JP2012135457A - Heart stimulation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heart stimulation device for improving a defibrillation effect and also starting the treatment of a heart in an early stage.SOLUTION: The heart stimulation device 1 is adopted, which includes: a capacitor 21 for storing power to generate a first waveform pulse; a capacitor 22 for storing power to generate a second waveform pulse with a voltage higher than that of the first waveform pulse; SWs 31-36 arranged in a circuit between the capacitors 21, 22 and output terminals 41, 42; and a control part 30 for controlling the SWs 31-36, and where the control part 30 controls the SWs 31-36 to output the first waveform pulse multiple times at time interval before the output of the second waveform pulse and also to superimpose the discharge period of the capacitor 21 on the charge period of the capacitor 22.

Description

  The present invention relates to a cardiac stimulating device.

  2. Description of the Related Art Conventionally, a heart stimulating device (system) for cardiac defibrillation or cardioversion is known (see, for example, Patent Document 1). This cardiac stimulating device includes a plurality of main electrodes, a power source, and a control circuit, and generates a plurality of types of pulses (auxiliary pulse and main pulse) for defibrillation.

Special table 2001-514567 gazette

  Patent Document 1 describes that the defibrillation effect is enhanced by outputting the main pulse after outputting the auxiliary pulse. However, in the heart stimulating device disclosed in Patent Document 1, since a pulse having a magnitude substantially equal to that of the main pulse is output as the auxiliary pulse, it takes a charging time for the auxiliary pulse, and after sufficient charging, Otherwise, the auxiliary pulse cannot be output. In other words, the heart stimulating device disclosed in Patent Document 1 has a disadvantage that it is not possible to start heart treatment at an early stage.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a cardiac stimulation device that can improve the defibrillation effect and can start the treatment of the heart at an early stage.

In order to achieve the above object, the present invention employs the following means.
The present invention includes a pulse generating means for generating a pulse for stimulating the heart, a first capacitor for storing electric power for generating a first pulse by the pulse generating means, and the first pulse by the pulse generating means. A second capacitor for storing electric power for generating a second pulse having a higher voltage than the first capacitor, at least one voltage applying means for applying a voltage to each of the first capacitor and the second capacitor, Control means for controlling the pulse generation means, wherein the control means outputs the first pulse a plurality of times at time intervals prior to the output of the second pulse, and the first capacitor A cardiac stimulating device that controls the pulse generating means is employed so that the discharge period and the charging period of the second capacitor overlap.

  According to the present invention, the heart can be stimulated by the pulse generated by the pulse generating means to remove the fibrillation of the heart. In this case, prior to the output of the second pulse, the control means outputs the first pulse having a voltage lower than that of the second pulse a plurality of times with a time interval, and the discharge period of the first capacitor. The pulse generation means is controlled so that the (period in which the first pulse is output) and the charging period of the second capacitor (period in which the electric power for generating the second pulse is charged) overlap.

  By outputting the first pulse a plurality of times in this manner, the defibrillation effect can be obtained even if the voltage of the first pulse is lowered, and the first capacitor is charged to output the first pulse. The period can be shortened. Accordingly, the first pulse can be output during the charging period of the second capacitor for outputting the second pulse, and the heart treatment can be started at an early stage. Further, by outputting the first pulse prior to the output of the second pulse, the voltage required for defibrillation (the voltage of the second pulse) can be reduced, and the heart fibrillation can be effectively performed. Can be removed.

In the above invention, the control means may control the pulse generation means so as to output the first pulse at a time interval shorter than the refractory period of the heart.
The refractory period of the heart refers to a period immediately after ventricular excitement and the heart does not respond to any stimulus. Therefore, by outputting the first pulse at a time interval shorter than the refractory period of the heart, it is possible to obtain the same effect as when the voltage is constantly applied to the heart, and the first pulse Power consumption accompanying output can be reduced.

In the above invention, the voltage applying means for applying a voltage to the first capacitor and the second capacitor may be shared.
By doing in this way, it is possible to generate the first pulse and the second pulse by applying a voltage to the first capacitor and the second capacitor by one common voltage applying means, The size of the apparatus can be reduced.

In the above invention, a plurality of the first capacitors may be provided, and the control means may control the pulse generating means so that the discharge periods of the plurality of first capacitors are different.
By doing so, the charging time can be set longer for each of the plurality of capacitors, so that a necessary pulse voltage can be generated reliably.

In the above invention, the control means may control the voltage application means so as to charge in at least a part of a stop period between the plurality of first pulses to be output.
In this way, efficient charging can be performed during the pulse stop period.

In the above invention, a first output terminal that outputs the first pulse and a second output terminal that outputs the second pulse may be provided.
By doing so, it is possible to output the high voltage second pulse from the second output terminal and output the low voltage first pulse from the first output terminal. By separating the output terminals of the first pulse and the second pulse in this way, the electrodes connected to the output terminals can be arranged at different positions in the living body, and different positions can be stimulated by each pulse. . As a result, stimulation by the first pulse and the second pulse can be performed on an appropriate position in the living body, and defibrillation can be performed effectively.

  ADVANTAGE OF THE INVENTION According to this invention, while improving a defibrillation effect, there exists an effect that the treatment of a heart can be started at an early stage.

1 is an overall configuration diagram of a cardiac stimulation device according to an embodiment of the present invention. It is a timing chart which shows the relationship between the charge timing to each capacitor | condenser of the cardiac stimulation apparatus of FIG. 1, and a pulse output timing. It is a timing chart which shows the operation | movement of the switch of the heart stimulating device of FIG. It is a flowchart which shows the process performed by the control part of the cardiac stimulation apparatus of FIG. It is a figure explaining the output timing of a 1st waveform pulse in the cardiac stimulation apparatus of FIG. It is a whole block diagram of the heart stimulating device which concerns on a 1st modification. It is a whole block diagram of the heart stimulating device which concerns on a 2nd modification. It is a whole block diagram of the heart stimulating device which concerns on a 3rd modification. It is a timing chart which shows the relationship between the charge timing to each capacitor | condenser of the cardiac stimulation apparatus of FIG. 8, and a pulse output timing.

A cardiac stimulation apparatus 1 according to an embodiment of the present invention will be described below with reference to the drawings.
As shown in FIG. 1, the heart stimulating apparatus 1 according to the present embodiment applies a power supply 10 that applies a voltage, transformers 11 and 12 that convert a voltage applied by the power supply 10, and a voltage from the transformer 11. The capacitor (first capacitor) 21 to be charged by being applied, the capacitor (second capacitor) 22 to be charged by being applied with the voltage from the transformer 12, and the output connected to the outside (electrode) Terminals 41 and 42, switches (pulse generating means) 31 to 36 provided in a circuit between the capacitors 21 and 22 and the output terminals 41 and 42, and a control unit (control means) 30 for controlling them. ing.

  A lead wire (not shown) is connected to the output terminals 41 and 42, and the other end of the lead wire is connected to an electrode (not shown) disposed in the heart. Thereby, the pulse generated from the heart stimulating device 1 is transmitted to the electrode arranged in the heart, and the heart is stimulated by the pulse to remove the fibrillation of the heart.

  The capacitor 21 is connected to the transformer 11 and is charged with electric power for generating a low-voltage first waveform pulse (first pulse) by the voltage applied by the transformer 11. Further, the capacitor 21 discharges electric power charged in the capacitor 21 by performing ON / OFF operations of switches (hereinafter referred to as “SW”) 31 to 36 as will be described later. A low voltage first waveform pulse is output.

The capacitor 22 is connected to the transformer 12 and is charged with electric power for generating a high-voltage second waveform pulse (second pulse) by the voltage applied by the transformer 12. Further, the capacitor 22 performs the ON / OFF operation of the SWs 31 to 36 as described later, thereby discharging the power charged in the capacitor 22 and outputting a high-voltage second waveform pulse from the output terminals 41 and 42. It is like that.
Here, the capacity of the capacitor 21 may be set larger than the capacity of the capacitor 22 to reduce a voltage drop caused by a plurality of pulse outputs.

  SW31 to 36 are switches provided in a circuit between the capacitors 21 and 22 and the output terminals 41 and 42, and the ON / OFF operation of each circuit is switched by performing an ON / OFF operation, so that the output terminal 41 , 42 outputs a pulse for stimulating the heart.

SW31 and 32 are connected to the capacitor 22 and to SW35 and 36, respectively.
SW33 and 34 are connected to the capacitor 21 and to SW35 and 36, respectively.
The SWs 35 and 36 are grounded.

A wiring 43 is connected between SW31 and SW35 and between SW33 and SW35, and the other end of the wiring 43 is connected to the output terminal 41.
A wiring 44 is connected between SW 32 and SW 36 and between SW 34 and SW 36, and the other end of the wiring 44 is connected to the output terminal 42.

  The control unit 30 controls ON / OFF operations of the SWs 31 to 36 and controls charging of the capacitors 21 and 22 by the transformers 11 and 12. Specifically, as shown in FIG. 2, the controller 30 outputs the first waveform pulse from the capacitor 21 a plurality of times at time intervals prior to the output of the second waveform pulse from the capacitor 22. It is like that. In addition, the control unit 30 controls the SWs 31 to 36 and the transformers 11 and 12 so that the charging period of the capacitor 21 and the discharging period of the capacitor 22 overlap.

  That is, as shown in FIG. 2, the control unit 30 outputs the first waveform pulse from the capacitor 21 to the output terminals 41 and 42 during the charging period of the capacitor 22, and starts defibrillation therapy. ing. Here, the voltage (charge voltage) applied to the capacitor 21 is, for example, 10 to 90V, and the voltage (charge voltage) applied to the capacitor 22 is, for example, 70 to 500V. These charging voltages become the amplitude of the pulse output. The capacitor 21 is charged while the output of the first waveform pulse is stopped, and the discharged charge is charged. In FIG. 2, charging is performed during the entire period in which the output of the first waveform pulse is stopped. However, it is sufficient that the target applied voltage can be charged to the capacitor 21. Charging during only a part of the period may be used.

Here, specific control of the SWs 31 to 36 when generating a defibrillation pulse will be described with reference to FIG.
FIG. 3 is a timing chart showing a specific ON / OFF operation of SW31 to SW36.
As shown in FIG. 3, the first waveform pulse from the capacitor 21 is generated by controlling the SWs 33 to 36. Specifically, SW33 and SW36 are turned on to generate a positive pulse, and SW34 and SW35 are turned on to generate a negative pulse.
Further, the second waveform pulse from the capacitor 22 is generated by controlling SW31 to 32 and SW35 to 36. Specifically, SW31 and SW36 are turned on to generate a positive pulse, and SW32 and SW35 are turned on to generate a negative pulse.

The operation of the heart stimulating apparatus 1 according to this embodiment that performs the above control will be described with reference to the flowchart shown in FIG.
First, when fibrillation is detected and the process proceeds to a defibrillation pulse generation process, charging of the capacitor 21 and the capacitor 22 is started (step S1).
Next, it is confirmed whether or not the capacitor 21 has reached the set voltage (step S2).

If the preset voltage has been reached in step S2, the voltage of the capacitor 22 is confirmed (step S4).
On the other hand, if the capacitor 21 does not reach the set voltage within a predetermined time in step S2 (step S3), it is determined that some abnormality has occurred and an error warning is issued (step S12). The generation process ends.

In step S4, if the capacitor 22 has reached a preset voltage, a first waveform pulse is output (step S6).
On the other hand, if the capacitor 22 does not reach the set voltage within a predetermined time in step S4 (step S5), it is determined that some abnormality has occurred and an error warning is issued (step S12), and the defibrillation pulse The generation process ends.

Next, after outputting the first waveform pulse, it is confirmed that the output timing of the second waveform pulse is reached (step S7).
If the output timing of the second waveform pulse is reached in step S7, charging of the capacitor 22 is terminated (step S8), the output of the first waveform pulse is stopped (step S9), and the second waveform pulse is output. Output is started (step S10).
Then, the output of the second waveform pulse is stopped (step S11), and the defibrillation pulse generation process is terminated.

  As described above, according to the heart stimulating device 1 according to the present embodiment, the control unit 30 sets the time interval of the first waveform pulse having a voltage lower than that of the second waveform pulse before the output of the second waveform pulse. The capacitor is output a plurality of times, and the discharging period of the capacitor 21 (the period for outputting the first waveform pulse) and the charging period of the capacitor 22 (the period for charging the electric power for generating the second waveform pulse) are overlapped. SW31 to 36 are controlled.

  By outputting the first waveform pulse a plurality of times in this way, the defibrillation effect can be obtained even if the voltage of the first waveform pulse is lowered, and the charging period of the capacitor 21 for outputting the first waveform pulse is increased. Can be shortened. Thus, the first waveform pulse can be output during the charging period of the capacitor 22 for outputting the second waveform pulse, and the heart treatment can be started at an early stage. Also, by outputting the first waveform pulse prior to the output of the second waveform pulse, the voltage required for defibrillation (the voltage of the second waveform pulse) can be reduced, and defibrillation can be effectively performed. It can be carried out.

  In the heart stimulating apparatus 1 according to the present embodiment, as shown in FIG. 5, the first waveform pulse having a low voltage may be continuously output at an interval shorter than the refractory period of the heart. Here, the refractory period of the heart refers to a period immediately after the ventricular excitement and the heart does not respond to any stimulation. Therefore, by outputting the first pulse continuously with an interval shorter than the refractory period of the heart, it is possible to obtain the same effect as when a voltage is constantly applied to the heart.

  Specifically, as shown in FIG. 5, for example, the first waveform pulse is output at about 10 V to 90 V for a period of 1 ms (H level), and the pulse is output for a period set shorter than the refractory period of the heart. Is stopped (L level). As a result, it is possible to obtain the same effect as when a voltage is constantly applied to the heart, and to reduce the power consumption associated with the output of the first pulse by the amount during the stop period. Note that the output period of the first waveform pulse is not limited to 1 ms, and may be set longer than the period in which the heart responds.

[First modification]
As a first modification of the heart stimulating apparatus 1 according to the present embodiment, a transformer that applies a voltage to the capacitors 21 and 22 may be shared as shown in FIG.
As shown in FIG. 6, the heart stimulating device 2 according to the present modification includes a primary of a capacitor 21 for generating a low-voltage first waveform pulse and a capacitor 22 for generating a high-voltage second waveform pulse. A transformer 13 is connected to the side. A voltage is applied to each of the capacitors 21 and 22 by the transformer 13.

In addition, the control unit 30 performs charge control on the capacitor 21 and charge control on the capacitor 22 with respect to the transformer 13.
According to the heart stimulating device 2 according to the present modification, in addition to the same effects as those of the heart stimulating device 1 described above, the transformers of the capacitors 21 and 22 can be shared, so that the size of the device can be reduced. it can.

[Second modification]
As a second modification of the heart stimulating device 1 according to the present embodiment, as shown in FIG. 7, two pairs of output terminals connected to the outside (electrodes) may be provided.
As shown in FIG. 7, the heart stimulating device 3 according to the present modification has the same configuration (see FIG. 1) as the above-described heart stimulating device 1, and output terminals 45 and 46 connected to the outside (electrodes). And SWs 37 and 38 provided in a circuit between the capacitors 21 and 22 and the output terminals 45 and 46.

  In the heart stimulating device 3 according to this modification, a lead wire (not shown) is connected to the output terminals 45 and 46 in the same manner as the output terminals 41 and 42, and the other end of the lead wire is an electrode disposed on the heart. (Not shown). Thereby, the pulse generated from the heart stimulating device 3 is transmitted to the electrode arranged in the heart, and the heart is stimulated by the pulse to remove the fibrillation of the heart.

  SW31 to 38 are switches provided in a circuit between the capacitors 21 and 22 and the output terminals 41 and 42 and the output terminals 45 and 46, and ON / OFF of each circuit is performed by performing an ON / OFF operation. By switching, pulses for stimulating the heart are output from the output terminals 41 and 42 and the output terminals 45 and 46.

SW31 and 32 are connected to the capacitor 22 and to SW35 and 36, respectively.
SW33 and 34 are connected to the capacitor 21 and to SW37 and 38, respectively.
The SWs 35, 36, 37, and 38 are grounded.

A wiring 43 is connected between SW 31 and SW 35, and the other end of the wiring 43 is connected to the output terminal 41.
A wiring 44 is connected between SW 32 and SW 36, and the other end of the wiring 44 is connected to the output terminal 42.

A wiring 47 is connected between SW33 and SW37, and the other end of the wiring 47 is connected to the output terminal 45.
A wiring 48 is connected between SW 34 and SW 38, and the other end of the wiring 48 is connected to the output terminal 46.
The control unit 30 controls ON / OFF operation of the SWs 31 to 38 connected as described above, and controls charging of the capacitors 21 and 22 by the transformers 11 and 12.

  According to the heart stimulating device 3 according to this modification, a high-voltage second waveform pulse can be output from the output terminals 41 and 42 and a low-voltage first waveform pulse can be output from the output terminals 45 and 46. . Thus, by separating the output terminals of the first waveform pulse and the second waveform pulse, the electrodes connected to each output terminal can be arranged at different positions, and different positions can be stimulated by each pulse.

  Specifically, for example, the output terminals 41 and 42 are connected to an RV (right ventricle) defibrillation electrode, and the output terminals 45 and 46 are connected to a CS (coronary vein) defibrillation electrode or an SVC (upper aorta) defibrillation. Connect to the electrode. Thus, according to the heart stimulating device 3 according to this modification, stimulation by the first waveform pulse and the second waveform pulse can be performed at an appropriate position in the living body, and defibrillation can be performed effectively. Can do.

[Third Modification]
As a third modification of the heart stimulating apparatus 1 according to the present embodiment, as shown in FIG. 8, a plurality of capacitors are prepared to generate the first waveform pulse, and are alternately used for the output of the pulse. It is also possible to switch the capacitor to be switched.

  As shown in FIG. 8, the heart stimulating device 4 according to the present modification has a configuration similar to that of the heart stimulating device 1 described above (see FIG. 1), in addition to a transformer connected in parallel to the transformer 11 and the capacitor 21. 49, a capacitor 50, and a SW 51 for switching between the capacitor 21 and the capacitor 50 as a capacitor used for generating the first waveform pulse.

In the heart stimulating device 4 according to this modification, charges are accumulated in the capacitor 50 through the transformer 49. The SW 51 switches the connection between the capacitor 21 and the capacitor 50 and supplies a voltage to the SW 33 and SW 34.
Specifically, as shown in FIG. 9, when the first waveform pulse is output, the capacitor 21 is charged with the voltage of the first and third pulses, and the capacitor 50 is charged with the voltage of the second and fourth pulses. Charge.

Then, the control unit 30 controls the SW 51 so that the charges charged in the capacitor 21 and the capacitor 50 are output in different periods. Accordingly, the SW 51 outputs the electric charge charged in the capacitor 21 as the first waveform pulse in the first and third times of the first waveform pulse, and the electric charge charged in the capacitor 50 in the first waveform in the second and fourth times. Output as a pulse.
According to the heart stimulating device 4 according to the present modification having the above-described configuration, the charging time can be set longer for each of the capacitor 21 and the capacitor 50, so that a necessary pulse voltage can be reliably generated.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included. For example, you may apply this invention to embodiment which combined said embodiment and the modification suitably.

1, 2, 3, 4 Cardiac stimulator 10 Power supply 11, 12, 13, 49 Transformer (voltage application means)
21,50 capacitor (first capacitor)
22 Capacitor (second capacitor)
30 Control unit (control means)
31 to 38, 51 switch (pulse generation means)
41, 42 Output terminal (second output terminal)
45, 46 Output terminal (first output terminal)

Claims (6)

Pulse generating means for generating pulses for stimulating the heart;
A first capacitor for storing electric power for generating a first pulse by the pulse generating means;
A second capacitor for storing electric power for generating a second pulse having a voltage higher than that of the first pulse by the pulse generating means;
At least one voltage applying means for applying a voltage to each of the first capacitor and the second capacitor;
Control means for controlling the pulse generating means,
Prior to the output of the second pulse, the control means outputs the first pulse a plurality of times with a time interval, and the discharging period of the first capacitor and the charging period of the second capacitor A cardiac stimulating device that controls the pulse generating means so that the two overlap each other.   The cardiac stimulation apparatus according to claim 1, wherein the control means controls the pulse generation means so as to output the first pulse at a time interval shorter than a refractory period of the heart.   The cardiac stimulation apparatus according to claim 1 or 2, wherein the voltage applying means for applying a voltage to the first capacitor and the second capacitor is shared. A plurality of the first capacitors;
The cardiac stimulation device according to any one of claims 1 to 3, wherein the control unit controls the pulse generation unit so that discharge periods of the plurality of first capacitors are different.   The cardiac stimulation apparatus according to any one of claims 1 to 4, wherein the control unit controls the voltage marking unit to charge during at least a part of a stop period between the first pulses that are output in a plurality. . A first output terminal for outputting the first pulse;
The cardiac stimulation apparatus according to claim 1, further comprising a second output terminal that outputs the second pulse.

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