Implantable pulse generator with rectangular shock waveform

Abstract

The invention relates to an implantable pulse generator comprising a circuit, wherein the circuit comprises a main energy store, at least one secondary energy store and a control unit, wherein the control unit is configured to activate electrical switches in the circuit in such a way that in a first interval of a first phase of pulse delivery the main energy store is discharged via a therapy current path and in such a way that in a second interval of the first phase of pulse delivery the secondary energy store is discharged via the therapy current path, wherein the main energy store and the at least one secondary energy store are fixedly connected or connectable in series, and wherein the implantable pulse generator is designed to deliver electric shocks with an approximately rectangular pulse waveform.

Description

Technical Field

[0001] This invention relates to an implantable pulse generator. Background Technology

[0002] Currently, capacitor discharge is always used in implantable defibrillators (ICDs) for defibrillation, where all shock energy is drawn from a constant capacitor during defibrillation. This is characterized by an exponentially decreasing voltage waveform.

[0003] Shock waveforms that support minimized shock voltage are already in use in external defibrillators. Summary of the Invention

[0004] A disadvantage of exponential shock waveforms is the high peak voltage required to perform effective defibrillation. This is particularly true in the case of non-venous defibrillators (e.g., subcutaneous ICDS, such as S-ICDs). TM This can result in peak voltages exceeding 1300V, which in turn requires appropriate high-voltage components and compliance with consistent design rules.

[0005] Based on the above, one object of the present invention is to provide an implantable pulse generator that can provide therapeutically effective electric shocks using a lower shock voltage.

[0006] This objective is achieved by an implantable pulse generator having the features of claim 1 and a method having the features of claim 11. Suitable embodiments are provided in the dependent claims and the following description.

[0007] According to claim 1, an implantable pulse generator including a circuit is provided. The circuit includes:

[0008] -Main energy storage;

[0009] - At least one auxiliary energy storage device; and

[0010] - Control unit, wherein the control unit is configured to

[0011] • The electrical switch in the circuit is activated in such a manner that, during the first interval of the first stage of pulse delivery, the main energy storage discharges via the therapeutic current path, and

[0012] • The electrical switch in the circuit is activated in such a manner that, during the second interval of the first phase of pulse delivery, at least one auxiliary energy storage device discharges via the therapeutic current path.

[0013] The main energy storage device and at least one auxiliary energy storage device are fixedly connected or can be connected in series, and wherein...

[0014] The implantable pulse generator is designed to deliver an electric shock with an approximately rectangular pulse waveform, wherein

[0015] The implantable pulse generator includes multiple auxiliary energy storage devices, and

[0016] The control unit is also configured to activate the electrical switch in the circuit in such a way that, in the second interval, the main energy storage device and all auxiliary energy storage devices continuously discharge via the therapeutic current path, or

[0017] The main energy storage and, in each case, one of multiple auxiliary energy storages, are discharged via a therapeutic current path.

[0018] Specifically, the therapeutic current path is used to deliver therapeutic electrical pulses to target tissue, preferably the patient's cardiac tissue, and preferably for delivering therapeutic shocks for cardiac tissue defibrillation.

[0019] Furthermore, specifically, during the second interval of the first stage of pulse delivery, the main energy storage device and at least one auxiliary energy storage device are discharged via the therapeutic current path.

[0020] Advantageously, shock delivery with an approximately rectangular pulse waveform can be achieved using a pulse generator according to the invention, particularly with a substantially rectangular voltage or current waveform during pulse delivery. In this way, it is possible to deliver a therapeutically effective (defibrillation) pulse within a limited time while reducing the maximum required shock voltage. The method according to the invention advantageously allows for more cost-effective design of implantable defibrillators, as well as the use of existing high-voltage components and platforms, particularly by reducing the maximum required shock voltage.

[0021] Therefore, the implantable pulse generator according to the invention is particularly suitable for use as a cardiac cardioversion defibrillator, thereby enabling a therapeutic voltage of up to 1200V with the aforementioned rectangular pulse waveform via the circuit according to the invention. Thus, the pulse generator according to the invention can be positioned as one electrode pole, and the end of the electrode lead connected to the pulse generator can be positioned as another electrode pole outside the patient's chest cavity (subcutaneous ICD). Due to the potentially more compact design, the pulse generator configured as a subcutaneous ICD advantageously has a 70cm diameter. 3 Or even smaller in size.

[0022] Of course, a lower treatment voltage, such as 600V, can also be achieved using the pulse generator according to the invention. This allows for use as a conventional ICD, where the ends of the electrode leads are positioned inside the thoracic cavity, while the pulse generator is located outside the thoracic cavity. The aforementioned lower treatment voltage can be achieved with a smaller energy storage device. Due to the potentially more compact design, the pulse generator configured as a conventional ICD can correspondingly have a size of 35cm. 3 Or even smaller in size.

[0023] The pulse generator according to the invention can also be used in ICDs, wherein the ends of the electrode leads and the pulse generator are both located within the thoracic cavity. In this case, a treatment voltage of approximately 550V is preferably used, which is achieved using the pulse generator according to the invention, which includes a small energy storage device, thereby enabling, in particular, treatments up to 35cm. 2 Or a smaller device size.

[0024] According to one embodiment of the implantable pulse generator according to the invention, a main energy storage device and at least one auxiliary energy storage device are provided connected in series, particularly in a fixed or immutable series connection, that is, the energy storage devices are not disconnected by a switch. Due to this fixed series connection, the circuit according to the invention is advantageously less prone to failure.

[0025] According to an alternative embodiment of the implantable pulse generator, a main energy storage device and at least one auxiliary energy storage device are provided that can be connected in series.

[0026] According to one embodiment of the implantable pulse generator of the present invention, a discharge of at least one auxiliary energy storage device is provided in a time-controlled or signal-controlled manner.

[0027] In this process, control signals can be derived from the analysis of one or more measured voltages or currents, which are directly measured at the energy storage device or, for example, at the pulse delivered in the therapeutic current path.

[0028] Therefore, one embodiment of the implantable pulse generator according to the invention includes a device for voltage monitoring, which is particularly configured to preferably continuously or at predetermined intervals determine the voltage of each energy storage of the implantable pulse generator according to the invention.

[0029] The device for voltage monitoring is preferably also configured to send a first signal to the control unit when the voltage of one of the energy storage devices of the implantable pulse generator according to the invention drops below a predetermined threshold. The first signal can advantageously trigger the discharge of another energy storage device via a therapeutic current path.

[0030] The device for voltage monitoring is preferably also configured to send a second signal to the control unit when the voltage of one of the energy storage devices of the implantable pulse generator according to the invention does not drop below a predetermined threshold within a predetermined time. The second signal can advantageously suppress the discharge of the other energy storage device via the treatment current path. In this design, the device and control unit for voltage monitoring can implement an overvoltage protection system specifically for the circuit according to the invention. The presence (voltage drop) or absence (no voltage drop) of a load on the treatment current path is determined by voltage measurement. If no load is detected, no further energy storage discharges via the treatment current path, thus preventing further voltage increase in the treatment current path.

[0031] According to another embodiment, the implantable pulse generator according to the invention includes a device for measuring the impedance of surrounding tissue (body tissue). The device for impedance measurement is preferably configured to determine the resistance causing the discharge (observed by voltage drop) based on a voltage determined after the main energy storage device and / or at least one auxiliary energy storage device begins to discharge. This voltage can be a therapeutic voltage, the voltage of a separate energy storage device, or any voltage in the circuit according to the invention. In this process, the voltage can be determined by the device described above for voltage monitoring.

[0032] According to another embodiment of the implantable pulse generator according to the invention, a timing point for determining the start of the second interval of the first phase is provided based on the discharge behavior of the main energy storage device and / or at least one auxiliary energy storage device. The timing point is selected in such a way that the voltage of the specific energy storage device does not drop below a predetermined threshold (e.g., 80% of the output voltage).

[0033] According to another embodiment of the implantable pulse generator according to the invention, a circuit is provided comprising a plurality of auxiliary energy memories, wherein a control unit is configured to activate one or more electrical switches of the circuit in such a way that the auxiliary energy memories discharge sequentially or continuously via a therapeutic current path during a second interval of a first phase of pulse delivery.

[0034] According to another embodiment of the implantable pulse generator according to the invention, a main energy storage device and a plurality of auxiliary energy storage devices are provided in series connection, particularly in a fixed or immutable connection, that is, particularly in the absence of a disconnectable switch between the energy storage devices.

[0035] According to an alternative embodiment of the implantable pulse generator, a main energy storage device and each of a plurality of auxiliary energy storage devices are provided to be connected in series, wherein in particular the auxiliary energy storage devices can be connected in parallel with each other.

[0036] Specifically, multiple auxiliary energy storage devices can have substantially the same capacitance (i.e., within a tolerance of no more than 20%) and / or nominal voltage (i.e., within a tolerance of no more than 10%) or different capacitances and / or nominal voltages. In the case of multiple auxiliary energy storage devices, these auxiliary energy storage devices are preferably of the same or equivalent type in each case.

[0037] According to another embodiment of the implantable pulse generator according to the invention, in each case, one of the auxiliary energy storage devices is provided to discharge (alternatingly or entirely continuously) via a therapeutic current path at corresponding time points within a second interval. Similarly, the corresponding time points are preferably selected in such a way that the voltage of the specific energy storage device does not drop below a predetermined threshold (e.g., 80% of the output voltage). Likewise, the corresponding time points can be selected in such a way that the therapeutic voltage drop does not exceed 20% of the maximum voltage or the output voltage.

[0038] The discharge of one or more auxiliary energy receptacles in the therapeutic current path preferably occurs in such a manner that the actual pulse waveform (peak therapeutic voltage / current) differs from the desired ideal rectangular pulse waveform by less than 50%, preferably less than 20%. This difference is also referred to as a ripple. This is manifested as spikes in the voltage waveform.

[0039] As described above, the variation (ripple) can be kept within the aforementioned boundaries by voltage monitoring, where a voltage drop is observed as the exponential portion of the energy storage discharges. If the voltage drops below a predetermined threshold, the charge of another energy storage is invoked, where the treatment voltage increases to the desired maximum voltage and then decreases again as the other energy storage discharges. Further spikes or ripples in the voltage waveform also indicate this.

[0040] As mentioned above, the changes (ripples) or multiple changes can also be controlled in a time-controlled manner. The last auxiliary energy storage to which the charge is invoked is preferably discharged through a biphasic electric shock until the polarity is reversed (the last spike of the treatment voltage "decays" until the polarity of the shock is reversed).

[0041] The timing for switching to the next energy storage device can be determined, for example, from the exponential law of energy storage device discharge, with a known time constant, a known capacitance C, and a resistance R determined as described above: the charge of the activated energy storage device is equal to the first polarity (+ / -20%).

[0042] The ideal pulse waveform variation (ripple) or multiple variations can be controlled in such a way that each time the switch to the next energy storage device is made, the treatment voltage increases by approximately (+ / -20%) to the same voltage, that is, the peak value of the ripple is at the same level (+ / -20%).

[0043] As an alternative, one or more variations of the ideal pulse waveform can be monitored in such a way that the treatment voltage decreases each time the device switches to the next energy storage, for example, by up to 20% each time.

[0044] As described above, the control of one or more changes can be time-controlled or voltage-controlled.

[0045] According to another embodiment of the implantable pulse generator according to the invention, a control unit is provided that is further configured to activate at least one electrical switch of the circuit, preferably multiple switches of a bridge circuit (H-bridge), in a manner reversing the current direction in the therapeutic current path during the second phase of pulse delivery. This advantageously allows for a steep voltage drop in the pulse at the end of the first phase and enables the generation of biphasic therapeutic pulses. Furthermore, areas in the target tissue that were not adequately stimulated in the first phase can advantageously be stimulated in the second phase. Simultaneously, charge equalization can advantageously be achieved in the target tissue, preferably cardiac tissue.

[0046] According to another embodiment of the implantable pulse generator according to the invention, a control unit is also configured to, in the second stage of pulse delivery:

[0047] - The electrical switch in the circuit is activated in such a way that the main energy storage discharges via a therapeutic current path, or

[0048] - The electrical switches in the circuit are activated in such a way that the main energy storage and one or more auxiliary energy storages are discharged via a therapeutic current path.

[0049] According to an alternative embodiment of the implantable pulse generator according to the invention, a control unit is also provided to activate one or more electrical switches at the end of the first phase of pulse delivery in such a way that the main energy storage and / or auxiliary energy storage or multiple auxiliary energy storages are disconnected from the therapeutic current path, and / or discharged in one or more bleeder resistors connected thereto. Advantageously, in this embodiment, a steep voltage drop of the pulse can also be achieved at the end of the first phase, wherein a single-phase pulse can be generated during this process.

[0050] According to another embodiment of the implantable pulse generator according to the invention, a main energy storage device is provided comprising a plurality of individual energy storage devices connected in series or in parallel with each other. The number of individual energy storage devices is preferably adapted to the required or desired charging capacitance. The main energy storage device preferably comprises at least two individual energy storage devices, and more preferably three individual energy storage devices.

[0051] According to another embodiment of the implantable pulse generator according to the invention, a separate energy storage device of the main energy storage device is provided in a fixed series connection.

[0052] In particular, the individual energy storage units of the main energy storage unit may have substantially the same capacitance (i.e., within a tolerance of no more than 20%) and / or nominal voltage (i.e., within a tolerance of no more than 10%) or different capacitance and / or nominal voltage.

[0053] In another embodiment of the implantable pulse generator according to the invention, one or more switches of the circuit are electronic switches or semiconductor switches, particularly selected from: insulated-gate bipolar transistors (IGBTs), anode-gated thyristors (AGTs), or combinations of the above electronic switches.

[0054] According to another embodiment of the implantable pulse generator according to the invention, at least one of the aforementioned switches is electrically connected to a diode, wherein the diode is disposed between one of the energy storage devices and the switch. The diode is preferably configured to block current in the direction of the energy storage device. Except for the switch through which the last auxiliary energy storage device discharges via its therapeutic current path, the diode is preferably arranged between each switch and the associated energy storage device. Here, each diode is preferably configured to block current in that direction of the specific energy storage device. This advantageously protects the switch from polarity reversal.

[0055] According to another embodiment of the implantable pulse generator according to the invention, a plurality of auxiliary energy storage devices are provided, including two to four auxiliary energy storage devices, preferably three auxiliary energy storage devices.

[0056] According to one embodiment of the implantable pulse generator according to the invention, the energy storage device is provided as a capacitor or a coil. Multiple energy storage devices, such as multiple auxiliary energy storage devices, can be formed from capacitors in the process, the capacitors comprising multiple capacitances, for example formed from multiple anodes, wherein the multiple capacitances can discharge independently of each other.

[0057] According to another embodiment of the implantable pulse generator according to the invention, a plurality of auxiliary energy storage devices are provided, which are formed by capacitors, the capacitors including at least one first electrode having a first polarity and at least two second electrodes having a second polarity, wherein the first electrode and the at least two second electrodes can be electrically contacted separately from each other from the outside of the capacitor.

[0058] According to another embodiment of the implantable pulse generator according to the invention, a main energy storage device and / or one or more auxiliary energy storage devices are provided. The main energy storage device and / or one or more auxiliary energy storage devices are capacitors comprising at least one cathode and at least two anodes, preferably comprising three anodes, wherein the cathode and at least two anodes can be electrically contacted separately from the outside of the capacitor. The capacitor preferably comprises a conductive housing in which the cathode and anodes are arranged, wherein the housing is electrically connected to the cathode, and the anodes can be electrically contacted with each other via at least one feedthrough from the outside of the capacitor or the capacitor housing. The cathode is preferably formed of an electrolyte, wherein the anodes are preferably formed of a valve metal, preferably aluminum, tantalum, or niobium. In particular, each of the anodes can form a dedicated capacitor with the cathode (electrolyte), which is preferably in the range of 200 μF to 300 μF, particularly in the range of approximately 241 μF.

[0059] According to another embodiment of the implantable pulse generator according to the invention, a circuit is provided comprising a main energy memory and an auxiliary energy memory, the main energy memory comprising three capacitors including multiple electrodes as described in the preceding paragraph, and the auxiliary energy memory being formed by the capacitors described in the preceding paragraph, wherein, in particular, the capacitors configured as auxiliary energy memories comprise at least two, preferably three, anodes that can be electrically contacted independently of each other from the outside of the capacitors, and accordingly at least two, preferably three, capacitors that can discharge independently of each other can be formed.

[0060] According to another embodiment of the implantable pulse generator according to the invention, one or more capacitors are provided to form one of a main energy storage device, a separate energy storage device, or an auxiliary energy storage device described above. The one or more capacitors are electrolytic capacitors, ceramic capacitors, or film capacitors, preferably aluminum or tantalum electrolytic capacitors, and preferably have a capacitance of at least 5 J*cm. 3 Energy density.

[0061] According to one embodiment of the energy storage device according to the present invention, a

[0062] - The main energy storage device has a capacitance ranging from 150μF to 300μF and / or a nominal voltage ranging from 250V to 300V, and / or

[0063] - One or more auxiliary energy storage devices have independently of each other a capacitance in the range of 180μF to 36μF and / or a nominal voltage in the range of 250V to 255V.

[0064] If the main energy storage is formed by multiple separate energy storage devices, such as two or three, the main energy storage preferably has a total capacitance in the range of 150 μF to 300 μF.

[0065] According to claim 11, a method is provided for transmitting an electrical pulse having a basic rectangular pulse waveform. The method includes the following steps:

[0066] - During the first interval of the first stage of pulse delivery, the main energy storage device is connected to the discharge current path; and

[0067] - During the second interval of the first stage of pulse delivery, at least one charged auxiliary energy storage device is connected to the discharge current path.

[0068] The main energy storage device and at least one auxiliary energy storage device are fixedly connected or can be connected in series, and wherein...

[0069] - In the second interval, the main energy storage device and all auxiliary energy storage devices continuously discharge via the therapeutic current path, or

[0070] - The main energy storage and one of the multiple auxiliary energy storages in each case are discharged via the therapeutic current path.

[0071] The method according to the invention can be advantageously implemented by the implantable pulse generator according to claim 1 or one of the above embodiments.

[0072] According to one embodiment of the method according to the invention, a main energy storage device for charging and at least one auxiliary energy storage device for charging are provided to be fixedly connected in series, that is, in particular, not disconnected by a switch.

[0073] According to an alternative embodiment of the method according to the invention, a main energy storage device for charging and at least one auxiliary energy storage device for charging are provided to be connected in series.

[0074] According to one embodiment of the method according to the invention, the connection from at least one auxiliary energy storage device to the discharge current path is signal-controlled or time-controlled.

[0075] According to one embodiment of the method according to the invention, during a second interval of a first phase of pulse delivery, a plurality of charged auxiliary energy storage devices are sequentially or continuously connected to a discharge current path.

[0076] According to one embodiment of the method according to the invention, a main energy storage device for charging and a plurality of auxiliary energy storage devices for charging are provided to be fixedly connected in series, that is, in particular, not disconnected by a switch.

[0077] According to an alternative embodiment of the method according to the invention, a main energy storage device for charging and a plurality of auxiliary energy storage devices for charging are provided that can be connected in series.

[0078] According to one embodiment of the method according to the invention, only one auxiliary energy storage device is connected to the discharge current path at a time, wherein, particularly in each case, multiple charged auxiliary energy storage devices are connected sequentially to the discharge current path. This can be achieved, in particular, by a circuit in which the auxiliary energy storage devices can be connected in parallel with each other. Thus, only one auxiliary energy storage device and one main energy storage device are connected to the discharge current path at a time.

[0079] According to one embodiment of the method according to the invention, a plurality of charging auxiliary energy storage devices are provided sequentially connected to a discharge current path, wherein, in particular, all auxiliary energy storage devices are connected continuously to the discharge current path. This can be achieved, in particular, by a circuit in which the main energy storage device and the auxiliary energy storage devices are connected in series with each other. Thus, the main energy storage device, the first auxiliary energy storage device, and each of the other auxiliary energy storage devices are connected in series in the discharge current path.

[0080] According to another embodiment of the method according to the invention, a connection is provided between a main energy storage device and at least one or more auxiliary energy storage devices, in each case implemented by a switch, particularly by an electronic switch.

[0081] According to another embodiment of the method according to the invention, in the second stage of pulse delivery, the current direction in the current path is reversed. This reversal of the current direction can advantageously be achieved using a bridge circuit.

[0082] According to another embodiment of the method according to the invention, a second stage of pulse delivery is provided.

[0083] -Only the main energy storage is connected to the discharge current path, or

[0084] - The main energy storage and one or more auxiliary energy storages are connected to the discharge current path. Attached Figure Description

[0085] Further features and advantages of the invention will be described below with reference to the accompanying drawings of exemplary embodiments. In the drawings:

[0086] Figure 1 Various electrical shock waveforms from implantable defibrillators and their effects on the transmembrane voltage of cardiomyocytes are shown.

[0087] Figure 2(A) illustrates an embodiment of a circuit according to the present invention, which includes a main energy storage device and an auxiliary energy storage device that can be connected in series.

[0088] Figure 2(B) shows the associated voltage waveforms of the therapeutic voltage and energy storage (top panel), and their effect on the transmembrane voltage of cardiomyocytes (bottom panel); and

[0089] Figure 2(C) shows a detailed representation of the embodiment shown in Figure 2(A);

[0090] Figure 3(A) illustrates an alternative embodiment of the circuit according to the invention, which includes a main energy storage unit connected in series and an auxiliary energy storage unit connected in parallel; and

[0091] Figure 3(B) shows the relevant voltage waveforms of the treatment voltage and energy storage (top panel), and their effect on the transmembrane voltage of cardiomyocytes (bottom panel); and

[0092] Figure 4 An alternative embodiment of the circuit according to the invention is shown, using a capacitor comprising multiple anodes that are accessible from the outside. Detailed Implementation

[0093] Figure 1 The prior art state of the shock waveform for implantable defibrillators (suitable for transvenous and subcutaneous ICDs) is shown (top figure, blue). The therapeutic voltage is generated by the discharge of only one capacitor and therefore decreases exponentially. A disadvantage of this is that the process must begin with a fairly high initiation voltage to produce the same effect in the heart. For comparison, an ideal waveform (red) of a shock with a rectangular first phase is shown, along with a shock waveform of approximately a rectangular phase according to the method of the invention.

[0094] Figure 2A A preferred embodiment of the circuit according to the invention is shown, wherein energy storage devices C1 to C6 are capacitors connected or can be connected in series. Capacitors C1 to C3 forming the main energy storage device according to the invention can also be implemented as capacitor C0. All capacitors C1 to C6 can be charged simultaneously via a charging circuit. Switches S1 to S4 are switched sequentially in ascending order to deliver treatment. Switch i is opened again before switch i+1 is closed. The circuit also supplies power to an H-bridge for generating a second phase (not shown). One of the switches, preferably switch S4, is closed in the second phase. Instead of switch S4, a diode can also be provided to block current in the C0 / C4 direction. Figure 2B The top diagram shows the voltage waveform of the therapeutic voltage (blue) obtainable using this circuit, as well as the voltage waveforms at capacitors C0 (red), C4 (yellow), C5 (purple), and C6 (green). The bottom diagram shows the corresponding effect on the transmembrane voltage of cardiomyocytes. The main energy storage C0, formed by three separate energy storage devices C1 to C3, preferably has a total capacitance in the range of 150 μF to 300 μF, and each auxiliary energy storage device C4 to C6 preferably has a capacitance in the range of 180 μF to 360 μF.

[0095] Figure 2CIt shows Figure 2A The illustrated embodiment includes electronic switches and up to six capacitors, which serve as energy storage C1 to C6 for the pulse generator according to the invention. Three capacitors, C1, C2, and C3, ensure a sufficiently high start-up voltage, while the remaining three capacitors, C4, C5, and C6, generate the desired approximately rectangular pulse waveform (sawtooth curve), which in this example may have up to four spikes. To make the electric shock biphasic, an H circuit including electronic switches (IGBTs) Q05 to Q08 is typically used. This circuit provides feedback via electronic switches (IGBTs) Q01 to Q04, which activate capacitors C4, C5, and C6. Preferably, diodes D7 to D9 protect IGBTs Q02 to Q04 from polarity reversal. The electric shock is conducted into the body via terminals HV1 to HV2. The capacitors are charged via a high-voltage power supply connected to HVin and ground.

[0096] Figure 3A Another preferred embodiment of the circuit according to the invention is shown, which includes capacitors C1 to C6 as energy storage devices, wherein activated or activatable energy storage devices C4 to C6 are connected in parallel or can be connected to each other. Capacitors C1 to C3 can also be implemented as capacitor C0. All capacitors are charged simultaneously by a charging circuit. Switches S1 to S4 are switched sequentially in ascending order to deliver treatment. Switch i is opened again before switch i+1 is closed. The circuit also supplies power to an H-bridge for generating a second phase. One of the switches, preferably S1, is closed in the second phase. Figure 3B The top diagram shows the voltage waveform of the therapeutic voltage (blue) obtainable using the circuit, as well as the voltage waveforms at capacitors C0 (red), C4 (yellow), C5 (purple), and C6 (green), and the bottom diagram shows the corresponding effect on the transmembrane voltage of cardiomyocytes.

[0097] Figure 4 A preferred embodiment of the circuit according to the invention is shown, which includes a parallel method using capacitors comprising multiple anodes K, A1, A2, A3 as main energy storage devices C0, C1, C2, C3 and multiple auxiliary energy storage devices C4 to C6. Specifically, capacitors are used in this process, each capacitor comprising a cathode K and, for example, three anodes A1, A2, A3, wherein the cathode K can advantageously be externally contacted through a conductive casing, and the anodes can be externally contacted independently of each other and electrically insulated from each other and, for example, electrically insulated from the casing G via feed channels D1, D2, D3. Thus, the multiple auxiliary energy storage devices according to the invention are implemented as capacitors, providing three capacitances that can be discharged separately from each other through their three individually contacting anodes A1, A2, A3.

[0098] However, it is also conceivable that the capacitors C1 to C3 forming the main energy storage according to the invention are designed in such a way that the anodes A1, A2, A3 are electrically connected inside the housing G and can be electrically contacted from the outside via a shared anode line, which is wired to the outside, for example, via a feed channel.

Claims

1. An implantable pulse generator including circuitry, said circuitry comprising: -Main energy storage (C0); - At least one auxiliary energy storage device (C4, C5, C6); and - Control unit, the control unit is configured to • The electrical switches (S1, Q04) in the circuit are activated in such a manner that, during the first interval of the first stage of pulse delivery, the main energy storage device (C0) discharges via the therapeutic current path, wherein at least one auxiliary energy storage device does not discharge during the first interval, and • The electrical switches (S2, S3, S4, Q03, Q02, Q01) in the circuit are activated in the following manner: During the second interval of the first stage of pulse delivery, the main energy storage (C0) and at least one auxiliary energy storage (C4, C5, C6) discharge via the therapeutic current path. The main energy storage device (C0) and at least one auxiliary energy storage device (C4, C5, C6) are connected in series without any disconnectable switch between them. The implantable pulse generator is designed to deliver an electric shock with an approximately rectangular pulse waveform.

2. The implantable pulse generator according to claim 1, characterized in that, The circuit includes multiple auxiliary energy storage devices (C4, C5, C6), a main energy storage device (C0), and multiple auxiliary energy storage devices (C4, C5, C6) connected in series invariably, and the control unit is configured to activate one or more electrical switches (S2, S3, S4) of the circuit in such a way that the auxiliary energy storage devices (C4, C5, C6) discharge sequentially or continuously via a therapeutic current path during a second interval of the first phase of pulse delivery.

3. The implantable pulse generator according to claim 1 or 2, characterized in that, The control unit is also configured to activate at least one electrical switch in a manner that reverses the current direction in the therapeutic current path during the second phase of pulse delivery.

4. The implantable pulse generator according to claim 1 or 2, characterized in that, The main energy storage device (C0) includes multiple individual energy storage devices (C1, C2, C3), which are fixedly connected in series or can be connected in parallel with each other.

5. The implantable pulse generator according to claim 1 or 2, characterized in that, One or more switches (S1, S2, S3, S4, Q01, Q02, Q03, Q04, Q05, Q06, Q07, Q08) in the circuit are electronic switches.

6. The implantable pulse generator according to claim 1 or 2, characterized in that, The circuit includes two to four auxiliary energy storage devices.

7. The implantable pulse generator according to claim 1 or 2, characterized in that, The main energy storage device (C0) and / or one or more auxiliary energy storage devices (C4, C5, C6) are independent of each other and are capacitors or coils.

8. The implantable pulse generator according to claim 7, characterized in that, The plurality of auxiliary energy storage devices (C4, C5, C6) are formed by capacitors, each capacitor including at least one electrode (K) having a first polarity and at least two second electrodes (A1, A2, A3) having a second polarity, each electrode (K, A1, A2, A3) being electrically contacted separately from each other from the outside of the capacitor.

9. The implantable pulse generator according to claim 1 or 2, characterized in that... - The main energy storage (C0) has a capacitance in the range of 150 µF to 300 µF and / or a nominal voltage in the range of 250 V to 255 V, and / or - One or more auxiliary energy storage devices (C4, C5, C6) have independently capacities ranging from 180 µF to 360 µF and / or nominal voltages ranging from 250 V to 255 V.

10. A method for transmitting an electrical pulse having a basic rectangular voltage waveform (pulse waveform), comprising the following steps: - During the first interval of the first stage of pulse delivery, the main energy storage (C0) is connected to the discharge current path; as well as - In the second interval of the first stage of pulse delivery, multiple auxiliary energy storage devices (C4, C5, C6) are connected to the discharge current path. The main energy storage device (C0) and at least one auxiliary energy storage device (C4, C5, C6) are connected in series without any disconnectable switch between them. In the first interval, at least one auxiliary energy storage device does not discharge, and In the second interval, the main energy storage (C0) and all auxiliary energy storages (C4, C5, C6) are continuously discharged via the therapeutic current path.

11. The method according to claim 10, characterized in that, In the second interval of the first stage of pulse delivery, multiple auxiliary energy storage devices (C4, C5, C6) are connected to the discharge current path.

12. The method according to claim 11, characterized in that: - Only one auxiliary energy storage device (C4, C5, C6) is connected to the discharge current path at a time, or Multiple auxiliary energy storage devices (C4, C5, C6) are sequentially connected to the discharge current path.

13. The method according to any one of claims 10 to 12, characterized in that, In each case, the connection between the main energy storage device (C0) and at least one auxiliary energy storage device (C4, C5, C6) or multiple auxiliary energy storage devices (C4, C5, C6) is achieved by switches (S1, S2, S3, S4, Q01, Q02, Q03, Q04).

14. The method according to any one of claims 10 to 12, characterized in that, In the second stage of pulse delivery, the direction of the current in the therapeutic current path is reversed.

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