electrocardiograph,
the power supply device comprises the DC power supply unit, an external switch serving as an input means, the arithmetic processing unit, a catheter connection connector electrically connected to each of the first DC electrode group and the second DC electrode group of the defibrillation catheter, an electrocardiograph connection connector connected to an input terminal of the electrocardiograph, and a branch connection unit connected to the catheter connection connector and connected to the electrocardiograph connection connector and the arithmetic processing unit;
When measuring an intracardiac potential using the electrodes constituting the first DC electrode group and/or the second DC electrode group of the defibrillation catheter, cardiac potential information from the defibrillation catheter is input to the electrocardiograph via the catheter connection connector, the branch connection section, and the electrocardiograph connection connector,
When defibrillation is performed by the defibrillation catheter, voltages of different polarities are applied to the first DC electrode group and the second DC electrode group of the defibrillation catheter from the DC power supply unit via the output circuit of the arithmetic processing unit, the branch connection unit, and the catheter connection connector,
3. The intracardiac defibrillation catheter system according to claim 2, wherein, when measuring the impedance between the first DC electrode group and the second DC electrode group of the defibrillation catheter, or the impedance between the first electrode and the second electrode, the measured impedance information is input to the arithmetic processing unit via the catheter connection connector, the branch connection unit, and an impedance measuring circuit of the arithmetic processing unit. A catheter system including a defibrillation catheter that is inserted into a cardiac cavity to perform defibrillation, and a power supply device that applies a DC voltage to an electrode of the defibrillation catheter,
the defibrillation catheter comprises an insulating tube member, a first DC electrode group consisting of a plurality of first electrodes attached to a distal end region of the tube member, a second DC electrode group consisting of a plurality of second electrodes attached to the distal end region of the tube member at a distance from the first DC electrode group to the proximal end side, a first lead wire group consisting of a plurality of first lead wires connected to respective tips of the first electrodes constituting the first DC electrode group, and a second lead wire group consisting of a plurality of second lead wires connected to respective tips of the second electrodes constituting the second DC electrode group;
the power supply device comprises a DC power supply unit having a capacitor and an arithmetic processing unit, the arithmetic processing unit controls the DC power supply unit based on an external input, and has an output circuit for a DC voltage from the DC power supply unit, and an impedance measurement circuit capable of measuring an impedance between the first DC electrode group and the second DC electrode group and an impedance between electrodes constituting the first DC electrode group or the second DC electrode group;
When defibrillation is performed by the defibrillation catheter, voltages of different polarities are applied to the first DC electrode group and the second DC electrode group of the defibrillation catheter from the DC power supply unit via the output circuit of the arithmetic processing unit,
an impedance measuring circuit for measuring an impedance between two electrodes selected from the first DC electrode group and the second DC electrode group for all of the first electrodes constituting the first DC electrode group and all of the second electrodes constituting the second DC electrode group, prior to performing defibrillation; The intracardiac defibrillation catheter system of claim 11, characterized in that the two electrodes selected from the first DC electrode group and the second DC electrode group are adjacent electrodes to each other. An intracardiac defibrillation catheter system as described in claim 2 or 11, characterized in that a part of the calculation processing unit including the impedance measurement circuit is arranged outside the power supply device. A catheter system comprising an electrode catheter for performing ablation and a power supply device for applying energy to an electrode of the electrode catheter,
The electrode catheter comprises an insulating tube member, an electrode group consisting of a plurality of electrodes attached to a distal end region of the tube member, and a lead wire group consisting of a plurality of lead wires whose distal ends are connected to the electrodes constituting the electrode group,
the power supply device includes a power supply unit and an arithmetic processing unit that controls the power supply unit based on an external input, the arithmetic processing unit having an output circuit for energy from the power supply unit and an impedance measurement circuit capable of measuring impedance between electrodes that constitute the electrode group,
When ablation is performed by the electrode catheter, energy is applied to the electrodes constituting the electrode group from the power supply unit via the output circuit of the arithmetic processing unit,
A catheter system characterized in that the calculation processing unit of the power supply device controls so that, prior to performing ablation, the impedance between two electrodes selected from all of the electrodes that constitute the electrode group is measured by the impedance measurement circuit. 15. A catheter system as claimed in claim 14 for performing pulsed field ablation.

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