JP7482283B2 - Intracardiac Defibrillation System - Google Patents

Description

This disclosure relates to an intracardiac defibrillation system.

If fibrillation occurs during surgery using a cardiac catheter, electrical defibrillation must be performed. Patent Document 1 describes an intracardiac defibrillation catheter system that includes a defibrillation catheter that is inserted into the cardiac cavity to perform defibrillation, and a power supply device that applies a DC voltage to the electrodes of the defibrillation catheter. The defibrillation catheter has a first electrode group consisting of multiple ring-shaped electrodes for applying a voltage of the same polarity, and a second electrode group consisting of multiple ring-shaped electrodes for applying a voltage of the opposite polarity to the first electrode group.

JP 2010-220778 A

In the intracardiac defibrillation catheter system described in Patent Document 1, the first electrode group and the second electrode group are attached to the outer periphery of the same tube member at a distance from each other. Therefore, since the distance between the first electrode group and the second electrode group on the tube member is constant, it is difficult to place the first electrode group and the second electrode group at the desired position in the cardiac cavity. Therefore, it may not be possible to place the first electrode group and the second electrode group in an appropriate position for the area where the myocardium is spasming. In such a case, it is necessary to set the defibrillation energy high in order to electrically reset the spasming area, which may reduce the defibrillation efficiency.

This disclosure provides an intracardiac defibrillation system that can improve defibrillation efficiency.

An intracardiac defibrillation system according to one aspect of the present disclosure includes a first defibrillation catheter for performing defibrillation in a cardiac chamber, the first defibrillation catheter having a first electrode group including a plurality of first electrodes, a second defibrillation catheter for performing defibrillation in a cardiac chamber, the second defibrillation catheter having a second electrode group including a plurality of second electrodes, a first connector for connecting the first defibrillation catheter, a second connector for connecting the second defibrillation catheter, and a defibrillation device having a power supply circuit that supplies voltage. The defibrillation device applies voltages of the same polarity to the plurality of first electrodes and applies voltages of the same polarity to the plurality of second electrodes.

In this intracardiac defibrillation system, the first defibrillation catheter has a first electrode group, and the second defibrillation catheter has a second electrode group. In this way, the first electrode group and the second electrode group are included in different defibrillation catheters, which improves the degree of freedom in placement of the first electrode group and the second electrode group. Therefore, the first electrode group and the second electrode group can be placed in a position close to the site where the myocardium is spasming. This allows defibrillation energy to be applied efficiently to the site where the myocardium is spasming. As a result, there is no need to set the defibrillation energy higher than necessary, which makes it possible to improve defibrillation efficiency.

In some embodiments, the defibrillator may apply a voltage of a different polarity to the second electrodes than the polarity of the voltage applied to the first electrodes. With this configuration, defibrillation energy can be applied between the first and second electrode groups.

In some embodiments, the intracardiac defibrillation system may further include a return electrode plate for performing defibrillation on the body surface. The defibrillator may further include a third connector for connecting the return electrode plate. The defibrillator may apply a voltage to the return electrode plate having a polarity different from the polarity of the voltage applied to the first electrodes or the second electrodes. With this configuration, defibrillation energy can be applied between the first group of electrodes or the second group of electrodes and the return electrode plate.

In some embodiments, the defibrillator may further include a switching circuit that can selectively switch between the first member of the first electrode group, the second electrode group, and the counter electrode plate, which is connected to the first terminal of the power supply circuit, and the second member of the first electrode group, which is connected to the second terminal of the power supply circuit. In this case, defibrillation can be performed using a combination selected from the first electrode group, the second electrode group, and the counter electrode plate. Therefore, an appropriate combination can be selected depending on the location where fibrillation has occurred, which makes it possible to improve defibrillation efficiency.

In some embodiments, the defibrillator may further include a measuring device that measures the resistance of the path through which the voltage is supplied. The switching circuit may selectively connect the first member and the second member to either the power supply circuit or the measuring device. With this configuration, a combination selected from the first electrode group, the second electrode group, and the return electrode plate is selectively connected to the power supply circuit and the measuring device. Therefore, the defibrillator can be made smaller than in a configuration in which a path for supplying voltage and a path for measuring resistance are provided separately.

In some embodiments, the intracardiac defibrillation system may further include an electrocardiograph. The first defibrillation catheter may further include a third electrode group including a plurality of third electrodes, and the second defibrillation catheter may further include a fourth electrode group including a plurality of fourth electrodes. The electrocardiograph may measure the potentials of the plurality of third electrodes and the potentials of the plurality of fourth electrodes. With this configuration, intracardiac potentials can be measured without using an electrophysiological testing catheter.

In some embodiments, the defibrillator may further include a measuring device that measures the resistance of the path through which the voltage is supplied, and an arithmetic processing unit that controls the power supply circuit. The arithmetic processing unit may apply a voltage to the power supply circuit when the resistance is within an appropriate range. When the resistance of the path through which the voltage is supplied is outside the appropriate range, it is considered that the electrode to which the voltage is applied is not properly placed. In order to perform defibrillation in this state, it is necessary to increase the defibrillation energy. According to the above configuration, when the resistance of the path through which the voltage is supplied is within the appropriate range, a voltage is applied, so there is no need to excessively increase the defibrillation energy. As a result, the defibrillation efficiency can be improved.

In some embodiments, the processor may apply a voltage to the power supply circuit in synchronization with a peak of the intracardiac potential. In this configuration, the voltage is applied in synchronization with a peak of the intracardiac potential, thereby preventing the induction of ventricular fibrillation.

In some embodiments, the first defibrillation catheter may further include a tubular member. Each of the multiple first electrodes may be provided on the outer circumferential surface of the tubular member, and the multiple first electrodes may be arranged in the axial direction of the tubular member. With this configuration, the flexibility and pliability of the first defibrillation catheter can be increased compared to a configuration in which the multiple first electrodes are integrated. Therefore, it is possible to improve the operability of the first defibrillation catheter.

In some embodiments, the first defibrillation catheter may further include a distal tip provided at the distal end of the tubular member, a pull wire disposed within the tubular member and having one end fixed to the distal tip at a position eccentric to the central axis of the tubular member, and an operating unit for advancing and retracting the pull wire in the axial direction. According to this configuration, one end of the pull wire is fixed to the distal tip at a position eccentric to the central axis of the tubular member, so that by advancing and retracting the pull wire with the operating unit, a force is applied to the distal tip at a position eccentric to the central axis. This allows the distal end of the tubular member to be deflected. As a result, it is possible to improve the operability of the first defibrillation catheter.

In some embodiments, the first defibrillation catheter may further include an inflatable and defibrillable balloon provided at the tip of the tubular member, and a supply tube for supplying fluid to the balloon. With this configuration, when the first defibrillation catheter is inserted into a blood vessel and fluid is supplied to the balloon to expand it, the balloon receives a force from the blood flowing through the blood vessel. This allows the first defibrillation catheter to move forward with the flow of blood, simplifying the insertion of the first defibrillation catheter.

In some embodiments, the first defibrillation catheter may further include an insertion tube for inserting a guidewire, the insertion tube being disposed within the tubular member and extending from the base end of the tubular member to the tip of the tubular member. With this configuration, the first defibrillation catheter can be advanced along the guidewire while the guidewire is inserted into the blood vessel. This simplifies the insertion process of the first defibrillation catheter.

In some embodiments, the first defibrillation catheter may further include an insertion tube for inserting a guidewire, the insertion tube being disposed within the tubular member and extending from the outer circumferential surface to the tip of the tubular member. With this configuration, the first defibrillation catheter can be advanced along the guidewire while the guidewire is inserted into the blood vessel. This simplifies the insertion process of the first defibrillation catheter.

In some embodiments, each of the multiple first electrodes may have a curved shape that is convex in a direction intersecting the axial direction. The longer the length of the first electrode in the axial direction, the less flexible and pliable the first defibrillation catheter is, and the more the operability of the first defibrillation catheter is impaired. The smaller the area of contact between the first electrode and the surrounding tissue, the greater the current density when a voltage is applied to the first electrode, and the greater the possibility of damaging the surrounding tissue. In the above configuration, the surface area of the first electrode can be increased without increasing its length in the axial direction. Therefore, the possibility of damaging the surrounding tissue can be reduced without compromising the operability of the first defibrillation catheter.

In some embodiments, the first defibrillation catheter may further have an insulating member that fills a recess defined by the axial end face and outer peripheral surface of one of the first electrodes. When a recess is formed by the axial end face of the first electrode and the outer peripheral surface of the tubular member, when a voltage is applied to the first electrode, the current density increases at the periphery of the end face. In the above configuration, the recess is filled with the insulating member, so that the increase in current density at the periphery of the end face when a voltage is applied to the first electrode can be suppressed. Therefore, the possibility of damaging surrounding tissue can be reduced.

This disclosure makes it possible to improve defibrillation efficiency.

FIG. 1 is a schematic diagram of an intracardiac defibrillation system according to one embodiment. FIG. 2 is a schematic diagram of the defibrillation catheter shown in FIG. FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 4 is an enlarged view of the electrode shown in FIG. FIG. 5 is a flow chart showing a series of steps of a defibrillation method performed by the defibrillator shown in FIG. FIG. 6 is a diagram showing an example of a connection state of the switching circuit in the map mode. FIG. 7 is a diagram showing an example of the connection state of the switching circuit when measuring the resistance value in the intracardiac defibrillation mode. FIG. 8 is a diagram showing another example of the connection state of the switching circuit when measuring the resistance value in the intracardiac defibrillation mode. FIG. 9 is a diagram showing yet another example of the connection state of the switching circuit when measuring the resistance value in the intracardiac defibrillation mode. FIG. 10 is a diagram showing yet another example of the connection state of the switching circuit when measuring the resistance value in the intracardiac defibrillation mode. FIG. 11 is a diagram showing waveforms of voltages applied by the power supply circuit shown in FIG. FIG. 12 is a diagram showing an example of a connection state of the switching circuit when a voltage is applied in the intracardiac defibrillation mode. FIG. 13 is a diagram showing another example of the connection state of the switching circuit when a voltage is applied in the intracardiac defibrillation mode. FIG. 14 is a diagram showing yet another example of the connection state of the switching circuit when a voltage is applied in the intracardiac defibrillation mode. FIG. 15 is a diagram showing yet another example of the connection state of the switching circuit when a voltage is applied in the intracardiac defibrillation mode. FIG. 16 is a schematic diagram of a modified defibrillation catheter. FIG. 17 is a cross-sectional view taken along line XVII-XVII in FIG. FIG. 18 is a schematic diagram of a defibrillation catheter according to another modified example. FIG. 19 is a schematic diagram of a defibrillation catheter according to still another modified example.

Embodiments of the present disclosure will be described in detail below with reference to the drawings. Note that in the description of the drawings, the same elements are given the same reference numerals, and duplicate descriptions will be omitted.

An intracardiac defibrillation system according to one embodiment will be described with reference to Figures 1 to 4. Figure 1 is a schematic diagram of an intracardiac defibrillation system according to one embodiment. Figure 2 is a schematic diagram of a defibrillation catheter shown in Figure 1. Figure 3 is a cross-sectional view taken along line III-III in Figure 2. Figure 4 is an enlarged view of the electrode shown in Figure 2.

The intracardiac defibrillation system 1 shown in FIG. 1 is a system for performing defibrillation. Defibrillation is the process of returning a fibrillating heart to normal. Fibrillation refers to a state in which the cardiac muscle is in spasm. Examples of fibrillation include atrial fibrillation and ventricular fibrillation. The intracardiac defibrillation system 1 performs defibrillation by electrically resetting the area in which the cardiac muscle is in spasm. The intracardiac defibrillation system 1 is used, for example, to treat atrial fibrillation by catheter ablation. The intracardiac defibrillation system 1 includes a defibrillation catheter 2A (first defibrillation catheter), a defibrillation catheter 2B (second defibrillation catheter), a return electrode 3, an electrocardiograph 4, and a defibrillator 10.

Defibrillation catheters 2A and 2B are devices used to perform defibrillation in the cardiac chambers of patient P. As shown in Figures 2 and 3, each of defibrillation catheters 2A and 2B includes a tube 21 (tubular member), an electrode group 22, an electrode group 23, a lead wire group 24, a lead wire group 25, a distal tip 26, a pull wire 27, and a handle 28.

The tube 21 is a long tubular member. The tube 21 is made of, for example, a high-hardness nylon elastomer. An example of a nylon elastomer is PEBAX (registered trademark). The tubes 21 may have different hardnesses in the axial direction of the tube 21. For example, the tube 21 is configured so that the hardness increases stepwise from the tip 21a to the base end 21b of the tube 21. The hardness of the tube 21 (hardness measured with a D-type hardness scale) is, for example, 40 to 75. The outer diameter of the tube 21 is, for example, 1.2 mm to 2.4 mm.

The tube 21 includes a braid 21c. The braid 21c is a member that reinforces the tube 21. The braid 21c is a braided wire made of a metal material. The braid 21c is made of, for example, stainless steel wire. The braid 21c is provided around the entire circumference of the tube 21, from the base end of the tube 21 to just before the electrode group 22. The braid 21c is not provided in the region of the tube 21 where the electrode group 22 is provided.

The electrode group 22 includes a plurality of electrodes 22a. Each electrode 22a is a member for applying defibrillation energy to a desired position in the cardiac cavity. Each electrode 22a is provided on the outer peripheral surface of the tube 21. Specifically, each electrode 22a is provided on the outer peripheral surface of the tube 21 so as to surround the tube 21 around the axis (central axis) of the tube 21. Each electrode 22a has a cylindrical shape with both ends open. As shown in FIG. 4, in this embodiment, each electrode 22a has an olive shape. In other words, each electrode 22a has a curved shape that is convex in a direction intersecting the axial direction of the tube 21. Specifically, each electrode 22a has a streamlined shape in which the outer diameter is largest at the center of the electrode 22a in the axial direction of the tube 21, and the outer diameter gradually decreases from the center toward both ends of the electrode 22a in the axial direction of the tube 21.

Because the outer circumferential surface of the electrode 22a and the outer circumferential surface of the tube 21 are not located on the same plane, a recess 22s is formed between the end face of the electrode 22a and the outer circumferential surface of the tube 21. The defibrillation catheters 2A and 2B further include a glue G (insulating member) that is provided to fill the recess 22s. The glue G smoothly connects the outer circumferential surface of the electrode 22a and the outer circumferential surface of the tube 21 so that no edge is formed between the outer circumferential surface of the electrode 22a and the outer circumferential surface of the tube 21.

If the length of each electrode 22a in the axial direction of the tube 21 is too short, the current density may become excessive when a voltage is applied. If the length of each electrode 22a in the axial direction of the tube 21 is too long, the flexibility and pliability of the portion of the tube 21 where the electrode group 22 is provided may be impaired. From these viewpoints, the length of each electrode 22a in the axial direction of the tube 21 is, for example, 4 mm. From the viewpoint of improving contrast (X-ray opacity) to X-rays, each electrode 22a may be made of a platinum-based alloy such as a platinum-iridium alloy.

The electrodes 22a are arranged in the axial direction of the tube 21. In this embodiment, the electrodes 22a are provided at the tip of the tube 21 and are arranged at equal intervals in the axial direction of the tube 21. The distance between two adjacent electrodes 22a is about 1 to 5 mm. The number of electrodes 22a included in the electrode group 22 may be determined according to the length and arrangement interval of the electrodes 22a in the axial direction of the tube 21, and is, for example, about 6 to 16. In this embodiment, the electrode group 22 includes eight electrodes 22a.

Each electrode 22a is electrically connected to the defibrillation device 10 by a lead wire 24a described below. A voltage of the same polarity is applied to the multiple electrodes 22a (first electrodes) of the electrode group 22 (first electrode group) included in the defibrillation catheter 2A. A voltage of the same polarity is applied to the multiple electrodes 22a (second electrodes) of the electrode group 22 (second electrode group) included in the defibrillation catheter 2B. A voltage of a different polarity from the polarity of the voltage applied to the multiple electrodes 22a included in the defibrillation catheter 2A or a voltage of the same polarity may be applied to the multiple electrodes 22a included in the defibrillation catheter 2B.

When the defibrillation catheters 2A and 2B are used to defibrillate atrial fibrillation, the electrode group 22 of the defibrillation catheters 2A and 2B is placed, for example, in the right atrial lateral wall, the right atrial posterior wall, the right atrial anterior wall, the junction between the superior vena cava and the right atrium, the junction between the inferior vena cava and the right atrium, the left atrial lateral wall, the left atrial posterior wall, the left atrial anterior wall, the junction between the right upper pulmonary vein and the left atrium, the junction between the right lower pulmonary vein and the left atrium, the junction between the left upper pulmonary vein and the left atrium, the junction between the left lower pulmonary vein and the left atrium, the septum between the right atrium and the left atrium, the junction between the atrial septum and the ventricular septum, the esophagus, or the coronary sinus.

The electrode group 23 includes a plurality of electrodes 23a. Each electrode 23a is a member for measuring an intracardiac potential. Each electrode 23a is provided on the outer peripheral surface of the tube 21. Specifically, each electrode 23a is provided on the outer peripheral surface of the tube 21 so as to surround the tube 21 around the axis of the tube 21. Each electrode 23a has a cylindrical shape with both ends open. As shown in FIG. 4, in this embodiment, each electrode 23a has a cylindrical shape with a substantially uniform outer diameter over the entire length of the electrode 23a in the axial direction of the tube 21. The length of each electrode 23a in the axial direction of the tube 21 is, for example, 0.5 mm to 2.0 mm. Each electrode 23a may be made of a platinum-based alloy, such as a platinum-iridium alloy, from the viewpoint of improving contrast to X-rays.

The electrodes 23a are arranged in the axial direction of the tube 21. In this embodiment, the electrodes 23a are provided in the tube 21 at positions spaced from the electrode group 22 toward the base end 21b, and are arranged at equal intervals in the axial direction of the tube 21. The number of electrodes 23a included in the electrode group 23 may be determined according to the length and spacing of the electrodes 23a, and is, for example, about 1 to 8. In this embodiment, the electrode group 23 includes four electrodes 23a. Note that no voltage for defibrillation is applied to the electrodes 23a.

The lead wire group 24 includes a plurality of lead wires 24a. Each lead wire 24a is a member for electrically connecting the electrode 22a to the defibrillator 10. The plurality of lead wires 24a are connected to different electrodes 22a. For example, the number of lead wires 24a included in the lead wire group 24 is the same as the number of electrodes 22a included in the electrode group 22. Each lead wire 24a is inserted into the tube 21, one end of the lead wire 24a is connected to the electrode 22a, and the other end of the lead wire 24a is connected to the connector 28d of the handle 28. Specifically, one end of the lead wire 24a is welded to the inner surface of the electrode 22a, and the lead wire 24a is inserted into the inside of the tube 21 from a through hole provided in the tube wall of the tube 21 and extends to the connector 28d.

Each lead wire 24a is a resin-coated wire that includes a metal conductor and a coating resin that coats the outer surface of the metal conductor. Examples of coating resins include polyimide resin, polyamide resin, and polyamideimide resin. The coating resin has a thickness of, for example, about 10 μm to 50 μm.

The lead wire group 25 includes a plurality of lead wires 25a. Each lead wire 25a is a member for electrically connecting the electrode 23a to the defibrillator 10. The plurality of lead wires 25a are connected to different electrodes 23a. For example, the number of lead wires 25a included in the lead wire group 25 is the same as the number of electrodes 23a included in the electrode group 23. Each lead wire 25a is inserted into the tube 21, one end of the lead wire 25a is connected to the electrode 23a, and the other end of the lead wire 25a is connected to the connector 28d of the handle 28. Specifically, one end of the lead wire 25a is welded to the inner surface of the electrode 23a, and the lead wire 25a is inserted into the inside of the tube 21 from a through hole provided in the tube wall of the tube 21 and extends to the connector 28d.

Each lead wire 25a is a resin-coated wire that includes a metal conductor and a resin coating that coats the outer surface of the metal conductor. Examples of resin coatings include polyimide resin, polyamide resin, and polyamideimide resin. The thickness of the resin coating is, for example, about 10 μm to 50 μm.

The tip tip 26 is a member for sealing the tip 21a of the tube 21. The tip tip 26 is attached to the tip 21a of the tube 21. The tip of the tip tip 26 has a hemispherical shape. The length of the tip tip 26 in the axial direction of the tube 21 is, for example, 0.5 mm to 2.0 mm. In this embodiment, one end of the pull wire 27 is fixed to the tip tip 26 (its inner surface).

The tip tip 26 is made of, for example, a metal material. From the viewpoint of improving contrast with respect to X-rays, the tip tip 26 may be made of platinum, a platinum alloy, tungsten, a tungsten alloy, silver, or a silver alloy. The tip tip 26 may be made of a resin. A resin having a certain degree of flexibility may be used as the resin. Examples of such resins include polyolefins such as polyethylene, polypropylene, ethylene-propylene copolymer, and ethylene-vinyl acetate copolymer, thermoplastic resins such as soft polyvinyl chloride, polyamide, polyamide elastomer, and polyurethane, silicone rubber, and latex rubber.

The pull wire 27 is a member for deflecting the tip of the tube 21. The pull wire 27 is inserted through the tube 21 and is disposed at a position eccentric to the central axis of the tube 21. One end of the pull wire 27 is fixed to the tip tip 26 at a position eccentric to the central axis of the tube 21. One end of the pull wire 27 is fixed to the tip tip 26 by, for example, soldering. One end of the pull wire 27 may be provided with a large diameter portion for preventing it from coming off. With this configuration, the tip tip 26 and one end of the pull wire 27 can be firmly connected, so that the tip tip 26 is prevented from falling off. The other end of the pull wire 27 is connected to the operating lever 28b (operating portion) of the handle 28.

The pull wire 27 is made of, for example, a metal material. Examples of metal materials include stainless steel and nickel-titanium superelastic alloys. The pull wire 27 does not have to be made of a metal material, and may be made of, for example, a high-strength non-conductive wire.

The defibrillation catheters 2A and 2B may include multiple pull wires 27. For example, if two pull wires 27 are arranged symmetrically with respect to the central axis of the tube 21, the tip of the tube 21 can be deflected in two directions.

The handle 28 is used to operate the defibrillation catheters 2A and 2B. The handle 28 is provided at the base end 21b of the tube 21. The handle 28 includes a main body 28a, an operating lever 28b, a strain relief 28c, and a connector 28d.

The main body 28a is the portion that is grasped by the user who operates the defibrillation catheters 2A, 2B. The main body 28a is connected to the base end 21b of the tube 21. The main body 28a is a cylindrical member, and the lead wire 24a, lead wire 25a, and pull wire 27 extending from the tube 21 are inserted inside the main body 28a while being electrically insulated from each other.

The operating lever 28b is a member for moving the pull wire 27 forward and backward in the axial direction of the tube 21. The operating lever 28b may be of a rotating or sliding type. When the user operates the operating lever 28b, the pull wire 27 is pulled, which causes the tip of the tube 21 to deflect. The deflected shape of the tip of the tube 21 is equivalent to that of a typical catheter for electrophysiological testing that is already commercially available.

The strain relief 28c is a member for reinforcing the connection between the tube 21 and the main body 28a. The strain relief 28c is provided to cover the connection around the axis of the tube 21, and has a conical shape that tapers toward the tip 21a of the tube 21.

The connector 28d is a member located at the end of the multiple lead wires 24a and multiple lead wires 25a. Each lead wire 24a and each lead wire 25a is connected to a connector pin of the connector 28d. The connector 28d of the defibrillation catheter 2A is connected to the connector 10a (first connector) of the defibrillation device 10 described below via a cable. The connector 28d of the defibrillation catheter 2B is connected to the connector 10b (second connector) of the defibrillation device 10 described below via a cable.

The counter electrode 3 is a device (electrode) used to perform defibrillation on the body surface of the patient P. The counter electrode 3 is attached to the body surface and applies defibrillation energy from the body surface. The counter electrode 3 is, for example, a conductive counter electrode. In this embodiment, the counter electrode 3 is a plate material having a rectangular shape. The counter electrode 3 is attached to the body surface such that the long side of the counter electrode 3 faces the defibrillation catheters 2A, 2B. The counter electrode 3 may be a circular plate material. A voltage of a polarity different from the polarity of the voltage applied to the multiple electrodes 22a of at least one of the defibrillation catheters 2A, 2B is applied to the counter electrode 3.

The electrocardiograph 4 is a device that measures the intracardiac potential of the patient P. The electrocardiograph 4 measures the potential of the multiple electrodes 23a (third electrodes) of the electrode group 23 (third electrode group) included in the defibrillation catheter 2A and the potential of the multiple electrodes 23a (fourth electrodes) of the electrode group 23 (fourth electrode group) included in the defibrillation catheter 2B. The electrocardiograph 4 may measure the potential of the multiple electrodes 22a of the electrode groups 22 included in the defibrillation catheters 2A and 2B when no voltage is applied to these electrodes 22a. The electrocardiograph 4 outputs the intracardiac potential to the defibrillation device 10.

The defibrillator 10 is a device that supplies defibrillation energy for defibrillation. The defibrillator 10 is sometimes called a console. The defibrillator 10 supplies defibrillation energy between the components by applying voltages of different polarities to one or more members selected from the three components of the electrode group 22 included in the defibrillation catheter 2A, the electrode group 22 included in the defibrillation catheter 2B, and the return electrode plate 3, and to one or more of the remaining components. The defibrillator 10 applies voltages of the same polarity to the multiple electrodes 22a included in the electrode group 22 of the defibrillation catheter 2A, and applies voltages of the same polarity to the multiple electrodes 22a included in the electrode group 22 of the defibrillation catheter 2B.

For example, the defibrillator 10 supplies defibrillation energy between the electrode group 22 of the defibrillation catheter 2A and the electrode group 22 of the defibrillation catheter 2B by applying a voltage of a different polarity to the electrode group 22 of the defibrillation catheter 2B from the polarity of the voltage applied to the electrode group 22 of the defibrillation catheter 2A. The defibrillator 10 supplies defibrillation energy between the electrode group 22 of the defibrillation catheter 2A and the electrode group 22 of the defibrillation catheter 2B by applying a voltage of a different polarity to the electrode group 22 of the defibrillation catheter 2A from the electrode group 22 of the defibrillation catheter 2A to the electrode plate 3. The defibrillator 10 does not apply a voltage to the multiple electrodes 23a included in the electrode group 23.

The defibrillator 10 includes connector 10a, connector 10b, connector 10c (third connector), connector 10d, connector 10e, connector 10f, and connector 10g.

The connector 10a is a connector for connecting the defibrillation catheter 2A. The connector 10a is connected to the connector 28d of the defibrillation catheter 2A by a cable. The connector 10b is a connector for connecting the defibrillation catheter 2B. The connector 10b is connected to the connector 28d of the defibrillation catheter 2B by a cable. The connectors 10a and 10b may be divided into a connector for connecting the electrode group 22 and a connector for connecting the electrode group 23. The connector 10c is a connector for connecting the return electrode plate 3. The connector 10c is connected to the return electrode plate 3 by a cable.

Connectors 10d, 10e, and 10f are connectors for connecting the electrocardiograph 4. The intracardiac potential measured by the defibrillation catheter 2A is output from connector 10d to the electrocardiograph 4. The intracardiac potential measured by the defibrillation catheter 2B is output from connector 10e to the electrocardiograph 4. The intracardiac potential from the electrocardiograph 4 is input to connector 10f and supplied to the calculation processing unit 15.

The connector 10g is a connector for connecting an induction electrode attached to the body surface of the patient P. The body surface electrocardiogram waveform measured by the induction electrode is input to the connector 10g and supplied to the calculation processing unit 15.

The defibrillator 10 includes an operating device 11, a power supply circuit 12, a measuring device 13, a switching circuit 14, and a calculation processing unit 15.

The operation device 11 is a section through which the user operates the defibrillator 10. The operation device 11 includes a display unit 11a and an input unit 11b. The display unit 11a is a section that displays various information. The display unit 11a is, for example, a display such as an LCD (Liquid Crystal Display). The input unit 11b is a section through which the user performs various operations. The input unit 11b is, for example, configured with a physical button switch. Examples of the button switch include a changeover switch for switching the operation mode of the defibrillator 10, a setting switch for setting the defibrillation energy, a charging switch for charging the capacitor included in the power supply circuit 12, and an application switch (discharge switch) for applying the defibrillation energy. The input unit 11b outputs various signals indicating the user's operations to the calculation processing unit 15.

The display unit 11a and the input unit 11b may be integrated into one unit, such as a touch panel. In this case, the input unit 11b may be configured as button icons displayed on the touch panel.

The power supply circuit 12 is a device that supplies a DC voltage. The power supply circuit 12 applies a DC voltage to the electrodes 22a and the counter electrode 3 included in the defibrillation catheters 2A and 2B. The power supply circuit 12 has an output terminal 12a (first terminal) and an output terminal 12b (second terminal). The power supply circuit 12 supplies defibrillation energy by applying a voltage to the electrode 22a or the counter electrode 3 connected to the output terminal 12a and the electrode 22a connected to the output terminal 12b. The target to which the voltage is applied connected to the output terminals 12a and 12b is selectively switched by the switching circuit 14. The power supply circuit 12 has a built-in capacitor. When a user operates a charging switch to output a charging command to the calculation processing unit 15, the calculation processing unit 15 performs a charging process, thereby charging the capacitor of the power supply circuit 12.

The measuring device 13 is a resistance meter that measures the resistance of the path to which the voltage is supplied. The measuring device 13 has measuring terminals 13a and 13b, and measures the resistance between the measuring terminals 13a and 13b. The measurement objects connected to the measuring terminals 13a and 13b are selectively switched by the switching circuit 14. The resistance between the measuring terminals 13a or 13b and the electrode group 22 of the defibrillation catheter 2A, the resistance between the measuring terminals 13a or 13b and the electrode group 22 of the defibrillation catheter 2B, and the resistance between the measuring terminal 13a and the counter electrode plate 3 are negligibly small. Therefore, the measuring device 13 essentially measures the resistance between the electrode connected to the measuring terminal 13a and the electrode connected to the measuring terminal 13b among the multiple electrodes 22a and the counter electrode plate 3 included in the defibrillation catheters 2A and 2B.

The switching circuit 14 is a circuit that switches electrically connected paths. The switching circuit 14 is configured to be able to selectively switch between the member (first member) connected to the output terminal 12a of the power supply circuit 12 and the member (second member) connected to the output terminal 12b of the power supply circuit 12 among the electrode group 22 of the defibrillation catheter 2A, the electrode group 22 of the defibrillation catheter 2B, and the counter electrode plate 3. The switching circuit 14 is configured to be able to selectively switch between the member connected to the measurement terminal 13a of the measuring device 13 and the member connected to the measurement terminal 13b of the measuring device 13 among the electrode group 22 of the defibrillation catheter 2A, the electrode group 22 of the defibrillation catheter 2B, and the counter electrode plate 3. The switching circuit 14 includes switches 41 to 47.

The switches 41 and 42 are circuit elements that selectively switch between the power supply circuit 12 and the measuring device 13. The switch 41 has contacts 41a, 41b, and 41c. The contact 41a is connected to a contact 43b of the switch 43, a contact 44b of the switch 44, and a contact 45b of the switch 45, which will be described later. The contact 41b is connected to the output terminal 12a of the power supply circuit 12. The contact 41c is connected to the measuring terminal 13a of the measuring device 13. The switch 41 selectively switches between a state in which the contacts 41a and 41b are connected and a state in which the contacts 41a and 41c are connected in response to a switching signal from the calculation processing unit 15.

The switch 42 has contacts 42a, 42b, and 42c. The contact 42a is connected to the contact 43c of the switch 43 and the contact 44c of the switch 44. The contact 42b is connected to the output terminal 12b of the power supply circuit 12. The contact 42c is connected to the measurement terminal 13b of the measuring device 13. The switch 42 selectively switches between a state in which the contacts 42a and 42b are connected and a state in which the contacts 42a and 42c are connected in response to a switching signal from the calculation processing unit 15.

Switch 41 and switch 42 work together to perform switching operations. When contacts 41a and 41b are connected in switch 41, contacts 42a and 42b are connected in switch 42. When contacts 41a and 41c are connected in switch 41, contacts 42a and 42c are connected in switch 42.

The switch 43 is a circuit element that selectively switches the connection destination of the electrode group 22 of the defibrillation catheter 2A. The switch 43 has contacts 43a, 43b, 43c, and 43d. The contact 43a is connected to the connector 10a. Specifically, the contact 43a is connected to the electrode group 22 of the defibrillation catheter 2A via the connector 10a. The contact 43b is connected to the contact 41a. The contact 43c is connected to the contact 42a. The contact 43d is connected to the connector 10d. The switch 43 selectively switches between a state in which the contacts 43a and 43b are connected, a state in which the contacts 43a and 43c are connected, and a state in which the contacts 43a and 43d are connected in response to a switching signal from the calculation processing unit 15.

The switch 44 is a circuit element that selectively switches the connection destination of the electrode group 22 of the defibrillation catheter 2B. The switch 44 has contacts 44a, 44b, 44c, and 44d. The contact 44a is connected to the connector 10b. Specifically, the contact 44a is connected to the electrode group 22 of the defibrillation catheter 2B via the connector 10b. The contact 44b is connected to the contact 41a. The contact 44c is connected to the contact 42a. The contact 44d is connected to the connector 10e. The switch 44 selectively switches between a state in which the contacts 44a and 44b are connected, a state in which the contacts 44a and 44c are connected, and a state in which the contacts 44a and 44d are connected in response to a switching signal from the calculation processing unit 15.

The switch 45 is a circuit element that switches the connection state of the return electrode plate 3. The switch 45 has a contact 45a and a contact 45b. The contact 45a is connected to the connector 10c. Specifically, the contact 45a is connected to the return electrode plate 3 via the connector 10c. The contact 45b is connected to the contact 41a. In response to a switching signal from the calculation processing unit 15, the switch 45 selectively switches between a conductive state (on state) in which the contacts 45a and 45b are connected, and a disconnected state (off state) in which the contacts 45a and 45b are disconnected.

The switch 46 is a circuit element that selectively switches the connection destination of the electrode group 23 of the defibrillation catheter 2A. The switch 46 has contacts 46a, 46b, and 46c. The contact 46a is connected to the connector 10a. Specifically, the contact 46a is connected to the electrode group 23 of the defibrillation catheter 2A via the connector 10a. The contact 46b is connected to the connector 10d. The contact 46c is connected to the arithmetic processing unit 15. In response to a switching signal from the arithmetic processing unit 15, the switch 46 selectively switches between a state in which the contacts 46a and 46b are connected and a state in which the contacts 46a and 46c are connected.

The switch 47 is a circuit element that selectively switches the connection destination of the electrode group 23 of the defibrillation catheter 2B. The switch 47 has contacts 47a, 47b, and 47c. The contact 47a is connected to the connector 10b. Specifically, the contact 47a is connected to the electrode group 23 of the defibrillation catheter 2B via the connector 10b. The contact 47b is connected to the connector 10e. The contact 47c is connected to the arithmetic processing unit 15. The switch 47 selectively switches between a state in which the contacts 47a and 47b are connected and a state in which the contacts 47a and 47c are connected in response to a switching signal from the arithmetic processing unit 15.

The arithmetic processing unit 15 is a controller that controls the defibrillator 10. The arithmetic processing unit 15 controls, for example, the operation device 11, the power supply circuit 12, the measuring device 13, and the switching circuit 14. The arithmetic processing unit 15 performs various controls based on various signals output from the input unit 11b. When a user operates the charge switch to output a charge command from the input unit 11b to the arithmetic processing unit 15, the arithmetic processing unit 15 controls the power supply circuit 12 so that the defibrillation energy (voltage) set by the setting switch is charged to the capacitor of the power supply circuit 12.

When a user operates the discharge switch to output a discharge command from the input unit 11b to the arithmetic processing unit 15, the arithmetic processing unit 15 controls the power supply circuit 12 to release the defibrillation energy (voltage) charged in the capacitor of the power supply circuit 12. In this embodiment, when the resistance value measured by the measuring device 13 is within an appropriate range, the arithmetic processing unit 15 applies a voltage to the power supply circuit 12 in synchronization with the peak of the R wave.

When the user operates the selector switch to select an operating mode, the calculation processing unit 15 operates the defibrillator 10 in the selected operating mode. The operating modes include a map mode (electric potential measurement mode) and an intracardiac defibrillation mode. When the defibrillator 10 is started up, the operating mode of the defibrillator 10 is initially set to the map mode.

Next, the defibrillation method performed by the defibrillator 10 will be described with reference to Figs. 5 to 15. Fig. 5 is a flow chart showing a series of processes of the defibrillation method performed by the defibrillator shown in Fig. 1. Fig. 6 is a diagram showing an example of the connection state of the switching circuit in the map mode. Figs. 7 to 10 are diagrams showing an example of the connection state of the switching circuit when measuring resistance values in the intracardiac defibrillation mode. Fig. 11 is a diagram showing the waveform of the voltage applied by the power supply circuit shown in Fig. 1. Figs. 12 to 15 are diagrams showing an example of the connection state of the switching circuit when applying voltage in the intracardiac defibrillation mode. Note that, for convenience of explanation, in Figs. 6 to 10 and Figs. 12 to 15, the connectors are omitted, and the path to which the electrode group 22 is connected and the path to which the electrode group 23 is connected are shown separately.

When defibrillation treatment is performed, first, defibrillation catheters 2A and 2B are inserted into the cardiac cavity of patient P, and the electrode group 22 of each defibrillation catheter is placed at the desired position. The return electrode 3 is attached to the desired position on the body surface of patient P. Then, the power of the defibrillator 10 is turned on, and the defibrillator 10 is started up. The defibrillation catheter 2A is connected to the connector 10a of the defibrillator 10, the defibrillation catheter 2B is connected to the connector 10b of the defibrillator 10, and the return electrode 3 is connected to the connector 10c of the defibrillator 10. When the defibrillator 10 is started up, it operates in map mode.

6, when the defibrillator 10 operates in the map mode, the contacts 43a and 43d of the switch 43 are connected, the contacts 44a and 44d of the switch 44 are connected, the contacts 46a and 46b of the switch 46 are connected, and the contacts 47a and 47b of the switch 47 are connected. This connects the electrode group 22 and the electrode group 23 of the defibrillation catheter 2A and the electrode group 22 and the electrode group 23 of the defibrillation catheter 2B to the electrocardiograph 4. The switch 45 may be set to either a conductive state or a cut-off state. The switch 41 is set to a state in which the contact 41a is not connected to any contact. Similarly, the switch 42 is set to a state in which the contact 42a is not connected to any contact.

With this configuration, the intracardiac potential measured by the electrode group 22 and electrode group 23 of the defibrillation catheter 2A and the electrode group 22 and electrode group 23 of the defibrillation catheter 2B is output to the electrocardiograph 4. The intracardiac potential is then output from the electrocardiograph 4 to the defibrillator 10, and the arithmetic processing unit 15 receives the intracardiac potential. The arithmetic processing unit 15 then outputs the intracardiac potential to the display unit 11a, causing it to be displayed on the display unit 11a. In this state, when the user operates the selector switch to select intracardiac defibrillation mode, the series of processes shown in FIG. 5 is started.

As shown in FIG. 5, first, the calculation processing unit 15 determines whether a combination to be used in the intracardiac defibrillation mode has been selected from the defibrillation catheters 2A and 2B and the return electrode plate 3 (step S1). When the intracardiac defibrillation mode is selected, for example, selectable combination candidates are displayed on the display unit 11a. The selectable combination candidates are combinations of members to which voltages of different polarities are applied, and include a combination of the defibrillation catheter 2A and the defibrillation catheter 2B, a combination of the defibrillation catheter 2A and the return electrode plate 3 and the defibrillation catheter 2B, a combination of the defibrillation catheter 2B and the return electrode plate 3 and the defibrillation catheter 2A, and a combination of the return electrode plate 3 and the defibrillation catheters 2A and 2B.

When the calculation processing unit 15 determines that a combination has not been selected (step S1: NO), it repeats step S1 until a combination is selected. On the other hand, when the user selects a desired combination to be used for defibrillation from among the candidate combinations, the calculation processing unit 15 determines that the combination has been selected (step S1: YES) and performs a resistance value measurement process (step S2).

In step S2, first, the calculation processing unit 15 sets the connection state of the switching circuit 14 to a connection state corresponding to the selected combination in order to measure the resistance value between two electrodes (components) to which voltages of different polarities included in the selected combination are supplied. At this time, the intracardiac potential (intracardiac electrocardiogram) due to the electrode group 22 is no longer displayed on the display unit 11a, but the intracardiac potential (intracardiac electrocardiogram) due to the electrode group 23 is displayed. Then, the calculation processing unit 15 causes the measuring device 13 to measure the resistance value between the measurement terminals 13a and 13b.

Now, with reference to Figures 7 to 10, we will explain some examples of the connection state of the switching circuit 14 when measuring resistance values in the intracardiac defibrillation mode.

For example, when the combination of defibrillation catheter 2A and defibrillation catheter 2B is selected, the connection state of the switching circuit 14 is set to the connection state shown in FIG. 7. Specifically, the contact 41a and the contact 41c of the switch 41 are connected, the contact 42a and the contact 42c of the switch 42 are connected, the contact 43a and the contact 43b of the switch 43 are connected, and the contact 44a and the contact 44c of the switch 44 are connected. At this time, the switch 45 is set to the cut-off state, the contact 46a and the contact 46b of the switch 46 are connected, and the contact 47a and the contact 47b of the switch 47 are connected. According to this configuration, the electrode group 22 of the defibrillation catheter 2A is connected to the measurement terminal 13a, and the electrode group 22 of the defibrillation catheter 2B is connected to the measurement terminal 13b, so that the resistance value between the electrode group 22 of the defibrillation catheter 2A and the electrode group 22 of the defibrillation catheter 2B is measured.

When the combination of the defibrillation catheter 2A and the counter electrode plate 3 with the defibrillation catheter 2B is selected, the connection state of the switching circuit 14 is set to the connection state shown in FIG. 8. The connection state shown in FIG. 8 differs from the connection state shown in FIG. 7 in that the switch 45 is set to the conductive state. With this configuration, the electrode group 22 and the counter electrode plate 3 of the defibrillation catheter 2A are connected to the measurement terminal 13a, and the electrode group 22 of the defibrillation catheter 2B is connected to the measurement terminal 13b, so that the resistance value between the electrode group 22 and the counter electrode plate 3 of the defibrillation catheter 2A and the electrode group 22 of the defibrillation catheter 2B is measured. In other words, the combined resistance value of the circuit in which the resistance component between the electrode group 22 of the defibrillation catheter 2A and the electrode group 22 of the defibrillation catheter 2B and the resistance component between the counter electrode plate 3 and the electrode group 22 of the defibrillation catheter 2B are connected in parallel is measured.

When the combination of the defibrillation catheter 2B and the counter electrode plate 3 with the defibrillation catheter 2A is selected, the connection state of the switching circuit 14 is set to the connection state shown in FIG. 9. The connection state shown in FIG. 9 differs from the connection state of FIG. 8 in the connection state of the switches 43 and 44. Specifically, the contact 43a and the contact 43c of the switch 43 are connected, and the contact 44a and the contact 44b of the switch 44 are connected. With this configuration, the electrode group 22 and the counter electrode plate 3 of the defibrillation catheter 2B are connected to the measurement terminal 13a, and the electrode group 22 of the defibrillation catheter 2A are connected to the measurement terminal 13b, so that the resistance value between the electrode group 22 and the counter electrode plate 3 of the defibrillation catheter 2B and the electrode group 22 of the defibrillation catheter 2A is measured. In other words, the combined resistance of the circuit in which the resistance component between the electrode group 22 of the defibrillation catheter 2B and the electrode group 22 of the defibrillation catheter 2A and the resistance component between the return electrode plate 3 and the electrode group 22 of the defibrillation catheter 2A are connected in parallel is measured.

When the combination of the counter electrode 3 and the defibrillation catheters 2A and 2B is selected, the connection state of the switching circuit 14 is set to the connection state shown in FIG. 10. The connection state shown in FIG. 10 differs from the connection state shown in FIG. 9 in the connection state of the switch 44. Specifically, the contact 44a and the contact 44c of the switch 44 are connected. With this configuration, the counter electrode 3 is connected to the measurement terminal 13a, and the electrode group 22 of the defibrillation catheters 2A and 2B is connected to the measurement terminal 13b, so that the resistance value between the counter electrode 3 and the electrode group 22 of the defibrillation catheters 2A and 2B is measured. In other words, the combined resistance value of the circuit in which the resistance component between the counter electrode 3 and the electrode group 22 of the defibrillation catheter 2A and the resistance component between the counter electrode 3 and the electrode group 22 of the defibrillation catheter 2B are connected in parallel is measured.

The measuring device 13 then outputs the measured resistance value to the calculation processing unit 15.

Next, when the calculation processing unit 15 receives the resistance value from the measuring device 13, it judges whether the resistance value is within an appropriate range (step S3). The appropriate range is preset for each combination. The appropriate range is the range of resistance values that can be measured when the members included in the combination are properly placed. If it is judged that the resistance value is within the appropriate range (step S3: YES), the calculation processing unit 15 sets the charging switch to be operable and judges whether a charging command has been received (step S4). If the calculation processing unit 15 judges that a charging command has not been received (step S4: NO), it repeats step S4 until a charging command is received. Note that the charging switch is set to be inoperable until it is judged in step S3 that the resistance value is within the appropriate range.

On the other hand, when a charging command is output from the input unit 11b to the arithmetic processing unit 15 by the user operating the charging switch, the arithmetic processing unit 15 receives the charging command (step S4: YES) and performs charging processing (step S5). In step S5, the arithmetic processing unit 15 controls the power supply circuit 12 so that the defibrillation energy (voltage) set by the setting switch is charged to the capacitor of the power supply circuit 12. The defibrillation energy is set to, for example, 10 J. The time required to charge the capacitor is, for example, about 5 seconds.

Then, the arithmetic processing unit 15 determines whether or not a discharge command has been received within a predetermined time from the completion of charging (step S6). The predetermined time is set to, for example, about 10 seconds. When a discharge command is output from the input unit 11b to the arithmetic processing unit 15 by the user operating the discharge switch, the arithmetic processing unit 15 receives the discharge command (step S6: YES) and performs a discharge process (step S7). In step S7, first, the arithmetic processing unit 15 sets the connection state of the switching circuit 14 to a connection state corresponding to the selected combination in order to apply voltages of different polarities to the two members (electrodes) included in the selected combination.

The arithmetic processing unit 15 then measures the peak of the R-wave by arithmetically processing the body surface signal input from the induction electrode via the connector 10g. The arithmetic processing unit 15 then outputs a trigger signal to the power supply circuit 12 in synchronization with the peak of the R-wave. Here, the method of calculating the peak of the R-wave will be described in detail. For example, the arithmetic processing unit 15 samples the body surface electrocardiogram at a predetermined period, detects the peak of the R-wave, and measures the rise time and fall time of the R-wave. The sampling period is set to, for example, 1 millisecond. As the R-wave begins to fall once it reaches its peak, the arithmetic processing unit 15 detects the peak by monitoring the rise and fall of the R-wave.

Then, the arithmetic processing unit 15 judges whether the R wave is a normal waveform (narrow) or an abnormal waveform (wide). For example, if the time from when the R wave starts to rise to its peak (rise time) is within 45 milliseconds, the arithmetic processing unit 15 judges that the R wave is a normal waveform. If the time from when the R wave starts to rise to its peak (rise time) is greater than 45 milliseconds, the arithmetic processing unit 15 judges that the R wave is an abnormal waveform.

Then, when the R-wave is determined to be a normal waveform, the calculation processing unit 15 outputs a trigger signal in response to the passage of time t0 (see FIG. 11) from the peak of the R-wave. If voltage is not applied within 60 milliseconds from the peak of the R-wave, there is a risk of inducing ventricular fibrillation. For this reason, time t0 is, for example, 10 milliseconds to 50 milliseconds. In this embodiment, time t0 is set to 10 milliseconds. Note that the conditions for determining a normal waveform, the conditions for determining an abnormal waveform, time t0, etc. are configured to be user-configurable.

Of the intracardiac potentials input to the electrocardiograph 4 via connectors 10d and 10e, one selected by the user using the operation device 11 is input to the arithmetic processing unit 15 via connector 10f. The arithmetic processing unit 15 may output a trigger signal to the power supply circuit 12 in synchronization with the peak of the intracardiac potential input from the electrocardiograph 4 via connector 10f. The method of outputting the trigger signal is the same as when a body surface electrocardiogram measured by an induction electrode is used.

The arithmetic processing unit 15 may directly use the intracardiac potential measured by the electrode group 23 of the defibrillation catheter 2A and the intracardiac potential measured by the electrode group 23 of the defibrillation catheter 2B. In this case, the arithmetic processing unit 15 controls the switching circuit 14 so that the contacts 46a and 46c of the switch 46 are connected, and the contacts 47a and 47c of the switch 47 are connected.

When both the intracardiac potential and the body surface signal are input to the calculation processing unit 15, the calculation processing unit 15 may prioritize the body surface signal and perform calculation processing to detect the peak of the R wave.

Then, when the power supply circuit 12 receives the trigger signal, it releases the defibrillation energy (voltage) that has been charged in the capacitor of the power supply circuit 12. As shown in FIG. 11, in this embodiment, the power supply circuit 12 applies a biphasic voltage between the output terminals 12a and 12b. The horizontal axis of the graph in FIG. 11 represents time, and the vertical axis represents potential.

First, the power supply circuit 12 applies a voltage between the output terminals 12a and 12b so that the output terminal 12a is positive and the output terminal 12b is negative. The voltage applied between the output terminals 12a and 12b is discharged from the capacitor, and therefore decays over time. When time t1 has elapsed since the start of the voltage application, the power supply circuit 12 stops applying the voltage and applies a voltage with the positive and negative reversed between the output terminals 12a and 12b so that the output terminal 12a is negative and the output terminal 12b is positive. Then, when time t2 has elapsed since the start of the application of the reversed voltage, the calculation processing unit 15 outputs a stop signal to the power supply circuit 12, and the power supply circuit 12 stops applying the voltage upon receiving the stop signal.

Time t1 and time t2 are, for example, 1.5 milliseconds to 10.0 milliseconds. The magnitude (absolute value) of peak voltage V1 is, for example, 300 V to 500 V. The power supply circuit 12 may apply a single-phase voltage between output terminal 12a and output terminal 12b. Time t is, for example, 1.0 milliseconds to 30.0 milliseconds. In this embodiment, time t is 20.0 milliseconds. Note that although there is a time required to switch the polarity of the voltage, this time is extremely short. Therefore, time t is slightly greater than the sum of time t1 and time t2, but is substantially equal to them.

Now, with reference to Figures 12 to 15, we will explain some examples of the connection state of the switching circuit 14 when voltage is applied in the intracardiac defibrillation mode.

For example, when a combination of defibrillation catheter 2A and defibrillation catheter 2B is selected, the connection state of the switching circuit 14 is set to the connection state shown in FIG. 12. The connection state shown in FIG. 12 differs from the connection state shown in FIG. 7 in the connection state of switches 41 and 42. Specifically, the contacts 41a and 41b of switch 41 are connected, and the contacts 42a and 42b of switch 42 are connected. With this configuration, the electrode group 22 of defibrillation catheter 2A is connected to output terminal 12a, and the electrode group 22 of defibrillation catheter 2B is connected to output terminal 12b, so that a voltage is applied from output terminal 12a to the electrode group 22 of defibrillation catheter 2A, and a voltage is applied from output terminal 12b to the electrode group 22 of defibrillation catheter 2B. Therefore, defibrillation energy is applied between the electrode group 22 of defibrillation catheter 2A and the electrode group 22 of defibrillation catheter 2B.

When the combination of the defibrillation catheter 2A and the counter electrode plate 3 with the defibrillation catheter 2B is selected, the connection state of the switching circuit 14 is set to the connection state shown in FIG. 13. The connection state shown in FIG. 13 differs from the connection state of FIG. 8 in the connection state of the switches 41 and 42. Specifically, the contacts 41a and 41b of the switch 41 are connected, and the contacts 42a and 42b of the switch 42 are connected. With this configuration, the electrode group 22 and the counter electrode plate 3 of the defibrillation catheter 2A are connected to the output terminal 12a, and the electrode group 22 of the defibrillation catheter 2B is connected to the output terminal 12b, so that a voltage is applied from the output terminal 12a to the electrode group 22 and the counter electrode plate 3 of the defibrillation catheter 2A, and a voltage is applied from the output terminal 12b to the electrode group 22 of the defibrillation catheter 2B. Therefore, defibrillation energy is applied between the electrode group 22 of the defibrillation catheter 2A and the electrode group 22 of the defibrillation catheter 2B, and between the return electrode plate 3 and the electrode group 22 of the defibrillation catheter 2B.

When the combination of the defibrillation catheter 2B and the counter electrode plate 3 with the defibrillation catheter 2A is selected, the connection state of the switching circuit 14 is set to the connection state shown in FIG. 14. The connection state shown in FIG. 14 differs from the connection state of FIG. 9 in the connection state of the switches 41 and 42. Specifically, the contacts 41a and 41b of the switch 41 are connected, and the contacts 42a and 42b of the switch 42 are connected. With this configuration, the electrode group 22 and the counter electrode plate 3 of the defibrillation catheter 2B are connected to the output terminal 12a, and the electrode group 22 of the defibrillation catheter 2A is connected to the output terminal 12b, so that a voltage is applied from the output terminal 12a to the electrode group 22 and the counter electrode plate 3 of the defibrillation catheter 2B, and a voltage is applied from the output terminal 12b to the electrode group 22 of the defibrillation catheter 2A. Therefore, defibrillation energy is applied between the electrode group 22 of the defibrillation catheter 2B and the electrode group 22 of the defibrillation catheter 2A, and between the return electrode plate 3 and the electrode group 22 of the defibrillation catheter 2A.

When the combination of the counter electrode plate 3 and the defibrillation catheters 2A and 2B is selected, the connection state of the switching circuit 14 is set to the connection state shown in FIG. 15. The connection state shown in FIG. 15 differs from the connection state shown in FIG. 10 in the connection state of the switches 41 and 42. Specifically, the contacts 41a and 41b of the switch 41 are connected, and the contacts 42a and 42b of the switch 42 are connected. With this configuration, the counter electrode plate 3 is connected to the output terminal 12a, and the electrode groups 22 of the defibrillation catheters 2A and 2B are connected to the output terminal 12b, so that a voltage is applied to the counter electrode plate 3 from the output terminal 12a, and a voltage is applied to the electrode groups 22 of the defibrillation catheter 2A and the electrode groups 22 of the defibrillation catheter 2B from the output terminal 12b. Therefore, defibrillation energy is applied between the counter electrode plate 3 and the electrode group 22 of the defibrillation catheter 2A, and between the counter electrode plate 3 and the electrode group 22 of the defibrillation catheter 2B.

When the discharge process in step S7 is completed, the calculation processing unit 15 switches the operation mode of the defibrillator 10 to the map mode (step S9). In step S9, the calculation processing unit 15 sets the connection state of the switching circuit 14 to the connection state shown in FIG. 6. This completes the series of processes shown in FIG. 5.

On the other hand, in step S6, if the calculation processing unit 15 does not receive a discharge command until a predetermined time has elapsed since the completion of charging (step S6: NO), the calculation processing unit 15 causes the capacitor of the power supply circuit 12 to internally discharge (step S8). Then, the calculation processing unit 15 switches the operation mode of the defibrillator 10 to the map mode (step S9). With this, the series of processes shown in FIG. 5 is completed.

If it is determined in step S3 that the resistance value is outside the appropriate range (step S3: NO), the calculation processing unit 15 switches the operation mode of the defibrillator 10 to the map mode (step S9). This ends the series of processes shown in FIG. 5. If the resistance value is outside the appropriate range, it is considered that the electrode group 22 or the return electrode 3 is not properly placed. Therefore, while checking the intracardiac potential, the user repositions the defibrillation catheters 2A, 2B and the return electrode 3, which are used for defibrillation, in appropriate positions. After that, the user operates the changeover switch to select the intracardiac defibrillation mode, and the series of processes shown in FIG. 5 is started again.

In the intracardiac defibrillation system 1 described above, the defibrillation catheter 2A has an electrode group 22, and the defibrillation catheter 2B has an electrode group 22. In this way, the two electrode groups 22 are included in different defibrillation catheters, which improves the degree of freedom in placement of the two electrode groups 22. Therefore, the electrode groups 22 of the defibrillation catheter 2A and the electrode groups 22 of the defibrillation catheter 2B can be placed in positions close to the area where the myocardium is spasming. This allows defibrillation energy to be applied efficiently to the area where the myocardium is spasming. As a result, there is no need to set the defibrillation energy higher than necessary, which makes it possible to improve defibrillation efficiency.

The defibrillation device 10 may apply a voltage of a different polarity to the electrode group 22 of the defibrillation catheter 2B from the polarity of the voltage applied to the electrode group 22 of the defibrillation catheter 2A. With this configuration, defibrillation energy can be applied between the electrode group 22 of the defibrillation catheter 2A and the electrode group 22 of the defibrillation catheter 2B.

The defibrillator 10 may apply a voltage of a different polarity to the counter electrode plate 3 than the polarity of the voltage applied to the electrode group 22 of the defibrillator catheter 2A. With this configuration, defibrillation energy can be applied between the electrode group 22 of the defibrillator catheter 2A and the counter electrode plate 3. Similarly, the defibrillator 10 may apply a voltage of a different polarity to the counter electrode plate 3 than the polarity of the voltage applied to the electrode group 22 of the defibrillator catheter 2B. With this configuration, defibrillation energy can be applied between the electrode group 22 of the defibrillator catheter 2B and the counter electrode plate 3.

The switching circuit 14 is configured to selectively switch between the members connected to the output terminal 12a of the power supply circuit 12 and the members connected to the output terminal 12b of the power supply circuit 12 among the electrode group 22 of the defibrillation catheter 2A, the electrode group 22 of the defibrillation catheter 2B, and the counter electrode plate 3. Specifically, a combination of members connected to the output terminal 12a and members connected to the output terminal 12b is selected according to the connection state of the switches 41 to 45. With this configuration, defibrillation can be performed using a combination selected from the electrode group 22 of the defibrillation catheter 2A, the electrode group 22 of the defibrillation catheter 2B, and the counter electrode plate 3. Therefore, an appropriate combination can be selected according to the location where fibrillation has occurred, making it possible to improve defibrillation efficiency.

The switching circuit 14 selectively connects a combination selected from the electrode group 22 of the defibrillation catheter 2A, the electrode group 22 of the defibrillation catheter 2B, and the return electrode plate to either the power supply circuit 12 or the measuring device 13. This configuration allows the defibrillation device 10 to be made smaller than a configuration in which a path for supplying voltage and a path for measuring resistance values are provided separately.

The defibrillation catheters 2A and 2B have an electrode group 23 including a plurality of electrodes 23a. The electrocardiograph 4 measures the potential of the electrode group 23 of the defibrillation catheter 2A and the potential of the electrode group 23 of the defibrillation catheter 2B. Therefore, it is possible to measure intracardiac potentials without using an electrophysiological test catheter.

If the resistance value of the path through which the voltage is supplied is outside the appropriate range, it is believed that the electrode to which the voltage is applied (electrode group 22 or return electrode plate 3) is not properly placed. To perform defibrillation in this state, it is necessary to increase the defibrillation energy. In the intracardiac defibrillation system 1, voltage is applied when the resistance value of the path through which the voltage is supplied is within the appropriate range, so there is no need to increase the defibrillation energy excessively. As a result, defibrillation efficiency can be improved.

As described above, if voltage is not applied within 60 milliseconds of the peak of the R wave or intracardiac potential, there is a risk of inducing ventricular fibrillation. The calculation processing unit 15 applies voltage to the power supply circuit 12 in synchronization with the peak of the R wave or intracardiac potential. Therefore, by applying voltage before 60 milliseconds have elapsed since the peak of the R wave or intracardiac potential, it is possible to prevent the induction of ventricular fibrillation.

In a configuration in which a long electrode in which multiple electrodes 22a are integrated is used, the electrodes extend in the axial direction of the tube 21, reducing the flexibility and softness of the defibrillation catheter. On the other hand, in the defibrillation catheters 2A and 2B, the multiple electrodes 22a are provided on the outer circumferential surface of the tube 21 and arranged in the axial direction of the tube 21. Therefore, compared to a configuration in which a long electrode is used, the flexibility and softness of the defibrillation catheters 2A and 2B can be increased. This makes it possible to improve the operability of the defibrillation catheters 2A and 2B.

In the defibrillation catheters 2A and 2B, the distal tip 26 is provided at the distal end 21a of the tube 21, and one end of the pull wire 27 is fixed to the distal tip 26 at a position eccentric to the central axis of the tube 21. Therefore, by moving the pull wire 27 back and forth with the operating lever 28b, a force is applied to the distal tip 26 at a position eccentric to the central axis. This allows the distal end of the tube 21 (defibrillation catheters 2A and 2B) to be deflected. As a result, the operability of the defibrillation catheters 2A and 2B can be improved.

The longer the length of the electrode 22a in the axial direction of the tube 21, the less flexible and pliable the defibrillation catheters 2A, 2B are, and the more the operability of the defibrillation catheters 2A, 2B is impaired. The smaller the surface area of the electrode 22a, the greater the current density when voltage is applied, and the greater the possibility of damaging the surrounding tissue. Each electrode 22a has a convex curved shape in a direction intersecting the axial direction of the tube 21. With this configuration, the surface area of the electrode 22a can be increased without increasing the length of the electrode 22a in the axial direction of the tube 21. Therefore, the possibility of damaging the surrounding tissue can be reduced without impairing the operability of the defibrillation catheters 2A, 2B.

When a recess 22s is formed by the end face of the electrode 22a in the axial direction of the tube 21 and the outer peripheral surface of the tube 21, when a voltage is applied to the electrode 22a, the current density increases around the edge of the end face of the electrode 22a. In this case, there is a possibility that the surrounding tissue may be damaged or that insulation breakdown may occur. In contrast, in the defibrillation catheters 2A and 2B, the recess 22s is filled with glue G, so that it is possible to prevent an increase in current density around the edge of the end face when a voltage is applied to the electrode 22a. Therefore, it is possible to reduce the possibility of damaging the surrounding tissue.

The power supply circuit 12 and the measuring device 13 are selectively connected to the selected combination depending on the connection state of the switches 41 and 42. Therefore, when a voltage is applied, the measuring device 13 is electrically disconnected from the path to which the voltage is applied. On the other hand, when the resistance value of the path to which the voltage is applied is measured, the power supply circuit 12 is electrically disconnected from the path. Therefore, the defibrillator 10 can be made smaller and the power supply circuit 12 and the measuring device 13 can be prevented from interfering with each other.

Note that the intracardiac defibrillation system disclosed herein is not limited to the above embodiment.

The intracardiac defibrillation system 1 may further include one or more defibrillation catheters having a configuration similar to that of the defibrillation catheters 2A and 2B. The defibrillation device 10 may include connectors for connecting the same number of defibrillation catheters as the number of defibrillation catheters.

The intracardiac defibrillation system 1 may not include a return electrode plate 3. In this case, the defibrillator 10 may not include the connector 10c. The intracardiac defibrillation system 1 may include two or more return electrode plates 3. The defibrillator 10 may include connectors for connecting return electrodes in the same number as the number of return electrode plates 3.

When the intracardiac defibrillation system 1 includes a return electrode 3, it is not necessary to include one of the defibrillation catheters 2A, 2B.

Each electrode 22a, like electrode 23a, may have a cylindrical shape with a substantially uniform outer diameter over the entire length of electrode 22a in the axial direction of tube 21.

Each electrode 22a may be attached to the outer circumferential surface of the tube 21 such that no recess 22s is formed between the outer circumferential surface of the tube 21 and the outer circumferential surface of the electrode 22a. In this case, the defibrillation catheters 2A and 2B may not include the glue G.

Although the defibrillation catheters 2A and 2B are configured so that the tip of the tube 21 can be deflected by the pull wire 27, the mechanism for deflecting the tip of the tube 21 is not limited to this. For example, the defibrillation catheters 2A and 2B may include a leaf spring to deflect the tip of the tube 21 in a planar manner.

The defibrillation catheters 2A and 2B may not include the pull wire 27. In this case, the handle 28 may not include the operating lever 28b.

As shown in Figs. 16 and 17, the defibrillation catheters 2A and 2B may further include a lumen tube 29. Fig. 16 is a schematic diagram of a modified defibrillation catheter. Fig. 17 is a cross-sectional view taken along line XVII-XVII in Fig. 16. The defibrillation catheters 2A and 2B shown in Figs. 16 and 17 differ from the defibrillation catheters 2A and 2B shown in Fig. 2 mainly in that they further include a lumen tube 29 and in the configuration of the handle 28.

In this modified example, the lumen tube 29 is used as an insertion tube for inserting the guide wire 31. The lumen tube 29 is disposed within the tube 21 and extends from the base end 21b to the tip 21a. Specifically, the lumen tube 29 extends linearly in the axial direction of the tube 21. The tip of the lumen tube 29 penetrates the tip tip 26 and extends to the tip of the tip tip 26. The base end of the lumen tube 29 penetrates the handle 28. The lumen tube 29 is disposed, for example, coaxially with the tube 21.

The lumen tube 29 is made of a highly insulating material such as perfluoroalkyl vinyl ether copolymer (PFA) and polytetrafluoroethylene (PTFE). The lumen tube 29 may be made of an antithrombotic material produced by mixing these materials with antithrombotic substances such as heparin, prostaglandin, urokinase, and arginine derivatives.

The handle 28 differs from the handle 28 of the defibrillation catheters 2A and 2B shown in FIG. 2 mainly in that it does not include an operating lever 28b and in the arrangement of the connector 28d. The main body 28a also functions as a hub located at the end of the lumen tube 29. Examples of materials that can be used to make the hub include thermoplastic resins such as polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-styrene copolymer. The connector 28d is arranged in parallel with the main body 28a. In other words, the connector 28d is located off the central axis of the tube 21.

In these defibrillation catheters 2A and 2B, a guide wire is inserted into the lumen tube 29 from the base end of the lumen tube 29 and passes through the defibrillation catheters 2A and 2B. The defibrillation catheters 2A and 2B are then moved along the guide wire to the affected area. These defibrillation catheters 2A and 2B are also called over-the-wire type.

With this configuration, the defibrillation catheters 2A and 2B can be moved along the guide wire 31 while the guide wire 31 is inserted into the blood vessel to reach the affected area. This simplifies the insertion of the defibrillation catheters 2A and 2B.

As shown in FIG. 18, the lumen tube 29 does not have to extend linearly inside the tube 21. FIG. 18 is a schematic diagram of another modified defibrillation catheter. The defibrillation catheters 2A and 2B shown in FIG. 18 differ from the defibrillation catheters 2A and 2B shown in FIG. 16 mainly in the shape of the lumen tube 29 and the configuration of the handle 28.

In this modified example, the lumen tube 29 is disposed within the tube 21 and extends from the outer circumferential surface of the tube 21 to the tip 21a. Specifically, the lumen tube 29 extends obliquely from the outer circumferential surface of the tube 21 to the central axis of the tube 21, and further extends along the central axis to the tip of the distal tip 26. This defibrillation catheter 2A, 2B is also called a rapid exchange type.

The handle 28 includes a main body 28a and a strain relief 28c. The main body 28a also functions as a connector and includes a connector pin. Each lead wire 24a and each lead wire 25a are connected to the connector pin of the main body 28a.

Even with this configuration, the defibrillation catheters 2A, 2B can be moved along the guide wire 31 while the guide wire 31 is inserted into the blood vessel to reach the affected area. This simplifies the insertion of the defibrillation catheters 2A, 2B. Furthermore, with this configuration, when replacing the defibrillation catheters 2A, 2B with spare defibrillation catheters 2A, 2B, the length of the guide wire 31 protruding from the patient P can be made shorter compared to the over-the-wire type.

As shown in FIG. 19, the defibrillation catheters 2A and 2B may further include a balloon 30. FIG. 19 is a schematic diagram of a defibrillation catheter of yet another modified example. The defibrillation catheters 2A and 2B shown in FIG. 19 differ from the defibrillation catheters 2A and 2B shown in FIG. 16 mainly in that they further include a balloon 30, the use of the lumen tube 29, and the configuration of the handle 28.

In this modification, the lumen tube 29 is used as a supply tube for supplying fluid to the balloon 30. The fluid may be a gas or a liquid such as saline or contrast medium.

The material of the lumen tube 29 may be a flexible fluororesin. Examples of such materials include highly insulating materials such as perfluoroalkylvinylether copolymer (PFA) and polytetrafluoroethylene (PTFE). The lumen tube 29 may be made of an antithrombotic material produced by blending antithrombotic substances such as heparin, prostaglandin, urokinase, and arginine derivatives with these materials.

The balloon 30 is a member that can be inflated (expanded) and contracted. The balloon 30 can be inflated, for example, into a spherical shape. The balloon 30 is provided at the tip 21a of the tube 21. Specifically, the balloon 30 is attached to the tip tip 26. When fluid is supplied into the balloon 30 via the lumen tube 29, the volume of the balloon 30 increases and the balloon 30 expands. When fluid is discharged from the balloon 30 via the lumen tube 29, the volume of the balloon 30 decreases and the balloon 30 contracts.

The balloon 30 is made of a material that has a certain degree of flexibility. Examples of such materials include polyolefins such as polyethylene, polypropylene, and ethylene-propylene copolymers; polyesters such as polyethylene terephthalate; thermoplastic resins such as polyvinyl chloride, ethylene-vinyl acetate copolymers, crosslinked ethylene-vinyl acetate copolymers, and polyurethanes; polyamides; polyamide elastomers; silicone rubber; and latex rubber. The balloon 30 may have a single-layer structure or a laminate structure of two or more layers. The outer surface of the balloon 30 may be coated with a substance having antithrombotic properties.

The handle 28 differs from the handle 28 of the defibrillation catheters 2A and 2B shown in FIG. 16 mainly in that it further includes a hub 28e and in the arrangement of the connector 28d. The hub 28e is a member located at the end of the lumen tube 29. Examples of materials that can be used to form the hub 28e include thermoplastic resins such as polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-styrene copolymer. The connector 28d is disposed in parallel with the hub 28e. In other words, the connector 28d is disposed at a position that is offset from the central axis of the tube 21.

The defibrillation catheters 2A and 2B are inserted into the blood vessels of the patient P with the balloon 30 deflated and wrapped around the outer surface of the tube 21. When the balloon 30 is expanded by supplying fluid to the balloon 30 with the defibrillation catheters 2A and 2B inserted into the blood vessel, the balloon 30 receives force from the blood flowing through the blood vessel. This allows the defibrillation catheters 2A and 2B to move forward with the flow of blood, simplifying the insertion of the defibrillation catheters 2A and 2B.

In the above embodiment, the defibrillation catheters 2A and 2B are single-lumen catheters, but may be multi-lumen catheters. For example, the defibrillation catheters 2A and 2B may further include at least one of a lumen tube through which the lead wire group 24 extends, a lumen tube through which the lead wire group 25 extends, and a lumen tube through which the pull wire 27 extends. In this case, the defibrillation catheters 2A and 2B may further include a core filled between each lumen tube and the tube 21. The core is made of, for example, a low-hardness nylon elastomer. Furthermore, the defibrillation catheters 2A and 2B may include a blade provided between the tube 21 and the core instead of the blade 21c. Note that the blade may not be provided in the region of the tube 21 where the electrode group 22 is provided.

(Additional Note)
[1]
a first defibrillation catheter for performing defibrillation in a cardiac chamber, the first defibrillation catheter having a first electrode group including a plurality of first electrodes;
a second defibrillation catheter for performing defibrillation in a cardiac chamber, the second defibrillation catheter having a second electrode group including a plurality of second electrodes;
a defibrillator having a first connector for connecting the first defibrillation catheter, a second connector for connecting the second defibrillation catheter, and a power supply circuit for supplying a voltage;
Equipped with
The defibrillator applies voltages of the same polarity to the first electrodes and applies voltages of the same polarity to the second electrodes.

[2]
The defibrillator applies a voltage having a polarity different from a polarity of a voltage applied to the plurality of first electrodes to the plurality of second electrodes.

[3]
Further comprising a return electrode for performing defibrillation on the body surface;
The defibrillator further includes a third connector for connecting the return electrode.
The intracardiac defibrillation system according to claim 1 or 2, wherein the defibrillator applies to the return electrode a voltage having a polarity different from a polarity of a voltage applied to the plurality of first electrodes or the plurality of second electrodes.

[4]
The intracardiac defibrillation system according to [3], wherein the defibrillator further has a switching circuit capable of selectively switching between a first member of the first electrode group, the second electrode group, and the return electrode plate, the first member being connected to a first terminal of the power supply circuit, and a second member being connected to a second terminal of the power supply circuit.

[5]
The defibrillator further includes a measuring device for measuring a resistance value of a path through which the voltage is supplied,
The intracardiac defibrillation system according to claim 4, wherein the switching circuit selectively connects the first member and the second member to either the power supply circuit or the measuring device.

[6]
Further comprising an electrocardiograph;
the first defibrillation catheter further includes a third electrode group including a plurality of third electrodes;
the second defibrillation catheter further includes a fourth electrode group including a plurality of fourth electrodes;
The intracardiac defibrillation system according to any one of [1] to [5], wherein the electrocardiograph measures the potentials of the plurality of third electrodes and the potentials of the plurality of fourth electrodes.

[7]
The defibrillator further includes a measuring device for measuring a resistance value of a path through which the voltage is supplied, and a calculation processing unit for controlling the power supply circuit,
The intracardiac defibrillation system according to any one of [1] to [6], wherein the calculation processing unit applies a voltage to the power supply circuit when the resistance value is within an appropriate range.

[8]
The intracardiac defibrillation system according to claim 7, wherein the calculation processing unit applies a voltage to the power supply circuit in synchronization with a peak of an intracardiac potential.

[9]
the first defibrillation catheter further comprises a tubular member;
Each of the plurality of first electrodes is provided on an outer circumferential surface of the tubular member,
The intracardiac defibrillation system according to any one of [1] to [8], wherein the plurality of first electrodes are arranged in the axial direction of the tubular member.

[10]
The first defibrillation catheter
A tip provided at the tip of the tubular member;
a pull wire disposed within the tubular member and having one end fixed to the distal tip at a position eccentric to a central axis of the tubular member;
an operation unit that advances and retreats the pull wire in the axial direction;
The intracardiac defibrillation system according to [9], further comprising:

[11]
The first defibrillation catheter
a balloon provided at a tip of the tubular member and capable of expanding and contracting;
a supply tube for supplying fluid to the balloon;
The intracardiac defibrillation system according to [9], further comprising:

[12]
The intracardiac defibrillation system of [9], wherein the first defibrillation catheter further has an insertion tube for inserting a guide wire, the insertion tube being disposed within the tubular member and extending from the base end of the tubular member to the tip end of the tubular member.

[13]
The intracardiac defibrillation system of [9], wherein the first defibrillation catheter further has an insertion tube for inserting a guide wire, the insertion tube being disposed within the tubular member and extending from the outer circumferential surface to the tip of the tubular member.

[14]
The intracardiac defibrillation system according to any one of [9] to [13], wherein each of the plurality of first electrodes has a convex curved shape in a direction intersecting with the axial direction.

[15]
The intracardiac defibrillation system according to any one of [9] to [14], wherein the first defibrillation catheter further has an insulating member filling a recess defined by an end face in the axial direction and the outer circumferential surface of one of the plurality of first electrodes.

1...Intracardiac defibrillation system, 2A...Defibrillation catheter (first defibrillation catheter), 2B...Defibrillation catheter (second defibrillation catheter), 3...Return electrode, 4...Electrocardiograph, 10...Defibrillation device, 10a...Connector (first connector), 10b...Connector (second connector), 10c...Connector (third connector), 12...Power supply circuit, 12a...Output terminal (first terminal), 12b...Output terminal (second terminal), 13...Measuring device, 14...Switching circuit, 15... Processing unit, 21...tube (tubular member), 22...electrode group (first electrode group, second electrode group), 22a...electrode (first electrode, second electrode), 22s...recess, 23...electrode group (third electrode group, fourth electrode group), 23a...electrode (third electrode, fourth electrode), 26...tip, 27...pull wire, 28b...operation lever (operation unit), 29...lumen tube (supply tube, insertion tube), 30...balloon, 31...guide wire, G...glue (insulating member).

Claims (21)

An intracardiac defibrillation system for performing electrical defibrillation during surgery, comprising:
a first defibrillation catheter for performing defibrillation in a cardiac chamber, the first defibrillation catheter comprising: a first electrode group including a plurality of first electrodes; a first handle used for operating the first defibrillation catheter ; a tubular member; a distal tip provided at the distal end of the tubular member; a pull wire disposed within the tubular member, the pull wire having one end fixed to the distal tip at a position eccentric to a central axis of the tubular member; and an operation section for advancing and retracting the pull wire in the axial direction of the tubular member;
a second defibrillation catheter for performing defibrillation in a cardiac chamber, the second defibrillation catheter having a second electrode group including a plurality of second electrodes and a second handle used to operate the second defibrillation catheter;
a defibrillator having a first connector for connecting the first defibrillation catheter, a second connector for connecting the second defibrillation catheter, and a power supply circuit for supplying a voltage;
Equipped with
Each of the plurality of first electrodes is provided on an outer circumferential surface of the tubular member,
The plurality of first electrodes are arranged in the axial direction,
The defibrillator applies voltages of the same polarity to the first electrodes and applies voltages of the same polarity to the second electrodes. An intracardiac defibrillation system for performing electrical defibrillation during surgery, comprising:
A first defibrillation catheter for performing defibrillation in a cardiac chamber, the first defibrillation catheter having a first electrode group including a plurality of first electrodes, a tubular member, a first lead wire group including a plurality of first lead wires, and a lumen tube through which the first lead wire group extends;
a second defibrillation catheter for performing defibrillation in a cardiac chamber, the second defibrillation catheter having a second electrode group including a plurality of second electrodes;
a defibrillator having a first connector for connecting the first defibrillation catheter, a second connector for connecting the second defibrillation catheter, and a power supply circuit for supplying a voltage;
Equipped with
Each of the plurality of first electrodes is provided on an outer circumferential surface of the tubular member,
The plurality of first electrodes are arranged in an axial direction of the tubular member,
the lumen tube is disposed within the tubular member;
the first lead wires electrically connect the first electrodes to the first connector;
The defibrillator applies voltages of the same polarity to the first electrodes and applies voltages of the same polarity to the second electrodes. 3. The intracardiac defibrillation system of claim 2, wherein the defibrillator applies a voltage of a polarity to the second electrodes that is different from a polarity of a voltage applied to the first electrodes. An electrocardiograph,
a switching circuit that selectively switches a connection destination of the first electrode group and a connection destination of the second electrode group;
Further comprising:
the switching circuit is capable of selectively switching between a state in which the first electrode group is connected to the power supply circuit and a state in which the first electrode group is connected to the electrocardiograph,
the switching circuit is capable of selectively switching between a state in which the second electrode group is connected to the power supply circuit and a state in which the second electrode group is connected to the electrocardiograph,
The intracardiac defibrillation system of claim 2 , wherein the electrocardiograph measures electrical potentials of the first plurality of electrodes and electrical potentials of the second plurality of electrodes. Further comprising an electrocardiograph;
the first defibrillation catheter further includes a third electrode group including a plurality of third electrodes;
the second defibrillation catheter further includes a fourth electrode group including a plurality of fourth electrodes;
The intracardiac defibrillation system of claim 2 , wherein the electrocardiograph measures electrical potentials of the plurality of third electrodes and electrical potentials of the plurality of fourth electrodes. An electrocardiograph,
a switching circuit that selectively switches a connection destination of the first electrode group and a connection destination of the second electrode group;
Further comprising:
the switching circuit is capable of selectively switching between a state in which the first electrode group is connected to the power supply circuit and a state in which the first electrode group is connected to the electrocardiograph,
the switching circuit is capable of selectively switching between a state in which the second electrode group is connected to the power supply circuit and a state in which the second electrode group is connected to the electrocardiograph,
the first defibrillation catheter further includes a third electrode group including a plurality of third electrodes;
the second defibrillation catheter further includes a fourth electrode group including a plurality of fourth electrodes;
3. The intracardiac defibrillation system of claim 2, wherein the electrocardiograph measures electrical potentials of the first electrodes, the second electrodes, the third electrodes, and the fourth electrodes. 3. The intracardiac defibrillation system according to claim 2, further comprising a switching circuit capable of selectively switching between a first member of the first electrode group and a second member of the second electrode group, the first member being connected to a first terminal of the power supply circuit and a second member being connected to a second terminal of the power supply circuit. Further comprising a return electrode for performing defibrillation on the body surface;
The defibrillator further includes a third connector for connecting the return electrode.
3. The intracardiac defibrillation system of claim 2, wherein the defibrillator applies a voltage to the return electrode plate having a polarity different from a polarity of a voltage applied to the first electrodes or the second electrodes. The intracardiac defibrillation system according to claim 8, further comprising a switching circuit that selectively switches between a first member of the first electrode group, the second electrode group, and the return electrode plate that is connected to a first terminal of the power supply circuit and a second member of the first electrode group, the second electrode group, and the return electrode plate that is connected to a second terminal of the power supply circuit. The defibrillator further includes a measuring device for measuring a resistance value of a path through which the voltage is supplied,
10. The intracardiac defibrillation system of claim 9, wherein the switching circuit selectively connects the first member and the second member to either the power supply circuit or the measuring device. The defibrillator further includes a measuring device for measuring a resistance value of a path through which the voltage is supplied, and a calculation processing unit for controlling the power supply circuit,
The intracardiac defibrillation system according to claim 2 , wherein the arithmetic processing unit applies a voltage to the power supply circuit when the resistance value is within an appropriate range. The intracardiac defibrillation system according to claim 11, wherein the arithmetic processing unit applies a voltage to the power supply circuit in synchronization with a peak of the intracardiac potential. The intracardiac defibrillation system according to claim 2 , wherein the first defibrillation catheter further comprises a leaf spring for planarly deflecting the distal end of the tubular member. the first defibrillation catheter further comprises a lumen tube through which the pull wire extends;
The intracardiac defibrillation system of claim 1 , wherein the lumen tube is disposed within the tubular member. The first defibrillation catheter
A tip provided at the tip of the tubular member;
a pull wire disposed within the tubular member and having one end fixed to the distal tip at a position eccentric to a central axis of the tubular member;
an operation unit that advances and retreats the pull wire in the axial direction;
3. The intracardiac defibrillation system of claim 2, further comprising: the first defibrillation catheter further comprises another lumen tube through which the pull wire extends;
16. The intracardiac defibrillation system of claim 15 , wherein the additional lumen tube is disposed within the tubular member. The first defibrillation catheter
a balloon provided at a tip of the tubular member and capable of expanding and contracting;
a supply tube for supplying fluid to the balloon;
3. The intracardiac defibrillation system of claim 2 , further comprising: 3. The intracardiac defibrillation system according to claim 2, wherein the first defibrillation catheter further includes an insertion tube for inserting a guide wire, the insertion tube being disposed within the tubular member and extending from a base end of the tubular member to a tip end of the tubular member. 3. The intracardiac defibrillation system according to claim 2 , wherein the first defibrillation catheter further includes an insertion tube for inserting a guide wire, the insertion tube being disposed within the tubular member and extending from the outer circumferential surface to the tip of the tubular member. The intracardiac defibrillation system according to claim 2 , wherein each of the plurality of first electrodes has a convex curved shape in a direction intersecting with the axial direction. 3. The intracardiac defibrillation system according to claim 2, wherein the first defibrillation catheter further includes an insulating member filling a recess defined by an end surface in the axial direction and the outer circumferential surface of one of the plurality of first electrodes.

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