Power supply device and ablation system

Abstract

To efficiently supply high voltage pulses to a plurality of electrodes of a catheter.SOLUTION: A power supply device 14 supplies a pulse voltage to a plurality of electrodes of a catheter 12. The power supply device 14 comprises: a pulse generation circuit 42 which generates a pulse voltage by switching a DC voltage; and an output switch circuit 44 which is connected between the pulse generation circuit 42 and the plurality of electrodes and switches an electrode to which the pulse voltage is outputted.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a power supply and an ablation system. [Background technology]

[0002] Ablation therapy involves inserting an electrode catheter into the patient's body and applying high-frequency current to cauterize tissue. Recently, ablation systems using electroporation, which applies high-voltage pulses, have been proposed as a non-thermal treatment method. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2019-500170 Summary of the Invention [Problem to be solved by the invention]

[0004] Electroporation requires a power supply that efficiently delivers high voltage pulses to the multiple electrodes of the catheter.

[0005] The present disclosure has been made in view of the above circumstances, and one of its objectives is to provide a power supply device that can efficiently supply high voltage pulses to multiple electrodes of a catheter. [Means for solving the problem]

[0006] A power supply device according to one aspect of the present disclosure supplies pulse voltages to multiple electrodes of a catheter, and includes a pulse generation circuit that generates the pulse voltages by switching a DC voltage, and an output switching circuit that is connected between the pulse generation circuit and the multiple electrodes and that switches the electrodes to which the pulse voltage is output.

[0007] An ablation system according to one aspect of the present disclosure includes a catheter having a plurality of electrodes, a return electrode, and a power supply that supplies a pulse voltage between at least one of the plurality of electrodes and the return electrode. The power supply includes a pulse generation circuit that switches a DC voltage to generate the pulse voltage, and an output switching circuit that is connected between the pulse generation circuit and the plurality of electrodes and that switches the electrode to which the pulse voltage is output.

[0008] Any combination of the above components, and conversion of the expression of the present disclosure into a method, device, system, etc., are also valid aspects of the present disclosure. [Effects of the Invention]

[0009] According to the present disclosure, a power supply device capable of efficiently supplying high voltage pulses to multiple electrodes of a catheter can be provided. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a diagram schematically illustrating an ablation system according to an embodiment. [Figure 2] FIG. 1 is a perspective view showing an example of the configuration of an electrode assembly of a catheter. [Figure 3] 1 is a diagram schematically illustrating a circuit configuration of a power supply device according to a first embodiment. [Figure 4] 4(a) and 4(b) are diagrams showing an example of an output voltage waveform of a pulse generating circuit. [Figure 5] 4 is a timing chart schematically showing a first operation example of the output switching circuit. [Figure 6] 10 is a timing chart schematically illustrating a second operation example of the output switching circuit. [Figure 7] FIG. 10 is a circuit diagram schematically illustrating the configuration of a power supply device according to a second embodiment. [Figure 8] 10 is a timing chart schematically illustrating an example of the operation of the output switching circuit. [Figure 9] FIG. 10 is a circuit diagram schematically illustrating the configuration of a power supply device according to a third embodiment. [Figure 10] FIG. 10 is a circuit diagram schematically showing the configuration of a power supply device according to a fourth embodiment. [Figure 11] FIG. 2 is a diagram illustrating an example of an output voltage waveform of a pulse generating circuit. [Figure 12] FIG. 10 is a circuit diagram schematically showing the configuration of a power supply device according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present disclosure will be described below with reference to preferred embodiments and drawings. The embodiments are illustrative and do not limit the present disclosure, and all features and combinations thereof described in the embodiments are not necessarily essential to the present disclosure. The same or equivalent components, parts, and processes shown in each drawing are designated by the same reference numerals, and redundant descriptions will be omitted where appropriate. The scale and shape of each part shown in each drawing are set for convenience to facilitate explanation and should not be interpreted as limiting unless otherwise specified. Furthermore, when terms such as "first" and "second" are used in this specification or claims, unless otherwise specified, these terms do not indicate any order or importance, but are intended to distinguish one configuration from another. Furthermore, some components that are not important for explaining the embodiments are omitted from each drawing.

[0012] 1 is a diagram schematically illustrating an ablation system 10 according to an embodiment. The ablation system 10 includes a catheter 12, a power supply 14, and a return electrode 16. The ablation system 10 may further include a measurement device 18.

[0013] 1 depicts some of the components of the ablation system 10 as functional blocks. At least some of these functional blocks can be realized as a hardware configuration using elements and circuits such as a computer CPU and memory, or as a software configuration using a computer program, etc. Those skilled in the art will understand that these functional blocks can be realized in various ways by combining hardware and software.

[0014] The ablation system 10 ablates tissue in an affected area 22 of a patient 20. The ablation system 10 ablates the affected area 22 using irreversible electroporation (IRE). IRE involves pulsed electric field ablation (PFA). PFA is an ablation technique that kills cells in the affected area 22 using a pulsed electric field generated by applying a high voltage between the catheter 12 and the return electrode 16, forming a lesion in the affected area 22. Because IRE is non-thermal, it can minimize damage to tissues and nerves surrounding the affected area 22.

[0015] The affected area 22 to be ablated may be, for example, a heart experiencing arrhythmia. For example, when performing pulmonary vein isolation to treat atrial fibrillation, damage to the esophagus and phrenic nerve surrounding the affected area can be prevented, thereby preventing complications such as esophageal fistula and phrenic nerve paralysis. The ablation system 10 can also be used for ablation of other organs and tissues.

[0016] The catheter 12 includes an electrode assembly 24, a shaft 26, and a handle 28. The electrode assembly 24 is provided on the distal end side of the shaft 26 and has a plurality of electrodes. The electrode assembly 24 is inserted into the body when the catheter 12 is in use.

[0017] The shaft 26 is made of a flexible tubular body. The shaft 26 is made of a known flexible material, including resins such as polyolefin, polytetrafluoroethylene, polyether block amide, and polyamide. The shaft 26 has, for example, a multi-lumen structure having multiple lumens. Various thin wires (not shown), such as lead wires and operating wires, and an inner tube 34 (see FIG. 2), which will be described later, are inserted into the lumens.

[0018] The handle 28 is provided on the proximal side of the shaft 26. The handle 28 is disposed outside the body when the catheter 12 is in use, and is grasped and operated by the operator. The handle 28 includes a main body portion grasped by the operator and an operating portion for advancing and retracting the inner tube 34. When the operating portion is operated to displace the inner tube 34 toward the proximal side relative to the shaft 26, the electrode assembly 24, which is in a collapsed state, unfolds in a direction away from the axis of the shaft 26. When the operating portion is operated to displace the inner tube 34 toward the distal side relative to the shaft 26, the electrode assembly 24, which is in an unfolded state, unfolds.

[0019] Figure 2 is a perspective view showing an example configuration of the electrode assembly 24 of the catheter 12. The electrode assembly 24 includes a plurality of splines 36a, 36b, 36c, 36d, 36e, and 36f (collectively referred to as splines 36) and a plurality of electrodes 38a1, 38a2, 38a3, 38a4, 38b1, 38b2, 38b3, 38b4, 38c1, 38c2, 38c3, 38c4, 38d1, 38d2, 38d3, 38d4, 38e1, 38e2, 38e3, 38e4, 38f1, 38f2, 38f3, and 38f4 (collectively referred to as electrodes 38). Figure 2 shows the splines 36 in an expanded state.

[0020] The plurality of splines 36 are linear bodies extending in the axial direction of the shaft 26 and are made of the same flexible material as the shaft 26. As an example, the plurality of splines 36 may include six splines, namely a first spline 36a, a second spline 36b, a third spline 36c, a fourth spline 36d, a fifth spline 36e, and a sixth spline 36f. The number of the plurality of splines 36 is not limited to six, and may be five or less, or seven or more.

[0021] The multiple splines 36 are arranged at intervals around the axis of the shaft 26. The distal ends of the multiple splines 36 are fixed to the distal tip 32. The proximal ends of the multiple splines 36 are inserted into the shaft 26 from its distal end and fixed to the shaft 26. The distal tip 32 is fixed to the distal end of the inner tube 34. The inner tube 34 is passed through the lumen of the shaft 26. The proximal end side of the inner tube 34 is connected to the handle 28. The distal tip 32 and the inner tube 34 can be displaced distally or proximally relative to the shaft 26 by operating the handle 28.

[0022] When the inner tube 34 is retracted toward the proximal end of the shaft 26 with the splines 36 extending linearly, the distal tip 32 is displaced toward the distal end of the shaft 26. This causes each spline 36 to curve and bulge outward, and the electrode assembly 24 unfolds into a basket shape. When the inner tube 34 is pushed toward the distal end of the shaft 26 with the splines 36 curved, the distal tip 32 is displaced away from the distal end of the shaft 26. This causes the splines 36 to straighten, and the electrode assembly 24 is folded.

[0023] A plurality of electrodes 38 are provided on the plurality of splines 36. The plurality of electrodes 38 are arranged at predetermined intervals along the longitudinal direction of each spline 36. Each electrode 38 is ring-shaped and made of a metal with good electrical conductivity, such as platinum, gold, silver, copper, aluminum, or stainless steel, or an alloy thereof. The same number of electrodes 38 are provided on each of the splines 36a to 36f. For example, four electrodes 38 are provided on each of the splines 36i (i=a to f). A first electrode 38i1, a second electrode 38i2, a third electrode 38i3, and a fourth electrode 38i4 are provided on each of the splines 36i. For example, a first electrode 38a1, a second electrode 38a2, a third electrode 38a3, and a fourth electrode 38a4 are provided on the first spline 36a. The same applies to the second to sixth splines 36b to 36f. The number of electrodes 38 provided on each spline 36 is not limited to four, but may be three or less, or five or more.

[0024] The tip of a conductor (not shown) is connected to each electrode 38. The conductor connected to each electrode 38 is passed through a lumen of the shaft 26. The proximal end of the conductor connected to each electrode 38 is connected to a connector (not shown) of the handle 28. The conductor connected to each electrode 38 is electrically connected to the power supply 14 via a cable 30 that is connected to the connector of the handle 28. A pulse voltage is applied to the multiple electrodes 38 by the power supply 14, as will be described in detail below.

[0025] Returning to FIG. 1 , the return electrode 16 is placed on the body surface of the patient 20 during ablation. The return electrode 16 is electrically connected to the power supply 14. The power supply 14 applies a pulse voltage between the electrode 38 of the catheter 12 and the return electrode 16. The application of the pulse voltage causes ablation of the affected area 22 of the patient 20.

[0026] The power supply device 14 includes a DC power supply 40, a pulse generating circuit 42, an output switching circuit 44, and a control unit 46. The DC power supply 40 outputs a predetermined DC voltage. The DC power supply 40 includes a DC-DC converter such as a switching regulator, and an output capacitor. The output voltage of the DC power supply 40 is not particularly limited, but is, for example, 1 kV or 2 kV or more, and is, for example, 4 kV or less or 3 kV or less.

[0027] The pulse generating circuit 42 generates a pulse voltage by switching the DC voltage output from the DC power supply 40. The pulse generating circuit 42 includes a bridge circuit using semiconductor switches such as field effect transistors (FETs) and insulated gate bipolar transistors (IGBTs). The pulse generating circuit 42 includes, for example, a first bridge circuit connected to the output switching circuit 44 and a second bridge circuit connected to the return electrode 16.

[0028] The output switching circuit 44 switches the electrodes 38 to which the pulse voltage generated by the pulse generating circuit 42 is output. The output switching circuit 44 includes a plurality of switches connected in parallel between the pulse generating circuit 42 and the plurality of electrodes 38a1 to 38f4. The plurality of switches are configured using mechanical switches having mechanical contacts, such as mechanical relays. Each of the plurality of switches is connected to at least one electrode 38 among the plurality of electrodes 38a1 to 38f4. Each of the plurality of switches may be connected to at least one electrode 38 provided on each spline 36 among the plurality of splines 36a to 36f. Each of the plurality of switches may be connected to two or more electrodes 38 provided on each spline 36 among the plurality of splines 36a to 36f. Each of the plurality of switches may be connected to a respective electrode 38 provided on each spline 36 among the plurality of splines 36a to 36f.

[0029] The output switching circuit 44 allows at least one electrode 38 of the catheter 12 to be connected to the measuring device 18. The measuring device 18 can use at least one electrode 38 of the plurality of electrodes 38a1 to 38f4 as a measurement terminal. The measuring device 18 may be, for example, an electrocardiograph that measures cardiac potentials using at least one electrode 38. The measuring device 18 may also be an impedance measuring device that measures the impedance between at least one electrode 38 and an indifferent electrode. The indifferent electrode may be at least one electrode 38 provided in the electrode assembly 24, an electrode provided at a position separate from the electrode assembly 24, or an electrode provided in an electrode catheter separate from the catheter 12.

[0030] The control unit 46 controls the overall operation of the power supply device 14. The control unit 46 is configured using an integrated circuit such as an FPGA (Field Programmable Gate Array). The control unit 46 controls the operation of the DC power supply 40 and variably controls the output voltage of the DC power supply 40. The control unit 46 controls the operation of the pulse generation circuit 42 and controls the pulse width, period, number of repetitions, etc. of the pulse voltage generated by the pulse generation circuit 42. The control unit 46 controls the operation of the output switching circuit 44 and switches the electrode 38 to which the pulse voltage is output.

[0031] The control unit 46 may be realized by hardware (circuitry), software (programs), or a combination of these. When realized by software, the software is composed of a group of programs for causing a computer to execute each function. Each program may be pre-installed in the computer, or may be installed into the computer from a network or recording medium, for example.

[0032] A specific circuit configuration of the power supply device 14 will now be described.

[0033] (First embodiment) 3 is a diagram schematically illustrating the circuit configuration of the power supply device 14 according to the first embodiment. The pulse generating circuit 42 includes a first bridge circuit 50 and a second bridge circuit 52. The first bridge circuit 50 is connected to the output switching circuit 44. The second bridge circuit 52 is connected to the return electrode 16. The first bridge circuit 50 and the second bridge circuit 52 form a full bridge circuit for outputting a pulse voltage to a load between the electrode 38 of the catheter 12 and the return electrode 16.

[0034] The first bridge circuit 50 includes an upper arm 54 and a lower arm 56. The upper arm 54 is connected between the positive electrode of the DC power supply 40 and an output 58 of the first bridge circuit 50. The lower arm 56 is connected between the negative electrode of the DC power supply 40 and the output 58 of the first bridge circuit 50. The upper arm 54 and the lower arm 56 are configured by semiconductor switches such as FETs or IGBTs. The upper arm 54 and the lower arm 56 are switched between an ON state and an OFF state by, for example, a gate signal from a gate drive circuit (not shown) controlled by the control unit 46. The switching time of the semiconductor switch is, for example, 1 μs or less, e.g., 0.1 μs or less. The second bridge circuit 52 can be configured similarly to the first bridge circuit 50.

[0035] The switching time of a semiconductor switch is the so-called turn-on time t on or turn-off time t offAlternatively, the time may be the time from when the gate signal (e.g., gate-source voltage) starts to rise or fall until the output voltage (e.g., drain-source voltage) of the semiconductor switch reaches a predetermined value. The gate signal starts to rise when it rises to 10% of the set value. The gate signal starts to fall when it drops to 90% of the set value (i.e., drops by 10% of the set value). Furthermore, the time when the semiconductor switch is turned on and the output voltage reaches a predetermined value may be the time when the output voltage rises to 90% of the set voltage. Furthermore, the time when the semiconductor switch is turned off and the output voltage reaches a predetermined value may be the time when the output voltage drops to 10% of the set voltage.

[0036] The pulse generating circuit 42 turns on the upper arm 54 of the first bridge circuit 50 and the lower arm of the second bridge circuit 52, thereby generating a pulse voltage (also referred to as a positive voltage phase pulse) that causes the electrode 38 of the catheter 12 to have a positive voltage with respect to the return electrode 16. The pulse generating circuit 42 turns on the lower arm 56 of the first bridge circuit 50 and the upper arm of the second bridge circuit 52, thereby generating a pulse voltage (also referred to as a negative voltage phase pulse) that causes the electrode 38 of the catheter 12 to have a negative voltage with respect to the return electrode 16. The pulse generating circuit 42 stops generating the pulse voltage by turning off the first bridge circuit 50 and the second bridge circuit 52.

[0037] The output switching circuit 44 includes a plurality of output switches 60a1-60f4 (collectively referred to as output switches 60). The plurality of output switches 60a1-60f4 are connected in parallel between the pulse generating circuit 42 and the plurality of electrodes 38a1-38f4 of the catheter 12. Each of the output switches 60a1-60f4 is connected to at least one electrode 38 among the plurality of electrodes 38a1-38f4. In the example shown in FIG. 3, each of the output switches 60a1-60f4 is connected to a respective electrode 38a1-60f4. Therefore, the number of the plurality of output switches 60a1-60f4 is the same as the number of the plurality of electrodes 38a1-38f4 of the catheter 12, e.g., 24.

[0038] Each of the output switches 60a1 to 60f4 has a first contact 62 connected to the pulse generating circuit 42 and a second contact 64 connected to each of the electrodes 38a1 to 38f4. The output switch 60 switches between a connection state in which the first contact 62 and the second contact 64 are connected and a disconnection state in which the first contact 62 and the second contact 64 are disconnected. The output switch 60 can be configured by a mechanical relay. The output switch 60 switches between the connection state and the disconnection state in response to a control signal output from the control unit 46. The switching time of the output switch 60 is, for example, 1 ms or more or 2 ms or more, and, for example, 10 ms or less or 5 ms or less. The switching time of the output switch 60 is significantly longer than the switching time of a semiconductor switch.

[0039] The switching time of a mechanical switch may be the sum of the operating time or release time and the bounce time. The operating time is the time from when the control signal is turned on (for example, when the coil starts to be energized) until the contacts are connected or disconnected. The release time is the time from when the control signal is turned off (for example, when the coil is no longer energized) until the contacts are connected or disconnected. The bounce time is the time from when the control signal is turned on or off to switch the state of the contacts until the intermittent opening and closing phenomenon (fluttering) between the contacts, which occurs when the contacts collide with each other, subsides.

[0040] Each of the output switches 60a1 to 60f4 may be an a-contact relay, a b-contact relay, or a c-contact relay. An a-contact relay is a so-called normally open type, in which the movable contact contacts the fixed contact to establish a connection state when the coil is energized, and the movable contact separates from the fixed contact to establish a disconnection state when the coil is not energized. A b-contact relay is a so-called normally closed type, in which the movable contact contacts the fixed contact to establish a connection state when the coil is not energized, and the movable contact separates from the fixed contact to establish a disconnection state when the coil is energized. A c-contact relay is a so-called transfer type. In a c-contact relay, when the coil is energized, the movable contact contacts the a-contact to establish a connection state with the a-contact, and separates from the b-contact to establish a disconnection state with the b-contact. In a c-contact relay, when the coil is not energized, the movable contact separates from the a-contact to establish a disconnection state with the a-contact, and contacts the b-contact to establish a connection state with the b-contact.

[0041] The output switching circuit 44 may further include a measurement switch 70. The measurement switch 70 has a third contact 72 connected to the first contacts 62 of the plurality of output switches 60a1 to 60f4, and a fourth contact 74 connected to the measuring device 18. The measurement switch 70 may be configured by a mechanical relay. Like the output switch 60, the measurement switch 70 is switched between a connected state and a disconnected state by a control signal output from the control unit 46. The measurement switch 70 may be the above-mentioned a-contact relay, a b-contact relay, or a c-contact relay.

[0042] The control unit 46 operates the power supply device 14 in either an output mode or a measurement mode. In the output mode, a pulse voltage is generated by the pulse generating circuit 42, and the electrodes 38a1-38f4 to which the pulse voltage is output are switched by the multiple output switches 60a1-60f4. In the output mode, the measurement switch 70 is in a cut-off state. In the measurement mode, the measurement switch 70 is in a connect state, and the electrodes 38a1-38f4 connected to the measuring device 18 are switched by the multiple output switches 60a1-60f4. In the measurement mode, the pulse generating circuit 42 is turned off, and generation of the pulse voltage is stopped.

[0043] 4(a) and 4(b) are diagrams schematically showing an example of an output voltage waveform of the pulse generating circuit 42. 4(a) and 4(b) show the output voltage of the first bridge circuit 50 when the output of the second bridge circuit 52 is set as a reference (0 V). The amplitude Va of the pulse voltage corresponds to the output voltage of the DC power supply 40 and is, for example, 1 kV or 2 kV or more, and, for example, 4 kV or less or 3 kV or less.

[0044] FIG. 4(a) shows the output voltage waveform during a basic period T for performing ablation. The basic period T includes an output period T1 during which the pulse voltage group 100 is output and a stop period T2 during which the output of the pulse voltage is stopped. The output period T1 and the stop period T2 are repeated alternately. The number of output periods T1 included in the basic period T is not particularly limited, but is, for example, 2 to 100 times. The number of output periods T1 included in the basic period T may be the same as the number of switching of the output destination electrodes 38a1 to 38f4, for example, 24 times. The duration of one output period T1 is, for example, 0.1 ms or more or 0.5 ms or more, and, for example, 10 ms or less or 5 ms or less. The duration of one stop period T2 is, for example, 3 ms or more or 5 ms or more, and, for example, 20 ms or less or 15 ms or less. The duration of the stop period T2 is set to be longer than the switching time of the output switch 60, for example, to be at least two or three times the switching time of the output switch 60.

[0045] FIG. 4(b) shows the output voltage waveform for one output period T1. The output period T1 includes multiple unit periods T3. The number of unit periods T3 included in one output period T1 is not particularly limited, but may be, for example, 2 to 100, e.g., 10, 20, or 50. The unit period T3 is the period during which a biphasic pulse is output. The unit period T3 includes a first pulse period Tp1 during which a positive voltage phase pulse 102 is output, a second pulse period Tp2 during which a negative voltage phase pulse 104 is output, a dead time period Ta between the first pulse period Tp1 and the second pulse period Tp2, and an interval period Tb during which the output of the pulse voltage is stopped. The duration of each of the first pulse period Tp1 and the second pulse period Tp2 is, for example, 0.1 μs or more or 1 μs or more, and, for example, 100 μs or less or 10 μs or less. The time length of the dead time period Ta is, for example, 0.1 μs or more or 1 μs or more, and, for example, 100 μs or less or 10 μs or less. The dead time period Ta may be longer or shorter than the first pulse period Tp1 or the second pulse period Tp2. The time length of the interval period Tb is, for example, 1 μs or more or 10 μs or more, and, for example, 1 ms or less or 100 μs or less. The time length of the interval period Tb is set longer than the first pulse period Tp1, the second pulse period Tp2, or the dead time period Ta. The time length of the interval period Tb may be set longer than the total time (=Tp1+Ta+Tp2) of the first pulse period Tp1, the second pulse period Tp2, and the dead time period Ta.

[0046] When the output period T1 includes N unit periods T3, strictly speaking, the output period T1 may be composed of N first pulse periods Tp1, N dead time periods Ta, N second pulse periods Tp2, and N-1 interval periods Tb. That is, the output period T1 may end immediately after the output of the Nth negative voltage phase pulse 104 and may not include the Nth interval period Tb after the output of the Nth negative voltage phase pulse 104. In this case, T1 may be expressed as T1 = N × (Tp1 + Ta + Tp2) + (N-1) × Tb. Note that the output period T1 may include the Nth interval period Tb, or may be expressed as T1 = N × (Tp1 + Ta + Tp2 + Tb).

[0047] FIG. 5 is a timing chart schematically illustrating a first operation example of the output switching circuit 44. The first operation example illustrated in FIG. 5 illustrates a case in which pulse voltage groups 100 are sequentially output on an electrode-by-electrode basis. During an output period T1 of the first pulse voltage group 100a1 of the basic period T, the output switch 60a1 is connected, and the other output switches 60a2 to 60f4 are disconnected. This causes the pulse voltage group 100a1 to be output to the first electrode 38a1 of the first spline 36a. During an output period T1 of the next pulse voltage group 100a2, the output switch 60a2 is connected, and the other output switches 60a1, 60a3 to 60f4 are disconnected. This causes the pulse voltage group 100a2 to be output to the second electrode 38a2 of the first spline 36a. During the next output period T1, the output switch 60a3 is connected, and the pulse voltage group 100a3 is output to the third electrode 38a3 of the first spline 36a. In the next output period T1, the output switch 60a4 is connected, and a pulse voltage group 100a4 is output to the fourth electrode 38a4 of the first spline 36a. In this manner, the pulse voltage groups 100a1-100a4 are sequentially output to the plurality of electrodes 38a1-38a4 of the first spline 36a.

[0048] During the next output period T1, the output switch 60b1 is connected, and a pulse voltage group 100b1 is output to the first electrode 38b1 of the second spline 36b. During the following output period T1, the output switches 60b2 to 60b4 are sequentially connected, thereby sequentially outputting a pulse voltage group 100 to the electrodes 38b1 to 38b4 of the second spline 36b. Similarly, the pulse voltage groups 100 are sequentially output to the first electrodes 38i1 to 38i4 (i = c to f) of the third spline 36c, the fourth spline 36d, the fifth spline 36e, and the sixth spline 36f. During the final output period T1, the output switch 60f4 is connected, and a pulse voltage group 100f4 is output to the fourth electrode 38f4 of the sixth spline 36f. As a result, pulse voltage group 100 is sequentially output to electrodes 38a1 to 38f4 of catheter 12, completing one basic period T. Therefore, basic period T shown in Fig. 5 can include 24 output periods T1.

[0049] The state of each output switch 60a1-60f4 of the output switching circuit 44 is maintained during the output period T1 during which the pulse voltage group 100 is output, and is changed during the stop period T2 during which the output of the pulse voltages is stopped. That is, the state of each output switch 60a1-60f4 of the output switching circuit 44 is prohibited from being changed during the output period T1 during which the pulse voltage group 100 is output. It is preferable that the state of each switch 60a1-60f4 of the output switching circuit 44 is also prohibited from being changed during a predetermined waiting period ΔT before the start of the output period T1 and after the end of the output period T1. The predetermined waiting period ΔT is preferably longer than the switching time of the output switch 60. The predetermined waiting period ΔT can be, for example, between one-third and one-half of the stop period T2. During the stop period T2, the order of the first timing at which one output switch (e.g., 60a1) is changed from the connected state to the disconnected state and the second timing at which another output switch (e.g., 60a2) is changed from the disconnected state to the connected state is not particularly limited. The second timing may be earlier than the first timing, the first timing may be earlier than the second timing, or the first timing and the second timing may be simultaneous or overlapping.

[0050] FIG. 6 is a timing chart schematically illustrating a second operation example of the output switching circuit 44. The second operation example in FIG. 6 illustrates a case where pulse voltage groups 100 are sequentially output on a spline-by-spline basis. During output period T1 of the first pulse voltage group 100a of the basic period T, the multiple (four) output switches 60a1-60a4 are in the connected state, and the remaining output switches 60b1-60f4 are in the disconnected state. As a result, the pulse voltage group 100a is output to the multiple electrodes 38a1-38a4 of the first spline 36a. During output period T1 of the next pulse voltage group 100b, the multiple (four) output switches 60b1-60b4 are in the connected state, and the remaining output switches 60a1-60a4 and 60c1-60f4 are in the disconnected state. As a result, the pulse voltage group 100b is output to the multiple electrodes 38b1-38b4 of the second spline 36b. Similarly, pulse voltage groups 100c-100f are sequentially output to the third spline 36c, the fourth spline 36d, the fifth spline 36e, and the sixth spline 36f. At this time, the pulse voltage group 100 is simultaneously output to the multiple electrodes 38i1-38i4 included in the same spline 36i. As a result, the pulse voltage group 100 is sequentially output to each of the splines 36a-36f of the catheter 12, and one basic period T is completed. Therefore, the basic period T shown in FIG. 6 can include six output periods T1.

[0051] The basic period T shown in Fig. 5 or 6 may be repeated multiple times in one ablation. The number of times the basic period T is repeated in one ablation is not particularly limited, and can be, for example, 2 or more or 10 or more, or can be, for example, 1000 or less or 100 or less.

[0052] 5 and 6, the state of the output switching circuit 44 is changed in the stop period T2 so that the electrode from which the pulse voltage group 100 is output is different in two output periods T1 sandwiching the stop period T2. In the stop period T2, the output switch 60 connected to the electrode 38 from which the pulse voltage group 100 is output in the output period T1 immediately preceding the stop period T2 is changed from the connected state to the disconnected state. In the stop period T2, the output switch 60 connected to the electrode 38 from which the pulse voltage group 100 is output in the output period T1 immediately following the stop period T2 is changed from the disconnected state to the connected state. Thus, in the stop period T2, at least one output switch 60 is changed from the connected state to the disconnected state, and at least another output switch is changed from the disconnected state to the connected state.

[0053] The order of output is not limited as long as the pulse voltage group 100 is output to all of the electrodes 38 to which the pulse voltage group 100 is to be output in the electrode assembly 24. For example, in the first operation example, when sequentially outputting to the plurality of electrodes 38i1 to 38i4 included in the same spline 36i, the pulse voltage group 100 may be output in an order different from the order from the first electrode 38i1 to the fourth electrode 38i4. Furthermore, in the first and second operation examples, the pulse voltage group 100 may be output to at least one electrode 38 included in each spline 36 in an order different from the order from the first spline 36a to the sixth spline 36f.

[0054] According to the present embodiment, a single first bridge circuit 50 can be used to output pulse voltage groups 100 to multiple electrodes 38 of the catheter 12. Therefore, the number of semiconductor switches included in the power supply device 14 can be reduced compared to when a first bridge circuit (for example, 24 first bridge circuits) is connected to each electrode 38. Since the semiconductor switches that make up the first bridge circuit 50 are more expensive than the mechanical relays that make up the output switch 60, reducing the number of semiconductor switches can reduce the cost of the power supply device 14.

[0055] (Second embodiment) 7 is a diagram schematically illustrating the circuit configuration of a power supply device 14A according to a second embodiment. The second embodiment differs from the first embodiment in that each of the output switches 60a-60f included in an output switching circuit 44A is connected to two or more electrodes 38 of each of the splines 36a-36f. The following description of the second embodiment will focus on the differences from the first embodiment, and will omit a description of the commonalities as appropriate.

[0056] The power supply device 14A includes a DC power supply 40, a pulse generating circuit 42, and an output switching circuit 44A. The DC power supply 40 and the pulse generating circuit 42 are configured similarly to those in the first embodiment. The output switching circuit 44A includes a plurality of output switches 60a-60f connected in parallel between the pulse generating circuit 42 and a plurality of electrodes 38a1-38f4 of the catheter 12. Each of the output switches 60a-60f is connected to two or more electrodes 38 out of the plurality of electrodes 38a1-38f4. The output switching circuit 44A may further include a measurement switch 70. The measurement switch 70 may be configured similarly to that in the first embodiment.

[0057] In the example shown in FIG. 7, each output switch 60i (i=a to f) is connected to a plurality of electrodes 38i1 to 38i4 included in each spline 36i. For example, the first output switch 60a is connected in parallel to the plurality of electrodes 38a1 to 38a4 included in the first spline 36a. The second output switch 60b is connected in parallel to the plurality of electrodes 38b1 to 38b4 included in the second spline 36b. A first contact 62 of each output switch 60a to 60f is connected to the pulse generating circuit 42. A second contact 64 of each output switch 60a to 60f is connected to the plurality of electrodes 38i1 to 38i4 included in each spline 36a to 36f. The output switching circuit 44A includes six output switches 60a to 60f corresponding to the six splines 36a to 36f.

[0058] FIG. 8 is a timing chart schematically illustrating an example of operation of the output switching circuit 44A. The output pattern of the pulse voltage groups 100a-100f in the example of operation shown in FIG. 8 is the same as that of the second example of operation shown in FIG. 6 described above. During the output period T1 of the first pulse voltage group 100a in the basic period T, the output switch 60a is in the connected state, and the other output switches 60b-60f are in the disconnected state. As a result, the pulse voltage group 100a is output to the multiple electrodes 38a1-38a4 of the first spline 36a. During the output period T1 of the next pulse voltage group 100b, the multiple (four) output switches 60b are in the connected state, and the other output switches 60a, 60c-60f are in the disconnected state. As a result, the pulse voltage group 100b is output to the multiple electrodes 38b1-38b4 of the second spline 36b. Similarly, pulse voltage groups 100 are sequentially output to the third spline 36c, the fourth spline 36d, the fifth spline 36e, and the sixth spline 36f. At this time, pulse voltage groups are simultaneously output to the multiple electrodes 38i1 to 38i4 within the same spline 36i. As a result, pulse voltage groups 100 are sequentially output to each of the splines 36a to 36f of the catheter 12, and one basic period T is completed. The basic period T shown in FIG. 8 can include six output periods T1.

[0059] According to this embodiment, it is possible to achieve an operation similar to the second operation example shown in Fig. 6 using a smaller number of output switches 60a to 60f than in the first embodiment. Although this embodiment cannot achieve an operation similar to the first operation example shown in Fig. 5, it is effective when only the second operation example is required. According to this embodiment, it is possible to achieve further cost reduction of the power supply device 14 by reducing the number of mechanical relays.

[0060] (Third embodiment) 9 is a diagram schematically illustrating the circuit configuration of a power supply device 14B according to a third embodiment. The third embodiment differs from the second embodiment in that an output switching circuit 44B includes a plurality of switches 80a1-80f4. The following description of the third embodiment will focus on the differences with the above-described embodiments, and will omit a description of the commonalities as appropriate.

[0061] The power supply device 14B includes a DC power supply 40, a pulse generating circuit 42, and an output switching circuit 44B. The DC power supply 40 and the pulse generating circuit 42 are configured similarly to those in the first and second embodiments. The output switching circuit 44B includes a plurality of output switches 60a-60f and a plurality of changeover switches 80a1-80f4 (collectively referred to as changeover switches 80).

[0062] Each of the output switches 60a-60f has a first contact 62 connected to the pulse generating circuit 42 and a second contact 64 connected to one of the plurality of changeover switches 80a1-80f4. Each of the output switches 60a-60f is provided corresponding to one of the splines 36a-36f of the catheter 12. The number of the plurality of output switches 60a-60f is the same as the number of the plurality of splines 36a-36f, which is, for example, six.

[0063] Each of the changeover switches 80a1-80f4 has a third contact 82 connected to each of the electrodes 38a1-38f4 of the catheter 12, a fourth contact 84 connected to the measurement device 18, and a fifth contact 86 connected to each of the output switches 60a-60f. Each of the changeover switches 80a1-80f4 is configured to connect the third contact 82 to either the fourth contact 84 or the fifth contact 86. Each of the changeover switches 80a1-80f4 is provided corresponding to each of the electrodes 38a1-38f4 of the catheter 12. The number of the changeover switches 80a1-80f4 is the same as the number of the electrodes 38a1-38f4, i.e., 24. Each of the changeover switches 80a1-80f4 can be configured by a mechanical relay, and may be the above-mentioned contact c relay.

[0064] 9, each output switch 60i (i=a to f) is connected in parallel to a plurality of changeover switches 80i1 to 80i4 connected to the plurality of electrodes 38i1 to 38i4 of each spline 36i. For example, the first output switch 60a is connected in parallel to the fifth contacts 86 of the plurality of changeover switches 80a1 to 80a4 connected to the plurality of electrodes 38a1 to 38a4 of the first spline 36a. The second output switch 60b is connected in parallel to the fifth contacts 86 of the plurality of changeover switches 80b1 to 80b4 connected to the plurality of electrodes 38b1 to 38b4 of the second spline 36b.

[0065] The control unit 46 controls the states of the plurality of output switches 60a-60f and the plurality of changeover switches 80a1-80f4. In the output mode, the control unit 46 connects the third contacts 82 of the plurality of changeover switches 80a1-80f4 to the fifth contact 86. In the output mode, the control unit 46 sequentially switches the states of the plurality of output switches 60a-60f to switch the splines 36a-36f to which the pulse voltage group 100 is output. In the output mode, the control unit 46 controls the states of the plurality of output switches 60a-60f in accordance with a time chart similar to that of FIG.

[0066] In the measurement mode, the control unit 46 puts the multiple output switches 60a to 60f into an OFF state and connects the third contact 82 of at least one changeover switch 80 among the multiple changeover switches 80a1 to 80f4 to the fourth contact 84. For example, in the measurement mode, the control unit 46 connects the third contact 82 of the changeover switch 80 connected to at least one electrode 38 used as a measurement terminal to the fourth contact 84, and connects the third contact 82 of the other changeover switches 80 to the fifth contact 86. In the measurement mode, the control unit 46 may connect the third contacts 82 of all of the multiple changeover switches 80a1 to 80f4 to the fourth contact 84.

[0067] According to this embodiment, by inserting changeover switches 80a1-80f4 between output switches 60a-60f and electrodes 38a1-38f4, it is possible to select an electrode 38 to be used as a measurement terminal. For example, measurement device 18 can be simultaneously and individually connected to multiple electrodes 38, improving the convenience of the measurement mode. For example, measurement device 18 can acquire potentials and currents from each of the multiple electrodes 38 to measure cardiac potentials and impedance.

[0068] (Fourth embodiment) 10 is a circuit diagram schematically illustrating the configuration of a power supply device 14C according to a fourth embodiment. The fourth embodiment differs from the first embodiment in that a pulse generating circuit 42C includes a plurality of first bridge circuits 50a-50f and an output switching circuit 44C includes a plurality of measurement switches 70a-70f. The following description of the fourth embodiment will focus on the differences from the first embodiment, and will omit a description of the commonalities as appropriate.

[0069] The power supply device 14C includes a DC power supply 40, a pulse generating circuit 42C, and an output switching circuit 44C. The DC power supply 40 has the same configuration as in the first embodiment. The pulse generating circuit 42C includes a plurality of first bridge circuits 50a-50f and a second bridge circuit 52. Each of the first bridge circuits 50a-50f has the same configuration as the bridge circuit 50 according to the first embodiment. Each of the first bridge circuits 50a-50f is provided corresponding to each of the splines 36a-36f of the catheter 12. The number of the plurality of first bridge circuits 50a-50f is the same as the number of the plurality of splines 36a-36f, for example, six.

[0070] The output switching circuit 44C includes a plurality of output switches 60a1-60f4. Each of the output switches 60a1-60f4 includes a first contact 62 connected to the pulse generating circuit 42 and a second contact 64 connected to each of the electrodes 38a1-38f4. The first contacts 62 of the plurality of output switches 60i1-60i4 connected to the plurality of electrodes 38i1-38i4 of each spline 36i (i = a-f) are connected to the output 58i of the corresponding first bridge circuit 50i. For example, the first contacts 62 of the plurality of output switches 60a1-60a4 connected to the plurality of electrodes 38a1-38a4 of the first spline 36a are connected to the output 58a of the corresponding first bridge circuit 50a. Similarly, the first contacts 62 of the plurality of output switches 60b1-60b4 connected to the plurality of electrodes 38b1-38b4 of the second spline 36b are connected to the output 58b of the corresponding first bridge circuit 50b.

[0071] The output switching circuit 44C may further include a plurality of measurement switches 70a-70f (collectively referred to as measurement switches 70). Each of the measurement switches 70a-70f has a third contact 72 connected to the first contacts 62 of the plurality of output switches 60a1-60f4 and a fourth contact 74 connected to the measurement device 18. The measurement switches 70 may be configured by a mechanical relay. Each of the measurement switches 70a-70f is provided corresponding to each of the splines 36a-36f of the catheter 12. The third contact 72 of each measurement switch 70i (i = a-f) is connected to the first contacts 62 of the plurality of output switches 60i1-60i4 connected to the plurality of electrodes 38i1-38i4 of each spline 36i. The third contact 72 of each measurement switch 70i (i = a-f) is connected to the output 58i of the corresponding first bridge circuit 50i.

[0072] The control unit 46 selectively operates one of the plurality of first bridge circuits 50a-50f to cause the pulse generation circuit 42C to output the pulse voltage group 100. For example, the control unit 46 can operate the pulse generation circuit 42C and the output switching circuit 44C in the same manner as the first operation example shown in FIG. 5. In the fourth embodiment, the pulse voltage groups 100a1-100f4 shown in FIG. 5 are generated by selectively operating one of the plurality of first bridge circuits 50a-50f. For example, the pulse voltage groups 100a1-100a4 output to the plurality of electrodes 38a1-38a4 of the first spline 36a are generated using the first bridge circuit 50a.

[0073] The control unit 46 may operate the pulse generating circuit 42C and the output switching circuit 44C in the same manner as in the second operation example shown in Fig. 6. In the fourth embodiment, the pulse voltage groups 100a-100f shown in Fig. 6 are generated by selectively operating one of the plurality of first bridge circuits 50a-50f. For example, the pulse voltage group 100a output to the plurality of electrodes 38a1-38a4 of the first spline 36a is generated using the first bridge circuit 50a.

[0074] The pulse generating circuit 42C according to the fourth embodiment may operate to output a voltage waveform different from the output voltage waveform shown in FIG. 4(b). FIG. 11 is a diagram schematically illustrating an example of an output voltage waveform of the pulse generating circuit 42C. In the third operation example shown in FIG. 11, the first bridge circuits 50a to 50f that output the pulse voltage are sequentially switched each time a pulse voltage (e.g., a biphasic pulse) is output. First, the first bridge circuit 50a and the second bridge circuit 52 are operated in the first unit period T3a to output a first positive voltage phase pulse 102a and a first negative voltage phase pulse 104a. Next, the first bridge circuit 50b and the second bridge circuit 52 are operated in the second unit period T3b to output a second positive voltage phase pulse 102b and a second negative voltage phase pulse 104b. Similarly, a biphasic pulse is output using each of the first bridge circuits 50a to 50f and the second bridge circuit 52. Finally, in a sixth unit period T3f, the first bridge circuit 50f and the second bridge circuit 52 are operated to output a sixth positive voltage phase pulse 102f and a sixth negative voltage phase pulse 104f, completing one cycle period T4. The operation of each unit period T3a-T3f is the same as the unit period T3 shown in FIG. 4(b). In the third operation example shown in FIG. 11, the cycle period T4 is repeated multiple times to generate the pulse voltage group 100 shown in FIG. 4(a). The number of repetitions of the cycle period T4 included in the pulse voltage group 100 is not particularly limited, but is, for example, between 2 and 100 times.

[0075] 11, the control unit 46 may connect all of the output switches 60a1 to 60f4. In this case, the first bridge circuits 50a to 50f that output the pulse voltage are sequentially switched, and the splines 36a to 36f to which the pulse voltage is applied are sequentially switched. The switching cycle of the pulse voltage in this case corresponds to the time length of the unit periods T3a to T3f.

[0076] According to this embodiment, in addition to the first operation example shown in Fig. 5 and the second operation example shown in Fig. 6, a third operation example using the voltage waveform shown in Fig. 11 can be used. According to this embodiment, it is possible to increase the variation in the operation of power supply device 14. Also, in this embodiment, the number of semiconductor switches included in power supply device 14 can be reduced compared to when a first bridge circuit (for example, 24 first bridge circuits) is provided for each electrode 38, and the cost of power supply device 14 can be reduced.

[0077] (Fifth embodiment) 12 is a circuit diagram schematically illustrating the configuration of a power supply device 14D according to a fifth embodiment. In the fifth embodiment, a pulse generating circuit 42D includes a plurality of first bridge circuits 50a-50f, similar to the fourth embodiment. In the fifth embodiment, an output switching circuit 44D includes a plurality of changeover switches 90a1-90f4. The following description of the fifth embodiment will focus on the differences from the above-described embodiments, and will omit a description of the commonalities as appropriate.

[0078] The power supply device 14D includes a DC power supply 40, a pulse generating circuit 42D, and an output switching circuit 44D. The DC power supply 40 is configured similarly to that of the first embodiment. The pulse generating circuit 42D is configured similarly to the pulse generating circuit 42C according to the fourth embodiment. The output switching circuit 44D includes a plurality of changeover switches 90a1 to 90f4 (collectively referred to as changeover switches 90).

[0079] Each of the changeover switches 90a1-90f4 has a first contact 92 connected to each of the electrodes 38a1-38f4 of the catheter 12, a second contact 94 connected to the measurement device 18, and a third contact 96 connected to the pulse generating circuit 42D. Each of the changeover switches 90a1-90f4 is configured to connect the first contact 92 to either the second contact 94 or the third contact 96. Each of the changeover switches 80a1-80f4 is provided corresponding to each of the electrodes 38a1-38f4 of the catheter 12. The number of the changeover switches 80a1-80f4 is the same as the number of the electrodes 38a1-38f4, which is, for example, 24.

[0080] The third contacts 96 of the multiple changeover switches 90i1-90i4 connected to the multiple electrodes 38i1-38i4 of each spline 36i (i=a-f) are connected to the output 58i of the corresponding first bridge circuit 50i. For example, the third contacts 96 of the multiple changeover switches 90a1-90a4 connected to the multiple electrodes 38a1-38a4 of the first spline 36a are connected to the output 58a of the corresponding first bridge circuit 50a. Similarly, the third contacts 96 of the multiple changeover switches 90b1-90b4 connected to the multiple electrodes 38b1-38b4 of the second spline 36b are connected to the output 58b of the corresponding first bridge circuit 50b.

[0081] The control unit 46 can operate the pulse generating circuit 42D in the same manner as in the third operation example shown in Fig. 11. In this case, in the output mode, the control unit 46 connects the first contacts 92 of the multiple selector switches 90a1-90a4 to the third contact 96. In the measurement mode, the control unit 46 stops the generation of pulse voltages by the pulse generating circuit 42D and connects the first contacts 92 of the multiple selector switches 90a1-90a4 to the second contact 94.

[0082] According to this embodiment, it is possible to use the third operation example shown in Fig. 11. In this embodiment as well, the number of semiconductor switches included in power supply device 14 can be reduced compared to when a first bridge circuit (for example, 24 first bridge circuits) is provided for each electrode 38, and the cost of power supply device 14 can be reduced.

[0083] In the above-described embodiment, the case where the pulse voltage group 100 is applied to the first electrode 38i1 to the fourth electrode 38i4 provided on each spline 36i has been described. However, in another embodiment, the pulse voltage group 100 may be applied to only some of the first electrode 38i1 to the fourth electrode 38i4 (for example, the first electrode 38i1 to the third electrode 38i3). In this case, the output switch 60 does not need to be connected to some of the electrodes to which the pulse voltage group 100 is not applied (for example, the fourth electrode 38i4). The some of the electrodes to which the pulse voltage group 100 is not applied (for example, the fourth electrode 38i4) may be used for potential measurement or may be used as an indifferent electrode.

[0084] In the above-described embodiment, by limiting the number of electrodes 38 to which the pulse voltage is simultaneously applied, the region that can be formed by the electrode assembly 24 can be made larger than when the pulse voltage is simultaneously applied to all electrodes 38a1-38f4 of the catheter 12. This is because, when a voltage is applied simultaneously to all electrodes 38a1-38f4 of the electrode assembly 24, the current flows in a dispersed manner, resulting in a decrease in current density. On the other hand, when the pulse voltage is applied only to each electrode 38 or to multiple electrodes 38i1-38i4 of each spline 36i, the pulse voltage can be concentrated on a limited number of electrodes 38, thereby increasing the current density. Furthermore, when the pulse voltage group 100 is continuously applied, providing a pause period T2 can suppress the occurrence of patient movement due to PFA.

[0085] Although the above embodiment has been described with respect to the application of biphasic pulses, another embodiment may apply monophasic pulses, in which case the first bridge circuit 50 can be replaced by a single semiconductor switch, and the second bridge circuit 52 can be omitted.

[0086] In the above embodiment, the case where the pulse voltage is applied to the plurality of electrodes 38a1 to 38f4 provided on the plurality of splines 36a to 36f of the electrode assembly 24 has been described, but in another embodiment, the pulse voltage may be applied to an electrode catheter having a configuration different from that of the electrode assembly 24. For example, the shaft 26 may not be provided with the plurality of splines 36 at its tip, and the pulse voltage may be applied to the plurality of electrodes 38 arranged on the shaft 26.

[0087] The present disclosure has been described above based on the embodiments. Various modifications are possible to the combinations of the components and processes in the exemplary embodiments, and it will be obvious to those skilled in the art that such modifications are included within the scope of the present disclosure.

[0088] Some aspects of the present disclosure are as follows.

[0089] A first aspect is a power supply device that supplies pulse voltages to multiple electrodes of a catheter, and includes a pulse generation circuit that generates pulse voltages by switching a DC voltage, and an output switching circuit that is connected between the pulse generation circuit and the multiple electrodes and switches the electrodes to which the pulse voltage is output. According to the first aspect, by using an output switching circuit that switches the output destination of the pulse voltage, it is possible to reduce the cost of the power supply device compared to using multiple pulse generation circuits that output pulse voltages to each electrode.

[0090] A second aspect is the power supply device according to the first aspect, wherein the pulse generating circuit includes a semiconductor switch and the output switching circuit includes a mechanical switch. According to the second aspect, the number of expensive semiconductor switches used can be reduced, thereby realizing a cost reduction of the power supply device.

[0091] In a third aspect, in the power supply device according to the first or second aspect, the output switching circuit includes a plurality of switches connected in parallel between the pulse generating circuit and the plurality of electrodes. According to the third aspect, by switching the connection states of the plurality of switches, it is possible to switch the electrodes to which the pulse voltage is output.

[0092] A fourth aspect is the power supply device according to any one of the first to third aspects, wherein the pulse generating circuit includes a first bridge circuit connected to the output switching circuit and a second bridge circuit connected to a counter electrode, and the output switching circuit includes a plurality of switches, each connected between the first bridge circuit and at least one of the plurality of electrodes. According to the fourth aspect, the electrode to which the pulse voltage is output can be switched by switching the connection state of the switches connected between the first bridge circuit and the electrode.

[0093] A fifth aspect is the power supply device according to any one of the first to third aspects, wherein the pulse generation circuit includes a plurality of first bridge circuits connected to the output switching circuit and a second bridge circuit connected to a return electrode, and the output switching circuit includes a plurality of switches, each connected between each bridge circuit of the plurality of first bridge circuits and at least one of the plurality of electrodes. According to the fifth aspect, by using a plurality of first bridge circuits, it is possible to increase the variety of pulse voltage output patterns. The second bridge circuit connected to the return electrode can be shared, thereby reducing the cost of the power supply device.

[0094] A sixth aspect is the power supply device according to any one of the first to fifth aspects, wherein the catheter includes a shaft, a plurality of splines arranged around the axial direction of the shaft, and a plurality of electrodes provided on the plurality of splines, and the output switching circuit includes a plurality of switches, each connected to at least one electrode provided on each of the plurality of splines. According to the sixth aspect, the output destination of the pulse voltage can be switched on a spline-by-spline basis.

[0095] A seventh aspect is the power supply device according to the sixth aspect, wherein each of the plurality of switches is connected to two or more electrodes provided on each of the plurality of splines. According to the seventh aspect, the electrodes to which the pulse voltage is output can be switched on a spline-by-spline basis.

[0096] An eighth aspect is the power supply device according to the sixth aspect, wherein each switch of the plurality of switches is connected to a corresponding one of the plurality of electrodes. According to a seventh aspect, the output destination of the pulse voltage can be switched on an electrode-by-electrode basis.

[0097] A ninth aspect is the power supply device according to any one of the first to eighth aspects, further comprising a control unit that operates the pulse generation circuit to include an output period during which the pulse voltage is repeatedly output and a stop period that is longer than the output period during which output of the pulse voltage is stopped, maintains the state of the output switching circuit during the output period, and changes the state of the output switching circuit during the stop period. By providing a relatively long stop period, it is possible to switch the output destination of the pulse voltage using a switch with a relatively long switching time, thereby realizing a low cost power supply device.

[0098] In a tenth aspect, in the power supply device according to the ninth aspect, the control unit operates the pulse generating circuit so that the output periods and the stop periods are alternately repeated, and changes the state of the output switching circuit during the stop period so that the electrodes to which the pulse voltage is output differ in two output periods sandwiching the stop period. According to the tenth aspect, the output destination of the pulse voltage can be switched sequentially for each output period.

[0099] An eleventh aspect is the power supply device according to any one of the first to tenth aspects, wherein the output switching circuit includes an output switch having a first contact connected to the pulse generating circuit and a second contact connected to at least one of the plurality of electrodes, and a measurement switch having a third contact connected to the pulse generating circuit and a fourth contact connected to a measuring device. According to the eleventh aspect, the provision of the output switch makes it possible to switch the output destination of the pulse voltage. The provision of the measurement switch makes it possible to protect the measuring device when the pulse voltage is output.

[0100] A twelfth aspect is the power supply device according to any one of claims 1 to 10, wherein the output switching circuit has a first contact connected to at least one of the plurality of electrodes, a second contact connected to a measuring device, and a third contact connected to the pulse generating circuit, and further comprises a changeover switch that connects the first contact to the second contact or the third contact. According to the twelfth aspect, by providing the changeover switch, it is possible to protect the measuring device when a pulse voltage is output.

[0101] A thirteenth aspect is the power supply device according to any one of the first to tenth aspects, wherein the output switching circuit includes an output switch and a changeover switch, the output switch having a first contact connected to the pulse generating circuit and a second contact, the changeover switch having a third contact connected to at least one of the plurality of electrodes, a fourth contact connected to a measuring device, and a fifth contact connected to the second contact, and the third contact is connected to the fourth contact or the fifth contact. According to the thirteenth aspect, the provision of the output switch makes it possible to change the output destination of the pulse voltage. The provision of the changeover switch makes it possible to protect the measuring device when the pulse voltage is output.

[0102] A fourteenth aspect is the power supply device according to any one of the eleventh to thirteenth aspects, further comprising a control circuit that operates the pulse generating circuit to include an output period during which the pulse voltage is repeatedly output and a stop period longer than the output period during which output of the pulse voltage is stopped, maintains the state of the output switching circuit during the output period, and changes the state of the output switching circuit during the stop period, and the measurement device uses at least one electrode of the plurality of electrodes connected via the output switching circuit as a measurement terminal during the stop period. According to the fourteenth aspect, at least one electrode can be connected to the measurement device when the pulse voltage is stopped, and the at least one electrode can be used as a measurement terminal.

[0103] A fifteenth aspect is an ablation system comprising: a catheter having a plurality of electrodes; a return electrode; and a power supply device that supplies a pulse voltage between at least one of the plurality of electrodes and the return electrode, the power supply device comprising: a pulse generation circuit that generates the pulse voltage by switching a DC voltage; and an output switching circuit that is connected between the pulse generation circuit and the plurality of electrodes and switches the electrode to which the pulse voltage is output. According to the fifteenth aspect, by using the output switching circuit that switches the output destination of the pulse voltage, it is possible to reduce the cost of the power supply device compared to using a plurality of pulse generation circuits for outputting pulse voltages to each electrode. [Explanation of symbols]

[0104] 10...Ablation system, 12...Catheter, 14...Power supply unit, 16...Return electrode, 18...Measuring device, 24...Electrode assembly, 26...Shaft, 36...Spline, 38...Electrode, 42...Pulse generating circuit, 44...Output switching circuit, 46...Control unit, 50...First bridge circuit, 52...Second bridge circuit, 60...Output switch, 70...Measuring switch, 80, 90...Switching switch.

Claims

1. A power supply device for supplying pulse voltages to a plurality of electrodes of a catheter, a pulse generating circuit that switches a DC voltage to generate a pulse voltage; an output switching circuit connected between the pulse generating circuit and the plurality of electrodes, for switching the electrodes to which the pulse voltage is output; power supply.

2. the pulse generating circuit includes a semiconductor switch; The output switching circuit includes a mechanical switch. The power supply device of claim 1 .

3. the output switching circuit includes a plurality of switches connected in parallel between the pulse generating circuit and the plurality of electrodes; The power supply device of claim 1 .

4. the pulse generating circuit includes a first bridge circuit connected to the output switching circuit and a second bridge circuit connected to a return electrode; the output switching circuit includes a plurality of switches, each of which is connected between the first bridge circuit and at least one of the plurality of electrodes; The power supply device of claim 1 .

5. the pulse generating circuit includes a plurality of first bridge circuits connected to the output switching circuit and a second bridge circuit connected to a return electrode; the output switching circuit includes a plurality of switches, each of which is connected between a respective bridge circuit of the plurality of first bridge circuits and at least one of the plurality of electrodes; The power supply device of claim 1 .

6. The catheter includes a shaft, a plurality of splines arranged around the axial direction of the shaft, and the plurality of electrodes provided on the plurality of splines, the output switching circuit includes a plurality of switches, each connected to at least one electrode provided on each of the plurality of splines; 6. The power supply device according to claim 1.

7. Each switch of the plurality of switches is connected to two or more electrodes provided on each spline of the plurality of splines.

7. The power supply device according to claim 6.

8. Each switch of the plurality of switches is connected to a corresponding electrode of the plurality of electrodes.

7. The power supply device according to claim 6.

9. a control unit that operates the pulse generation circuit so as to include an output period during which the pulse voltage is repeatedly output and a stop period that is longer than the output period during which output of the pulse voltage is stopped, maintains a state of the output switching circuit during the output period, and changes the state of the output switching circuit during the stop period; 6. The power supply device according to claim 1.

10. the control unit operates the pulse generation circuit so that the output period and the stop period are alternately repeated, and changes the state of the output switching circuit during the stop period so that the electrodes to which the pulse voltage is output differ during two output periods sandwiching the stop period.

10. The power supply device of claim 9.

11. the output switching circuit includes an output switch having a first contact connected to the pulse generating circuit and a second contact connected to at least one of the plurality of electrodes, and a measurement switch having a third contact connected to the pulse generating circuit and a fourth contact connected to a measurement device. The power supply device of claim 1 .

12. the output switching circuit has a first contact connected to at least one of the plurality of electrodes, a second contact connected to a measurement device, and a third contact connected to the pulse generating circuit, and includes a changeover switch that connects the first contact to the second contact or the third contact. The power supply device of claim 1 .

13. the output switching circuit includes an output switch and a changeover switch; the output switch has a first contact connected to the pulse generating circuit and a second contact; the changeover switch has a third contact connected to at least one of the plurality of electrodes, a fourth contact connected to a measuring device, and a fifth contact connected to the second contact, and connects the third contact to the fourth contact or the fifth contact; The power supply device of claim 1 .

14. a control circuit that operates the pulse generation circuit so as to include an output period during which the pulse voltage is repeatedly output and a stop period that is longer than the output period during which output of the pulse voltage is stopped, maintains a state of the output switching circuit during the output period, and changes the state of the output switching circuit during the stop period, the measurement device uses at least one electrode of the plurality of electrodes connected via the output switching circuit as a measurement terminal during the stop period; 14. The power supply device according to any one of claims 11 to 13.

15. a catheter having a plurality of electrodes; A return electrode; a power supply device that supplies a pulse voltage between at least one of the plurality of electrodes and the return electrode, The power supply device a pulse generating circuit that switches a DC voltage to generate a pulse voltage; an output switching circuit connected between the pulse generating circuit and the plurality of electrodes, for switching the electrodes to which the pulse voltage is output; Ablation system.

Images