A system for implementing nanosecond ablation based on a low voltage platform

Abstract

This application discloses a system for nanosecond ablation based on a low-voltage platform, belonging to the field of pulse circuit control technology. It includes an upper full-bridge unit, a lower full-bridge unit, a load Rload, and a high-voltage power supply. The upper full-bridge unit includes a positive arm, a negative arm, and an output node Vo3. The lower full-bridge unit includes a positive arm, a negative arm, and an output node Vo4. The load Rload is connected between the output nodes Vo3 and Vo4 to achieve differential drive. When controlling under positive voltage, only the two transistors under positive voltage need to be considered, and when controlling under negative voltage, only the two transistors under negative voltage need to be considered. A common line is used, making the control logic simple and easy. For many high-voltage devices, the distance between them can be reduced, and the board area and machine size can be reduced.

Description

Technical Field

[0001] This application belongs to the field of pulse circuit control technology, specifically, it relates to a system for realizing nanosecond ablation based on a low-voltage platform. Background Technology

[0002] High-frequency pulsed ablation in catheter ablation is used to alter cell membrane permeability through an electric field. Once the transmembrane voltage threshold is reached, irreversible electroporation occurs. Traditional microsecond pulse width platforms are prone to creating irreversible electroporation under low pressure, but suffer from uneven ablation and missed cells blocked by nerves or blood vessels. Under low pressure conditions, especially in bipolar electrode scenarios, the rapid decline in transmembrane potential after its initial rise makes accumulation difficult, leading to bubble formation due to electrochemical reactions. The size of the bubble is almost directly proportional to the pulse width; the wider the pulse width, the larger the bubble. Large bubbles can cause embolism and other problems in patients. The ablation depth is also directly proportional to the pulse width; the wider the pulse width, the deeper the ablation.

[0003] Because the pulse width is narrowed, a very high voltage is required to achieve the ablation effect. The narrower the pulse width, the higher the voltage, which may exceed 10,000 volts. This can cause additional risks such as hemolysis. The apoptosis caused by ablation leads to a longer cell death time, making it difficult to identify the treatment effect in the short term. Summary of the Invention

[0004] To address the aforementioned problems and technical deficiencies, this application adopts the following technical solution: a system for realizing nanosecond ablation based on a low-voltage platform, characterized in that it includes an upper full-bridge unit, a lower full-bridge unit, a load Rload, and a high-voltage power supply. The upper full-bridge unit includes: positive arm, negative arm, and output node Vo3; The lower full-bridge unit includes: positive arm, negative arm, and output node Vo4; The load Rload is connected between output node Vo3 and output node Vo4 to achieve differential drive.

[0005] Preferably, the high-voltage power supply is divided into two parts, +HV and −HV, with adjustable voltage to achieve asymmetrical output.

[0006] Furthermore, the positive arm of the upper full-bridge unit includes: a body diode Q1, a body diode Q2, and a series diode D11; The negative arm of the upper full-bridge unit includes: body diode Q3, body diode Q4, and series diode D10.

[0007] Furthermore, the body diode Q1 is connected to the high-voltage power supply +HV, and the body diode Q2 is connected to GND; The body diode Q3 is connected to GND, and the body diode Q4 is connected to the high voltage power supply −HV.

[0008] Furthermore, the positive arm of the lower full-bridge unit includes: a body diode Q5, a body diode Q6, and a series diode D12; The negative arm of the lower full-bridge unit includes: body diode Q7, body diode Q8, and series diode D13.

[0009] Furthermore, the body diode Q5 is connected to the high-voltage power supply +HV, and the body diode Q6 is connected to GND. The body diode Q7 is connected to GND, and the body diode Q8 is connected to the high voltage power supply −HV.

[0010] Compared to existing technologies, the beneficial effects of this application are as follows: This application has positive, zero, and negative outputs on one output line, and the other line can be simply pulled to ground as a loop, or connected to another group of the same circuit to achieve voltage multiplication, asymmetric and other waveform outputs of positive and zero load voltage. When controlling with positive voltage, only the two transistors with positive voltage need to be considered, and when controlling with negative voltage, only the two transistors with negative voltage need to be considered. With one common line, the control logic is simple and easy. Compared to the traditional H-bridge, one output is positive voltage and the other is negative voltage. The voltage output to the load is positive voltage minus negative voltage, which is equivalent to voltage multiplication. However, the actual withstand voltage inside the machine is half of the output voltage. This allows for the reduction of the withstand voltage components and the space between them, as well as the reduction of the board area and machine size. By utilizing a low-voltage platform, it achieves advantages such as high and low frequency algorithm fitting, nanosecond pulse width, small bubbles, and deep ablation depth. Attached Figure Description

[0011] In the attached diagram: Figure 1 This is a schematic diagram of the circuit structure of an embodiment of this application; Figure 2 The following are specific waveform diagrams of embodiments of this application; Figure 3 This is a schematic diagram of a microsecond-level pulse width according to an embodiment of this application. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this application, but not all embodiments. Generally, the components of the embodiments of this application described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0013] Examples, such as Figure 1 As shown, a system for nanosecond ablation based on a low-voltage platform includes an upper full-bridge unit, a lower full-bridge unit, a load Rload, and a high-voltage power supply. The upper full-bridge unit includes: positive arm, negative arm, and output node Vo3; The lower full-bridge unit includes: positive arm, negative arm, and output node Vo4; The load Rload is connected between output node Vo3 and output node Vo4 to achieve differential drive.

[0014] The high-voltage power supply is divided into two parts, +HV and −HV, with adjustable voltage to achieve asymmetrical output.

[0015] The positive arm of the upper full-bridge unit includes: body diode Q1, body diode Q2, and series diode D11; The negative arm of the upper full-bridge unit includes: body diode Q3, body diode Q4, and series diode D10.

[0016] The body diode Q1 is connected to the high voltage power supply +HV, and the body diode Q2 is connected to GND. The body diode Q3 is connected to GND, and the body diode Q4 is connected to the high voltage power supply −HV.

[0017] The positive arm of the lower full-bridge unit includes: body diode Q5, body diode Q6, and series diode D12; The negative arm of the lower full-bridge unit includes: body diode Q7, body diode Q8, and series diode D13.

[0018] The body diode Q5 is connected to the high voltage power supply +HV, and the body diode Q6 is connected to GND. The body diode Q7 is connected to GND, and the body diode Q8 is connected to the high voltage power supply −HV.

[0019] Achieve changes in positive, zero, and negative polarity using a single common line.

[0020] By using symmetrical dual outputs, the final output achieves a voltage multiplier effect on the load, reducing the problem of increased machine size due to increased insulation distance.

[0021] The generation of the positive half-wave of the load by the body diodes Q1 and Q2: When the body diode Q1 (circled in green) is turned on, the other diodes are turned off, resulting in a positive voltage output. Then, when the body diode Q1 is turned off and the body diode Q2 is turned on, it is pulled to ground level. Then, the body diodes Q1 and Q2 alternately generate positive wave pulses such as positive voltage and zero; The negative half-wave of the load is generated by the body diodes Q3 and Q4. All others are turned off, and the body diode Q4 is turned on, resulting in a negative voltage output. Then, the body diodes Q4 and Q3 are turned on, and the negative voltage is pulled to zero level, thus alternately generating negative wave pulses. The purpose of adding the series diode D10 is to prevent the positive voltage from forming a short circuit to ground through the parasitic diode D3 with body diode Q3; The purpose of adding the series diode D11 is to prevent the negative voltage from being pulled to ground through the parasitic diode D2 of the body diode Q2 when the body diode Q4 is turned on, thus preventing a short circuit. Both diodes can be pulled to ground independently.

[0022] When output node V03 generates a positive pulse, output node V04 generates a negative pulse. At the load end, the voltage is superimposed. If output node V04 is 0 at this time, then the load voltage is neither amplified nor reduced. If the voltage of output node V04 is also positive at this time, then the voltage is also zero.

[0023] The nanosecond pulse width (tw) is 100ns~1000ns, the voltage range (Vo) is 500~3000V, the frequency (t) of a single positive or negative pulse is 200kHz~1MHz, and the frequency (T) of a combined positive and negative pulse is 10kHz~500kHz.

[0024] like Figure 2 As shown, based on the current PFA ablation voltage level of ≤2000V, and the fact that traditional bipolar nanosecond ablation requires higher voltage to achieve the ablation depth, the current microsecond PFA platform does not require higher voltage, and can even use lower voltage. By fitting the algorithm of high-frequency nanosecond waves, low-frequency high pulse width can be achieved, thereby achieving small bubbles and ablation depth.

[0025] Nanosecond pulses, compared to microseconds, can produce smaller bubbles, kill cells more uniformly within the tissue surface, and kill cells hidden around blood vessels or nerves, resulting in less hemolysis or other side effects.

[0026] pass Figure 3 The N T2 (ns) series in the lower part of the figure are fitted to obtain Figure 3 The function of the microsecond pulse width T1 in the upper middle figure.

[0027] The embodiments described above are merely preferred embodiments of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications, improvements, and substitutions without departing from the concept of this application, and these all fall within the protection scope of this application.

Claims

1. A system for nanosecond ablation based on a low-pressure platform, characterized in that, Includes upper full-bridge unit, lower full-bridge unit, load Rload, and high-voltage power supply; The upper full-bridge unit includes: positive arm, negative arm, and output node Vo3; The lower full-bridge unit includes: positive arm, negative arm, and output node Vo4; The load Rload is connected between output node Vo3 and output node Vo4 to achieve differential drive.

2. The system for nanosecond ablation based on a low-pressure platform according to claim 1, characterized in that, The high-voltage power supply is divided into two parts, +HV and −HV, with adjustable voltage to achieve asymmetrical output.

3. The system for nanosecond ablation based on a low-pressure platform according to claim 2, characterized in that, The positive arm of the upper full-bridge unit includes: a body diode Q1, a body diode Q2, and a series diode D11; The negative arm of the upper full-bridge unit includes: body diode Q3, body diode Q4, and series diode D10.

4. The system for nanosecond ablation based on a low-pressure platform according to claim 3, characterized in that, The body diode Q1 is connected to the high voltage power supply +HV, and the body diode Q2 is connected to GND. The body diode Q3 is connected to GND, and the body diode Q4 is connected to the high voltage power supply −HV.

5. The system for nanosecond ablation based on a low-pressure platform according to claim 2, characterized in that, The positive arm of the lower full-bridge unit includes: a body diode Q5, a body diode Q6, and a series diode D12; The negative arm of the lower full-bridge unit includes: body diode Q7, body diode Q8, and series diode D13.

6. The system for nanosecond ablation based on a low-pressure platform according to claim 5, characterized in that, The body diode Q5 is connected to the high voltage power supply +HV, and the body diode Q6 is connected to GND. The body diode Q7 is connected to GND, and the body diode Q8 is connected to the high voltage power supply −HV.

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