CN219021495U - Heart pulse electric field ablation system - Google Patents

Abstract

The utility model relates to a heart pulse electric field ablation system, belongs to the technical field of medical appliances, and solves the problem that the pulse edge generated by the existing high-voltage fast switch is not sharp enough. The system includes a high voltage output module, the high voltage output module including: a first branch comprising a first power switch and a second power switch connected in series; a second branch including a fifth power switch and a sixth power switch connected in series; an additional branch comprising a third power switch and a fourth power switch connected in series; the first branch, the additional branch and the second branch are sequentially connected in parallel between the direct-current high-voltage power supply and the grounding end; and a capacitor connected between a first node between the first power switch and the second power switch and a second node between the third power switch and the fourth power switch. The two groups of power switches SW3 and SW4 which are newly added in the 'field' bridge are matched with the corresponding time sequence control, so that the time of the rising edge and the falling edge of the high-voltage pulse can be effectively reduced.

Description

Heart pulse electric field ablation system

Technical Field

The utility model relates to the technical field of medical appliances, in particular to a heart pulse electric field ablation system.

Background

Pulsed electric field ablation is an emerging technology for treating atrial fibrillation, which utilizes a high-voltage pulsed electric field to act on tissues in heart chambers, and phospholipid bi-molecules of tissue cell membranes move and rearrange under the action of the pulsed electric field to form irreversible electroporation so as to further cause apoptosis, thereby achieving the purposes of eliminating and preventing abnormal potential transmission. Compared with radio frequency ablation and cryoablation, pulsed electric field ablation has the following characteristics: ablation is selective and does not damage surrounding tissue; the non-thermal energy ablation mode is basically free of thermal damage; the complication rate is very low; high ablation speed, low requirement for close contact, etc. Therefore, the pulsed electric field ablation has great application prospect in the aspect of atrial fibrillation treatment.

The high voltage pulse generator is an important part of the high voltage pulse electric field ablation system, but due to technical limitations, the pulse width, rising edge and falling edge time of the high voltage pulse generator are still to be further improved. In addition, bipolar high voltage pulses can produce higher intensity irreversible electroporation of biological tissue cells than unipolar positive or negative pulses, thereby enhancing the tissue ablation effect.

The high-voltage fast switch is a core component for generating high-voltage pulse, and the existing high-voltage fast switch has a circuit topology based on a single bridge and an H bridge. Fast switching circuits based on a single bridge can only produce single polarity positive or negative pulses. Fast switching circuits based on H-bridges are capable of generating bipolar pulses, but the pulse edges (rising and falling edges) they generate are typically relatively wide.

The high-voltage fast switching device/edge controllable high-voltage pulse power supply circuit can only generate unipolar pulses, and has an action effect inferior to bipolar high-voltage pulses in many application scenes. In addition, the rising edge and the falling edge of the existing high-voltage pulse signal have longer time.

Disclosure of Invention

In view of the above analysis, the present utility model is directed to a heart pulse electric field ablation system, which is used to solve the problem that the pulse edges (rising edge and falling edge) generated by the existing high-voltage fast switch are not sharp enough.

In one aspect, an embodiment of the present utility model provides a cardiac pulse electric field ablation system, including a high voltage output module, the high voltage output module including: a first branch comprising a first power switch and a second power switch connected in series; a second branch including a fifth power switch and a sixth power switch connected in series; an additional branch comprising a third power switch and a fourth power switch connected in series; the first branch, the additional branch and the second branch are sequentially connected in parallel between a direct-current high-voltage power supply and a grounding end; and a capacitor connected between a first node between the first power switch and the second power switch and a second node between the third power switch and the fourth power switch.

The beneficial effects of the technical scheme are as follows: the utility model is based on a novel 'field' bridge circuit structure, utilizes the power switch to charge the capacitor in the forward direction and in the reverse direction respectively, combines the principle that the voltages at the two ends of the capacitor cannot be suddenly changed, realizes bipolar high-voltage pulse output in the process of discharging the capacitor to the load, and has better effect in more application scenes compared with unipolar pulse output. Compared with the existing single bridge and H bridge, the two groups of power switches SW3 and SW4 which are newly added in the 'field' bridge are matched with the corresponding time sequence control, so that the time of the rising edge and the falling edge of the high-voltage pulse can be effectively reduced, and the power switch is more suitable for application scenes with more strict requirements on output performance; and the jitter phenomenon of the high-voltage pulse in the output process can be effectively reduced, so that the stability of load output is improved.

Based on the further improvement of the device, the heart pulse electric field ablation system further comprises: the direct-current low-voltage power supply module is electrically connected with the direct-current high-voltage power supply module, the control device, the high-voltage output module and the input end of the touch screen in the ablation host; the output end of the direct-current high-voltage power supply module is electrically connected with the high-voltage power supply input end of the high-voltage output module; the control device is connected with each output end of the ablation host computer to detect each output parameter in real time and generate a control signal according to each output parameter; the high-voltage output module is used for converting the direct-current high voltage into high-voltage pulses according to the control signals, and the high-voltage pulse output end of the high-voltage output module is electrically connected to ablation catheters of different models; and the touch screen is connected with the control device and used for displaying various output parameters detected in real time in a data or graphic mode.

Based on a further improvement of the device, the ablation catheter comprises a connecting part, an ablation part and an operation part between the ablation part and the connecting part, wherein the connecting part comprises an electric plug, a peripheral sheath and a luer connector, and the electric plug is used for electrically connecting the ablation catheter with the ablation host and conducting high-voltage pulses of the ablation host to an ablation electrode of an ablation unit; the luer connector is used for being connected with an external device to realize air intake, air suction, physiological saline delivery, contrast agent delivery and superfluous blood discharge of the ablation catheter; the ablation component comprises an ablation unit, a lead, an inner tube and an outer tube, wherein a plurality of ablation electrodes are fixed on the ablation unit and are used for applying the high-voltage pulse to pre-ablated tissue in the heart; and the operating member includes a handle, an inner tube, and an outer tube.

Based on the further improvement of the device, the handle is provided with a bending adjusting mechanism and a telescopic deformation adjusting mechanism of the ablation unit, wherein the bending adjusting mechanism is used for adjusting the bending degree of the ablation part, so that the ablation part can realize the adjustment of two degrees of freedom, and each degree of freedom can realize at least a bending angle of 60 degrees; the expansion deformation adjusting mechanism is used for adjusting the contraction and expansion of the ablation unit, and the ablation unit is in a contracted state when the ablation unit does not reach a pre-ablated tissue area yet; when the ablation unit has reached the pre-ablated tissue region, the ablation unit is in a deployed state while the ablation electrode at the ablation unit is deployed such that the ablation electrode is in contact with the pre-ablated tissue to apply the high voltage pulse to the pre-ablated tissue.

Based on the further improvement of the device, the heart pulse electric field ablation system further comprises: a current limiting resistor connected between the capacitor and the second node; and a load resistor connected between the second node and a third node between the fifth power switch and the sixth power switch.

Based on the further improvement of the device, the heart pulse electric field ablation system further comprises a first power switch, a second power switch, a third power switch and a fourth power switch, wherein the first power switch and the second power switch are used for generating bipolar high-voltage pulses according to the control signals, and the control device comprises a programmable gate array FPGA, a singlechip, a digital signal processing unit DSP, a central processing unit CPU or a signal generator.

Based on a further improvement of the above apparatus, each of the first to sixth power switches includes: the power supply device comprises a first isolation module, a second isolation module, a driving circuit and a power tube, wherein the output end of the first isolation module is connected to the input end of the driving circuit; the output end of the second isolation module is connected with the power input end of the first isolation module through a direct current-direct current module; and the output end of the driving circuit is connected to the grid electrode of the power tube.

Based on a further development of the above device, the first isolation module and the second isolation module each comprise a photovoltaic isolation, a magnetic isolation or a transformer isolation.

Based on the further improvement of the device, the power tube comprises a metal oxide semiconductor field effect transistor MOSFET, an insulated gate bipolar transistor IGBT, a bipolar junction transistor BJT, a junction field effect transistor JET and a high electron mobility transistor HEMT.

Based on a further improvement of the above device, the heart pulse electric field ablation system further comprises a reverse diode for parallel connection with the power tube, wherein the reverse diode comprises a zener diode or a transient voltage suppression diode.

Compared with the prior art, the utility model has at least one of the following beneficial effects:

1. the utility model is based on a novel 'field' bridge circuit structure, utilizes the power switch to respectively charge the capacitor in the forward direction and the reverse direction, combines the principle that the voltages at the two ends of the capacitor cannot be suddenly changed, realizes bipolar high-voltage pulse output in the process of discharging the load by the capacitor, has better tissue ablation effect in more application scenes compared with unipolar pulse output, and has more lasting ablation effect.

2. Compared with the existing single bridge and H bridge, the two groups of power switches SW3 and SW4 which are newly added in the 'field' bridge are matched with the corresponding time sequence control, so that the time of the rising edge and the falling edge of the high-voltage pulse can be effectively reduced, and the power switch is more suitable for application scenes with more strict requirements on output performance; and the jitter phenomenon of the high-voltage pulse in the output process can be effectively reduced, so that the stability of load output is improved.

3. According to the utility model, the first isolation module is used for carrying out good electric isolation on the low-voltage control signal and the high-voltage pulse output, and each power tube is subjected to voltage division protection through the reverse diode and the large resistor, so that the safety and stability of the whole circuit are effectively improved, and the high-voltage pulse output circuit is more suitable for application in the field of medical appliances.

4. The utility model designs accurate time sequence control of each group of power switches based on 6 groups of power switches in a field bridge circuit structure, so that the circuit can effectively reduce the time of rising edges and falling edges of high-voltage pulses. Based on the design, the utility model can realize the rising edge and the falling edge of the ultra-fast high-voltage pulse in the picosecond level, and the phospholipid bilayer of the cell membrane is easier to be opened by generating an ultra-fast changing pulse electric field. On the premise of generating the same ablation effect, the pulse voltage and the pulse dosage of the 'field' bridge circuit structure can be smaller, so that the safety in the pulse electric field ablation operation process is improved, and the design difficulty of a pulse electric field ablation host and a catheter is reduced.

5. The utility model is based on the specific time sequence control of the 'field' bridge circuit structure and the power switch, and can realize nanosecond ultra-short pulse width output. The method ensures that the ablated tissue hardly generates heat in the pulse electric field ablation process, thereby increasing the safety of the ablation process and reducing the occurrence probability of postoperative complications. In addition, based on nanosecond ultra-short pulse width output, the high-voltage pulse electric field ablation system disclosed by the utility model can realize the effect of not influencing normal heart rate activities without depending on an electrocardio synchronization function in an ablation process.

6. The utility model is based on the innovative 'field' bridge circuit structure, can realize ultra-fast rising edge and falling edge and ultra-short pulse width, and can realize the effect through common electronic components and chips without depending on high-end expensive electronic components and chips.

In the utility model, the technical schemes can be mutually combined to realize more preferable combination schemes. Additional features and advantages of the utility model will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the utility model. The objectives and other advantages of the utility model may be realized and attained by the structure particularly pointed out in the written description and drawings.

Drawings

The drawings are only for purposes of illustrating particular embodiments and are not to be construed as limiting the utility model, like reference numerals being used to refer to like parts throughout the several views.

FIG. 1 is a schematic circuit diagram of a high voltage fast switch according to an embodiment of the present utility model;

FIG. 2 is a diagram of a high voltage pulsed electric field ablation host in accordance with an embodiment of the present utility model;

FIGS. 3a and 3b are block diagrams of a high voltage pulsed electric field ablation catheter in accordance with an embodiment of the present utility model;

FIG. 4 is a specific configuration of a power switch according to an embodiment of the present utility model;

FIG. 5 is a timing diagram of a power switch and output waveforms according to an embodiment of the present utility model;

FIG. 6 is a bipolar high voltage pulse output waveform according to an embodiment of the present utility model; and

fig. 7 is a positive pulse output waveform according to an embodiment of the present utility model.

Detailed Description

Preferred embodiments of the present utility model will now be described in detail with reference to the accompanying drawings, which form a part hereof, and together with the description serve to explain the principles of the utility model, and are not intended to limit the scope of the utility model.

Referring to fig. 1, in one embodiment of the present utility model, a heart pulse electric field ablation system is disclosed, comprising a high voltage output module comprising: the first branch comprises a first power switch SW1 and a second power switch SW2 connected in series; the second branch comprises a fifth power switch SW5 and a sixth power switch SW6 connected in series; the additional branch comprises a third power switch SW3 and a fourth power switch SW4 connected in series; the first branch, the additional branch and the second branch are sequentially connected in parallel between the direct-current high-voltage power supply VCC and the ground GND; and a capacitor C is connected between a first node between the first power switch SW1 and the second power switch SW2 and a second node between the third power switch SW3 and the fourth power switch SW 4.

Compared with the prior art, the bipolar high-voltage pulse output device is based on a novel 'field' bridge circuit structure, utilizes the power switch to charge the capacitor in the forward direction and in the reverse direction respectively, combines the principle that the voltages at two ends of the capacitor cannot be suddenly changed, realizes bipolar high-voltage pulse output in the process of discharging the capacitor to a load, and has better effect in more application scenes compared with unipolar pulse output. Compared with the existing single bridge and H bridge, the two groups of power switches SW3 and SW4 which are newly added in the 'field' bridge are matched with the corresponding time sequence control, so that the time of the rising edge and the falling edge of the high-voltage pulse can be effectively reduced, and the power switch is more suitable for application scenes with more strict requirements on output performance; and the jitter phenomenon of the high-voltage pulse in the output process can be effectively reduced, so that the stability of load output is improved.

Hereinafter, a heart pulse electric field ablation system according to an embodiment of the present utility model will be described in detail with reference to fig. 1. The heart pulse electric field ablation system includes: a dc low voltage power module 212, a dc high voltage power module 210, a control device 208, a high voltage output module 206, a touch screen 202, and an ablation catheter.

The high voltage output module 206 includes: first branch, second branch, additional branch, capacitor C, current limiting resistor R _lim Load resistor R _load And a reverse diode. Referring to fig. 1, the first branch includes a first power switch SW1 and a second power switch SW2 connected in series; a second branch including a fifth power switch SW5 and a sixth power switch SW6 connected in series; an additional branch including a third power switch SW3 and a fourth power switch SW4 connected in series; the first branch, the additional branch and the second branch are sequentially connected in parallel between the direct-current high-voltage power supply VCC and the ground GND; and a capacitor C connected between a first node between the first power switch SW1 and the second power switch SW2 and a second node between the third power switch SW3 and the fourth power switch SW 4.

The first to sixth power switches SW1 to SW6 are used for generating bipolar high voltage pulses according to control signals, wherein the control device 208 includes a programmable gate array FPGA, a single chip microcomputer, a digital signal processing unit DSP, a central processing unit CPU or a signal generator. Each of the first to sixth power switches SW1 to SW6 includes: the power supply comprises a first isolation module, a second isolation module, a driving circuit and a power tube. The power transistor includes a metal oxide semiconductor field effect transistor MOSFET, an insulated gate bipolar transistor IGBT, a bipolar junction transistor BJT, a junction field effect transistor JEET, and a high electron mobility transistor HEMT.

Current limiting resistor R _lim Connected between the capacitor C and the second node; load resistor R _load A third node connected between the second node and the fifth power switch SW5 and the sixth power switch SW5Between the points. The reverse diode is used for being connected with the power tube in parallel, wherein the reverse diode comprises a zener diode or a transient voltage suppression diode.

Referring to fig. 4, the output of the first isolation module 402 (i.e., isolation module 1) is connected to the input of the driving circuit 408; the output of the second isolation module 404 (i.e., isolation module 2) is connected to the power input of the first isolation module 402 via a dc-to-dc module 406 (i.e., dc-to-dc); and a driving circuit 408, the output of which is connected to the gate of the power tube. The first isolation module 402 and the second isolation module 404 each include an opto-electrical isolator, a magnetic isolator, or a transformer isolator.

The dc low voltage power supply module 212 is electrically connected to the dc high voltage power supply module 210, the control device 208, the high voltage output module 206, and the low voltage power supply input of the touch screen 202 within the ablation host. The output of the dc high voltage power supply module 210 is electrically connected to the high voltage power supply input of the high voltage output module 206. The control device 208 is connected to each output of the ablation host to detect each output parameter in real time and generate a control signal according to each output parameter. The high voltage output module 206 is used for converting direct current high voltage into high voltage pulse according to the control signal, and the high voltage pulse output end of the high voltage output module is electrically connected to ablation catheters of different models. The touch screen 202 is connected to the control device 208, and displays various output parameters detected in real time in a data or graphic manner. The ablation host is connected to the ablation catheter via catheter interface 204.

Referring to fig. 3a and 3b, the ablation catheter includes a connecting member 302, an operating member 306, and an operating member 304 interposed between the operating member 306 and the connecting member 302. The connecting part 302 comprises an electric plug 308, a peripheral sheath 310 and a luer connector 312, wherein the electric plug 308 is used for electrically connecting an ablation catheter with an ablation host and conducting high-voltage pulse of the ablation host to an ablation electrode of an ablation unit; luer fitting 312 for connection with an external device to effect aspiration, delivery of saline, delivery of contrast agent, and evacuation of excess blood from the ablation catheter; the operation component 306 comprises an ablation unit 322, a lead 320, an inner tube 318 and an outer tube 316, wherein a plurality of ablation electrodes 324 are fixed on the ablation unit 322 and are used for applying high-voltage pulses to pre-ablated tissue in the heart; and the operating member 304 includes a handle 314, an inner tube 318 and an outer tube 316.

The handle 314 is provided with a bending adjustment mechanism and a telescopic deformation adjustment mechanism of the ablation unit 322, wherein the bending adjustment mechanism is used for adjusting the bending degree of the operation component 306, so that the operation component 306 realizes adjustment of two degrees of freedom, and each degree of freedom at least realizes a bending angle of 60 degrees; and a telescoping deformation adjustment mechanism for adjusting contraction and expansion of the ablation unit 322, wherein the ablation unit 322 is in a contracted state when the ablation unit 322 has not reached the pre-ablated tissue region; when the ablation unit 322 has reached the pre-ablated tissue region, the ablation unit 322 is in the deployed state while the ablation electrode 324 at the ablation unit 322 is deployed such that the ablation electrode 324 is in contact with the pre-ablated tissue to apply a high voltage pulse to the pre-ablated tissue.

Hereinafter, a heart pulse electric field ablation system according to an embodiment of the present utility model will be described in detail by way of specific examples with reference to fig. 1 to 7.

The core technology of the utility model is as follows: (1) the control circuit adopts a novel 'field' bridge circuit to realize bipolar high-voltage pulse output. (2) The field bridge is composed of a plurality of groups of power switches, and ultra-short high-voltage pulse width can be realized by matching with the specific time sequence control of each group of switches. (3) In addition, the field bridge circuit structure can realize ultra-fast pulse rising edge and falling edge.

Fig. 2 is a diagram of a high voltage pulsed electric field ablation host computer according to the present utility model. The pulsed electric field ablation host is mainly composed of a direct current power supply module 212, a direct current high voltage power supply module 210, a control device 208, a high voltage output module 206, a touch screen 202 and the like. The mains power supplies power to the dc power supply module 212 via the ac power outlet 214. In particular, two fuses and medical power filters are provided between the ac power outlet 214 and the dc power supply module 212 to provide network power short circuit protection and reduce network power output ripple. The dc low voltage power supply module 212 in the host has a plurality of sub-modules that respectively supply power to the dc high voltage power supply module 210, the control device 208, the high voltage output module 206, the touch screen 202, etc. within the host. The dc high voltage power module 210 provides the high voltage power to the high voltage output module 206, and the control device 208 controls the high voltage power to output at different amplitudes, polarities, times, frequencies, pulse widths, rising edges, falling edges, and duty ratios through a program. The operator can set various output parameters through the touch screen 202, and the control device 208 detects various output parameters of the host in real time and displays the parameters on the touch screen 202 in a data or graphic mode. The high voltage output module 206 has a plurality of high voltage pulse output interfaces for providing high voltage pulse output for ablation catheters of different gauges.

In order to ensure the stability and safety of the operation of the high-voltage pulse electric field ablation system, before the operation of the high-voltage pulse electric field ablation host, the host can perform a series of self-checking measures, and when the system is found to have abnormal functions or abnormal connection, the host can perform visual and audible alarm prompt through the touch screen 202; in the process of the high-voltage pulse electric field ablation host machine working, the host machine can detect the working state of each circuit board and the conductivity of the ablation catheter in real time, and when the condition that the host machine circuit board is abnormal in working or the ablation catheter is short-circuited or broken is found, the host machine can carry out visual and audible alarm prompt through the touch screen 202; after the high-voltage pulse electric field ablation host machine finishes working, when the power button is turned off, the host machine will perform self-discharge of the whole machine, so that the voltage in some energy storage components is released, and the risk of accidental electric shock of operators is reduced; in particular, the self-discharging function of the whole machine can be performed in the working process of the host machine, so that some emergency conditions can be dealt with, and the safety of personnel in the whole operation process is ensured.

Fig. 3a and 3b are block diagrams of a high voltage pulsed electric field ablation catheter of the present utility model. The ablation catheter is comprised of an operating member 306, an operating member 304, and a connecting member 302. Wherein the operating member 306 is comprised of an ablation unit 322, a guide wire 320, an inner tube 318 and an outer tube 316. A plurality of ablation electrodes 324 are fixed to the ablation unit 322 for applying high voltage pulse output to the pre-ablated tissue. The operating member 304 is composed of a handle 314, an inner tube 318 and an outer tube 316. The handle 314 is provided with a bending mechanism and a telescopic deformation adjusting mechanism of the ablation unit 322. The bending adjustment mechanism is used for adjusting the bending degree of the operation component 306, and the operation component 306 can at least realize two degrees of freedom adjustment, and each degree of freedom can at least realize a bending angle of 60 degrees. The telescopic deformation adjusting mechanism of the ablation unit 322 is used for adjusting the contraction and expansion of the ablation unit 322, and when the ablation unit 322 does not reach the pre-ablated tissue area yet, the ablation unit 322 is in a contracted state, and the outer diameter of the part is equal to the diameter of the outer tube 316 of the operation part 306; when the ablation unit 322 reaches the pre-ablated tissue area, the ablation unit 322 is in a unfolding state, and simultaneously, along with the unfolding of the ablation electrode 324 at the ablation unit 322, the ablation electrode 324 is contacted with the pre-ablated tissue at the moment, and then high-voltage pulse output is applied, so that the ablation of the tissue can be realized. The connection member 302 is comprised of an electrical plug 308, a peripheral sheath 310, and a luer 312. The electrical plug 308 is the electrical connection portion of the ablation catheter to the ablation host for conducting the high voltage pulse output of the ablation host to the ablation electrode 324 of the ablation unit 322. Luer 312 is used to connect some external device to perform functions such as ablation catheter intake, aspiration, saline delivery, contrast media delivery, and excess blood removal.

Fig. 1 is a schematic circuit diagram of a "field" bridge high voltage fast switch in the high voltage output module 206. Wherein VCC is a DC high voltage power supply generated by the DC high voltage power supply module 210, SW1, SW2, SW3, SW4, SW5 and SW6 are the 6 groups of power switches, C is a capacitor, R _load Ablation catheter for load resistance, i.e. high voltage pulsed electric field as shown in fig. 3a, R _lim The current limiting resistor is used for overcurrent protection of the whole circuit. Unlike single-bridge and H-bridge circuits, a capacitor C is added to the "field" bridge circuit. During the capacitor charging process, the voltage across the capacitor is maintained at a certain value (e.g., + VCC or-VCC); in the discharging process of the capacitor, the power switch is controlled to suddenly pull the potential of one end of the capacitor to 0 (i.e. GND shown in FIG. 1), and the principle that the voltage at two ends of the capacitor cannot be suddenly changed is utilized, and the potential at the other end of the capacitor becomes-VCC or +VCC at the moment, so that the sudden change of the voltage polarity at one end of the load is realized. In particular, the time taken for the abrupt change in potential due to the characteristic of capacitance can be controlled within picoseconds, therebyCan realize ultra-fast high-voltage pulse leading edge.

In addition, the power switches SW3 and SW4 incorporated in the "field" bridge circuit can provide for a load resistance R when needed _load The potential at the left end is forced to pull to 0 or +vcc, which plays a critical role in reducing the trailing edge time of the high voltage pulse and maintaining the stability of the output pulse. Based on the principle, 6 groups of power switches in the field bridge circuit can realize the load resistance R by utilizing respective specific time sequence control and matching with the inherent characteristic of the capacitor _load The positive and negative pulses with stable ends are output, and ultra-fast pulse rising edge, falling edge and ultra-short pulse width can be realized. In particular, in view of the stability and safety of the "field" bridge circuit, each group of power switches SW is composed of 2 or more power transistors in series, the capacitor C is composed of 2 or more capacitors in series, and the load resistor R _load Is composed of 4 or more resistors connected in series and parallel, the current-limiting resistor R _lim Consists of 4 or more resistors connected in series and parallel.

Fig. 4 shows a specific circuit structure of the single group of power switches SW. Each group of power switches SW is composed of 2 or more power transistors 410 connected in series, and each power transistor is controlled by a control signal P1, P2 generated by an isolation circuit, and P3 generated by a driving circuit 408. V (V) _I1 V is the input power to the first isolation module 402 _O1 Is the output power of the first isolation module 402. V (V) _I2 Is the input power to the second isolation module 404, which generates an isolated output V _O2 On the one hand, power is supplied to the driving circuit 408; on the other hand V _O2 Generating V through DC-DC module 406 _O1 For powering the isolated output of the first isolation module 402. Input power V of the first isolation module 402 _I1 Input power V of the second isolation module 404 _I2 And the control signal P1 corresponds to the ground DGND (digital ground), the output power V of the first isolation module 402 _O1 Output power V of the second isolation module 404 _O2 The ground corresponding to the control signal P2, the driving circuit 408, and the control signal P3 is AGND (analog ground). The control signal P1 is generated by an external micro-control processing unit, a first intervalInput power V from module 402 _I1 And input power V of the second isolation module 404 _I2 Is supplied by an external direct current power supply. In particular, since the two ends of the power tube 410 have a large voltage when they are turned off, a large current is generated at the moment of turning on, and thus, in order to protect the power tube 410, each power tube is connected with a reverse diode and a large resistor in parallel.

FIG. 5 shows the specific timing and load resistance R of the 6-group power switches SW (SW 1 to SW 6) _load Output waveform at both ends (V _O ). Where H represents the power switch SW in the closed state and L represents the power switch SW in the open state. A complete pulse output cycle includes 7 switching control phases ((1), (2), (3), (4), (5), (6) and (7)), each of which generates a high voltage negative pulse and a high voltage positive pulse. The working principle of the high-voltage fast switching circuit of the field bridge of the utility model for generating bipolar high-voltage pulses, stabilizing load voltage and having ultra-fast pulse rising edges and falling edges is described with reference to fig. 1 and 5.

Stage (1): SW1 and SW6 are closed, SW2, SW3, SW4 and SW5 are opened, and at this time, the dc high voltage power VCC charges the capacitor C in the forward direction. The potential at the left end of the capacitor C at the stage is +VCC, the potential at the right end of the capacitor C at the stage is 0, the voltage difference between the left end and the right end is +VCC, and the load resistor R _load The electric potential at the left and right ends is 0, and output V _O Is 0.

Stage (2): SW2 and SW6 are closed, SW1, SW3, SW4 and SW5 are opened, and capacitor C is connected to load resistor R _load And (5) discharging. The potential at the left end of the capacitor C is pulled to 0 in this stage, but the voltage at the left end and the right end of the capacitor C can not be suddenly changed and still is +VCC, so that the potential at the right end of the capacitor C becomes-VCC. Correspondingly, the load resistance R _load The left side potential is-VCC, the right side potential is 0, thus outputting V _O A pulse of-VCC is generated. The leading edge (falling edge) time of the negative pulse generated here is related to the capacitance characteristic, and the trailing edge (rising edge) time is related to the time when the capacitance C is recharged.

Stage (3): SW2, SW4 and SW6 are closed, and SW1, SW3 and SW5 are open. At this time, the load resistance R _load Left and right end potentialsAll 0. This phase uses the characteristics of the "field" bridge circuit, at which point SW4 is closed, on the one hand, enabling the load resistor R to be closed _load The potential at the left end is forced to pull 0, at which time the load resistor R _load The potential at the right end is 0, and the output V can be forcedly outputted at this stage _O Pulled to 0, thereby reducing V _O Rise (negative pulse trailing edge) time of (a) a (n) pulse. On the other hand, in the process that the capacitor C needs to be reversely charged in the later stage, the load resistor R _load The right-hand potential will rise if at this point the load resistance R _load The load resistor R during the reverse charging process if the left-side potential is still-VCC _load The voltage across it may create a large jitter condition. The utility model uses the unique characteristics of the field bridge circuit to close SW4 in the stage (3) so as to advance the load resistance R _load The left end potential is pulled to 0, so that the phenomenon of jitter generated by output can be effectively weakened.

Stage (4): SW2, SW3 and SW5 are closed, SW1, SW4 and SW6 are opened, and at this time, the dc high voltage power VCC reversely charges the capacitor C. The potential at the left end of the capacitor C at this stage is 0, the potential at the right end is +VCC, the voltage difference between the left end and the right end is-VCC, and the load resistor R _load The potentials of the left end and the right end are +VCC, and output V _O Is 0. This stage also takes advantage of the characteristics of the "field" bridge circuit, at which point SW3 is closed in order to let the load resistor R _load The left-side potential is forced to rise from 0 to +vcc. Due to the load resistance R during the reverse charging of the capacitor C _load The right-hand potential is +VCC, if the load resistor R is _load The load resistor R at this point in time, if the left-hand potential remains at 0 _load A negative pulse may be generated at both ends, thereby affecting the output V _O Is stable. The utility model uses the unique characteristics of the field bridge circuit to close SW3 in the stage (4), and when the capacitor C is reversely charged, the resistor R is used as the load _load The right-side potential rises to +VCC and simultaneously also loads the resistor R _load The potential at the left end rises to +vcc, thereby effectively preventing the phenomenon that the output is dithered at this time.

Stage (5): SW2 and SW6 are closed and SW1, SW3, SW4 and SW5 are openedCapacitor C versus load resistance R _load And (5) discharging. The left end potential of the capacitor C is 0 and the right end potential is +VCC in the stage. Correspondingly, the load resistance R _load The left side potential is +VCC and the right side potential is 0, thus outputting V _O A + VCC pulse is generated. The leading edge (rising edge) time of the positive pulse generated here is related to the capacitance characteristics and the trailing edge (falling edge) time is related to the time when the capacitance C is recharged.

Stage (6): SW2, SW4 and SW6 are closed, and SW1, SW3 and SW5 are open. At this time, the load resistance R _load The potential at both the left and right ends is 0. This stage again makes use of the characteristics of the "field" bridge circuit, at which point SW4 is closed, on the one hand enabling the load resistor R _load The left-side potential is forced to pull 0, at which time the load resistor R _load The potential at the right end is 0, and the output V can be forcedly outputted at this stage _O Pulled to 0, thereby reducing V _O The fall (trailing edge of the positive pulse) time of (a) the (a) pulse. On the other hand, at the beginning of the next cycle, the capacitor C needs to be charged forward, and the load resistor R _load The right-hand potential will drop to 0, if at this point the load resistance R _load If the left-side potential is still +VCC, then the load resistor R is charged in the forward direction of the capacitor C in the next period _load The voltage across it may create a jitter condition. The utility model uses the unique characteristics of the field bridge circuit to close the SW4 in the stage (6) so as to advance the load resistance R _load The left end potential is pulled to 0, so that the phenomenon of jitter generated in output at the stage can be effectively prevented.

Stage (7): SW1, SW4 and SW6 are closed, and SW2, SW3 and SW5 are open. At this time, the capacitor C is precharged in the forward direction by the dc high voltage power VCC, and a complete pulse period is ended and the next pulse is ready for output.

The above 7 phases together form a high voltage pulse period, each pulse period producing a negative pulse of-VCC and a positive pulse of +vcc. Based on the characteristics of the 'field' bridge circuit and simultaneously matched with the specific time sequence control of each group of power switches, the high-voltage fast switching circuit realizes the output effects of bipolar high-voltage pulse, stable load voltage, ultra-short pulse width, ultra-fast pulse rising edge and ultra-fast falling edge.

In addition, in the specific structural diagram of the power switch SW, the control signal P1 is generated by a micro-control processing unit, where the micro-control processing unit includes, but is not limited to, a programmable gate array (FPGA), a single chip microcomputer, a digital signal processing unit (DSP), a Central Processing Unit (CPU), a signal generator, and the like. The power transistors include, but are not limited to, metal Oxide Semiconductor Field Effect Transistors (MOSFETs), insulated Gate Bipolar Transistors (IGBTs), bipolar Junction Transistors (BJTs), junction Field Effect Transistors (JFETs), high Electron Mobility Transistors (HEMTs), and the like. The load resistor R _load Typical values are on the order of tens to hundreds of ohms. The current limiting resistor R _lim Typical values are on the order of a few ohms to tens of ohms. The capacitance C is typically on the order of several hundred nanofarads. The reverse diode connected in parallel with the power tube includes, but is not limited to, a zener diode, a Transient Voltage Suppression (TVS) diode, and the like. The large resistance in parallel with the power tube typically ranges from about a few mega ohms to several hundred mega ohms. In particular, the utility model is based on the innovative 'field' bridge circuit structure, can realize ultra-fast rising edge and falling edge and ultra-short pulse width, and the realization of the effect can be realized by common electronic components and chips without depending on high-end expensive electronic components and chips.

Fig. 6 is a bipolar high voltage pulse output waveform of the present utility model. In the figure, the OABC section constitutes a positive pulse portion of the high voltage output, and the DEFG section constitutes a negative pulse portion of the high voltage output. The longitudinal heights of the OA section and the BC section represent the amplitude of the high-voltage positive pulse, the transverse width of the OA section represents the rising time of the high-voltage positive pulse, the transverse width of the BC section represents the falling time of the high-voltage positive pulse, and the AB section represents the width of the positive pulse. Similarly, the vertical heights of the DE section and the FG section represent the amplitude of the high-voltage negative pulse, the lateral width of the DE section represents the rise time of the high-voltage negative pulse, the lateral width of the FG section represents the fall time of the high-voltage negative pulse, and the EF section represents the width of the negative pulse. In addition, the CD segment is the time difference between a positive pulse and a negative pulse, the GH segment is the time difference between a negative pulse and the next positive pulse, and OH is the period of a single positive and negative pulse. Based on the innovative 'field' bridge circuit structure, the utility model can generate high-voltage pulses with adjustable amplitude, rising time, falling time, frequency, pulse width, time difference between positive and negative pulses and pulse number by matching with the specific time sequence control of each group of power switches. In addition, bipolar pulse electric field ablation has better ablation effect and longer lasting ablation effect compared with unipolar pulse electric field ablation and radio frequency ablation.

Fig. 7 is an enlarged view of a portion of the positive pulse output waveform of the present utility model. In the figure, the OABC section forms a positive pulse part of high-voltage output, and the OA section and the BC section have certain transverse widths due to certain response delay in the opening and closing processes of the power switch. The lateral width of the OA segment represents the rise time of the high-voltage positive pulse, the lateral width of the BC segment represents the fall time of the high-voltage positive pulse, and the AB segment represents the width of the high-voltage positive pulse. In particular, based on the 'Tian Qiao' circuit structure, the high-voltage pulse width can be controlled within nanoseconds, and the rising time and the falling time of the high-voltage pulse can be controlled within picoseconds. Thus embodying the ultra-short pulse width and ultra-fast pulse rising and falling edges described in the present utility model.

The meaning of the fast pulse rising edge and falling edge is that the high voltage output has ultra-fast response, and the rising of the output voltage from zero to the target voltage and the falling from the target voltage to zero can be completed in extremely short time. The principle of myocardial tissue ablation by a pulsed electric field is that a membrane phospholipid bilayer moves and rearranges under the action of the pulsed electric field, so that irreversible electroporation is formed. The difficulty in forming the irreversible electroporation of the phospholipid bilayer is that the intensity of an applied electric field at the cell changes more quickly, namely the voltage applied to the two ends of the cell changes more quickly, the field intensity at the cell changes more quickly, and the phospholipid bilayer moves more quickly, so that the irreversible electroporation is formed more easily. Thus, the ultra-fast rising and falling edges of the high voltage pulses enable an ultra-fast variation of the field strength at the cells, which will make it easier for the membrane phospholipid bilayer to form irreversible electroporation. This also means that the voltage amplitude or pulse dose required for ultra-fast pulse rising and falling edges will be smaller than for slower pulse rising and falling edges if the same pulsed electric field ablation effect is to be achieved. The smaller voltage amplitude can reduce the probability of risk in the pulse electric field ablation process to a certain extent, and can reduce the design difficulty of a high-voltage pulse generation host and an ablation catheter; furthermore, a smaller pulse dose can reduce not only the time of the entire ablation procedure, but also the risk during the ablation procedure.

The pulse width of the existing high-voltage pulse generation host computer is more than microsecond, and the pulse energy of the level can generate certain heat in the ablation process, so that arterial blood vessels and nerve tissues around cardiac muscle can be damaged to a certain extent, and therefore postoperative complications are generated, and the safety in the operation process and the recovery effect of postoperative patients are affected. The 'field' bridge circuit can generate nanosecond ultra-short pulse width output, and hardly generates heat in an ablation process, so that the possible surgical risks are avoided.

In addition, because the energy generated by the nanosecond pulse width is extremely tiny, the influence of the energy on the heart rate of a human body is extremely tiny, so that the nanosecond pulse width and the high-voltage pulse of the nanosecond rising edge/falling edge can not depend on the electrocardiographic synchronization technology, and the safe ablation effect can be achieved.

Those skilled in the art will appreciate that all or part of the flow of the methods of the embodiments described above may be accomplished by way of a computer program to instruct associated hardware, where the program may be stored on a computer readable storage medium. Wherein the computer readable storage medium is a magnetic disk, an optical disk, a read-only memory or a random access memory, etc.

The present utility model is not limited to the above-mentioned embodiments, and any changes or substitutions that can be easily understood by those skilled in the art within the technical scope of the present utility model are intended to be included in the scope of the present utility model.

Claims (10)

1. A heart pulse electric field ablation system comprising a high voltage output module, the high voltage output module comprising:

a first branch comprising a first power switch and a second power switch connected in series;

a second branch including a fifth power switch and a sixth power switch connected in series;

an additional branch comprising a third power switch and a fourth power switch connected in series;

the first branch, the additional branch and the second branch are sequentially connected in parallel between a direct-current high-voltage power supply and a grounding end; and

a capacitor connected between a first node between the first power switch and the second power switch and a second node between the third power switch and the fourth power switch.

2. The heart pulse electric field ablation system of claim 1, further comprising:

The direct-current low-voltage power supply module is electrically connected with the direct-current high-voltage power supply module, the control device, the high-voltage output module and the input end of the touch screen in the ablation host;

the output end of the direct-current high-voltage power supply module is electrically connected with the high-voltage power supply input end of the high-voltage output module;

the control device is connected with each output end of the ablation host computer to detect each output parameter in real time and generate a control signal according to each output parameter;

the high-voltage output module is used for converting the direct-current high voltage into high-voltage pulses according to the control signals, and the high-voltage pulse output end of the high-voltage output module is electrically connected to ablation catheters of different models; and

and the touch screen is connected with the control device and displays various output parameters detected in real time in a data or graphic mode.

3. The system of claim 2, wherein the ablation catheter comprises a connection member, an ablation member, and an operative member interposed between the ablation member and the connection member, wherein,

the connection component comprises an electrical plug, a peripheral sheath and a luer connector,

the electric plug is used for electrically connecting the ablation catheter with the ablation host machine and conducting high-voltage pulse of the ablation host machine to an ablation electrode of the ablation unit;

The luer connector is used for being connected with an external device to realize air intake, air suction, physiological saline delivery, contrast agent delivery and superfluous blood discharge of the ablation catheter;

the ablation component comprises an ablation unit, a lead, an inner tube and an outer tube, wherein a plurality of ablation electrodes are fixed on the ablation unit and are used for applying the high-voltage pulse to pre-ablated tissue in the heart; and

the operating member includes a handle, an inner tube and an outer tube.

4. The system of claim 3, wherein the handle is provided with a bending mechanism and a telescoping deformation adjustment mechanism of the ablation unit, wherein,

the bending adjusting mechanism is used for adjusting the bending degree of the ablation part, so that the ablation part can realize adjustment of two degrees of freedom, and each degree of freedom can realize a bending angle of at least 60 degrees; and

the telescopic deformation adjusting mechanism is used for adjusting the contraction and the expansion of the ablation unit, wherein the ablation unit is in a contracted state when the ablation unit does not reach a pre-ablated tissue area yet; when the ablation unit has reached the pre-ablated tissue region, the ablation unit is in a deployed state while the ablation electrode at the ablation unit is deployed such that the ablation electrode is in contact with the pre-ablated tissue to apply the high voltage pulse to the pre-ablated tissue.

5. The heart pulse electric field ablation system of claim 1, further comprising:

a current limiting resistor connected between the capacitor and the second node; and

and a load resistor connected between the second node and a third node interposed between the fifth power switch and the sixth power switch.

6. The heart pulse electric field ablation system of claim 2, further comprising the first power switch to the sixth power switch for generating bipolar high voltage pulses according to the control signal, wherein the control device comprises a programmable gate array FPGA, a single chip microcomputer, a digital signal processing unit DSP, a central processing unit CPU, or a signal generator.

7. The heart pulse electric field ablation system of claim 6, wherein each of the first through sixth power switches comprises: the first isolation module, the second isolation module, the driving circuit and the power tube, wherein,

the output end of the first isolation module is connected to the input end of the driving circuit;

the output end of the second isolation module is connected with the power input end of the first isolation module through a direct current-direct current module; and

And the output end of the driving circuit is connected to the grid electrode of the power tube.

8. The heart pulse electric field ablation system of claim 7, wherein the first isolation module and the second isolation module each comprise an opto-electrical isolator, a magnetic isolator, or a transformer isolator.

9. The system of claim 7, wherein the power transistor comprises a MOSFET, an IGBT, a BJT, a JEET, and a HEMT.

10. The heart pulse electric field ablation system of claim 7, further comprising a reverse diode for connection in parallel with the power tube, wherein the reverse diode comprises a zener diode or a transient voltage suppression diode.

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