Impedance dynamic feedback-based pulsed field ablation system and use method thereof

Abstract

The invention provides a pulse field ablation system based on impedance dynamic feedback and a use method thereof, and the system comprises a pulse generator module which is used for generating a voltage pulse required by pulse field ablation; the ablation catheter module comprises a plurality of ablation electrodes and is used for transmitting the voltage pulses to the to-be-ablated heart tissue, and the activation modes of the ablation electrodes are determined according to the depth and range of the to-be-ablated heart tissue; the impedance detection module comprises an impedance sensor and is used for dynamically detecting electrical impedance in different ranges in the ablated heart tissue; the system control module is used for dynamically adjusting the voltage pulse generated by the pulse generator module, the activation modes of the plurality of ablation electrodes and the detection range of the impedance sensor according to different ranges of electrical impedance in the ablated heart tissue; and the visual interface interaction module is used for displaying the ablation process and serves as an operation interface of the ablation process. According to the invention, the assessment capability of the ablation effect can be improved, and the accuracy and success rate of the ablation process are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of electrophysiological instruments, and in particular, to a pulsed field ablation system based on impedance dynamic feedback and its usage method. Background Art

[0002] Arrhythmia diseases such as atrial fibrillation pose a significant threat to the health of patients. It not only increases the risk of stroke but may also lead to heart failure and other complications. In recent years, pulsed field ablation technology has gradually attracted attention due to its unique working principle and remarkable therapeutic effects. Compared with traditional radiofrequency ablation and cryoablation technologies, pulsed field ablation can effectively destroy diseased tissues in a shorter time and cause less damage to surrounding healthy tissues. However, current pulsed field ablation technologies lack an effective real-time feedback mechanism during the ablation process, making it difficult for physicians to evaluate the ablation effect in real time, and the depth of pulsed field ablation is insufficient, thus affecting the accuracy and safety of treatment.

[0003] During pulsed field ablation, myocardial cells generate nanoscale pores through the phenomenon of irreversible electroporation, resulting in changes in the structure of the cell membrane. The inventors of this patent found that this process is accompanied by a significant reduction in electrical impedance. If this impedance change can be monitored in real time and the activation position of the ablation electrode can be dynamically adjusted, not only can the ablation effect be effectively evaluated, but the ablation range and depth can also be adjusted accordingly. However, many existing pulsed field ablation systems currently do not fully utilize this characteristic and lack a design integrating impedance feedback, resulting in unsatisfactory treatment effects.

[0004] Research on existing pulsed field ablation technologies found that the patent with the application number CN202110731608.1 proposed a pulsed field ablation control method and system, which only adjusted the electrical pulse parameters based on the impedance characteristics of diseased tissues and could not specifically change the distribution position of the electric field intensity inside the tissue. As a result, the ablation range and depth effects could not be significantly improved. In addition, the patent with the application number 202411058947.8 proposed a pulsed field ablation method and system for the pulmonary vein vestibule, which monitored the voltage of the pulsed field ablation device in real time during pulsed field ablation and determined whether the voltage fluctuation of the pulsed field ablation device was abnormal within the target cycle. The purpose was to prevent surgical interruption and safety problems caused by abnormal system voltage fluctuations, but it did not optimize the ablation process and could not improve the ablation effect and success rate.

[0005] The patent with the authorization announcement number CN219147881U discloses a pulsed ablation system, which does not explain the functions of each module in the system, and the ablation catheter has a single structure, unable to adjust multiple ablation electrode modes, and does not realize dynamically adjusting ablation parameters according to tissue dynamic characteristics.

[0006] The patent with the application publication number CN118873240A discloses a device and method for real-time pulsed electric field ablation evaluation based on local impedance detection. The function of measuring local impedance is only to evaluate the ablation effect, and the ablation catheter module structure and mode disclosed are single, and the direction of the ablation electric field cannot be changed.

[0007] The limitations of these existing technologies indicate that there is an urgent need for a pulsed field ablation system that can integrate a real-time impedance feedback mechanism to improve the evaluation ability of ablation effect and increase the ablation depth. Summary of the Invention

[0008] Aiming at the defects in the prior art, the purpose of the present invention is to provide a pulsed field ablation system based on impedance dynamic feedback and its usage method.

[0009] According to one aspect of the present invention, there is provided a pulsed field ablation system based on impedance dynamic feedback, including:

[0010] A pulse generator module for generating voltage pulses required for pulsed field ablation;

[0011] An ablation catheter module including a plurality of ablation electrodes connected to the pulse generator module. The ablation electrodes are used to transfer the voltage pulses generated by the pulse generator module to the heart tissue to be ablated, so that the heart tissue undergoes irreversible electroporation. The activation modes of the plurality of ablation electrodes are determined according to the depth and range of the heart tissue to be ablated;

[0012] An impedance detection module including an impedance sensor for dynamically detecting the electrical impedance in different ranges of the ablated heart tissue;

[0013] A system control module is respectively connected to the pulse generator module, the ablation catheter module and the impedance detection module. The system control module dynamically adjusts the voltage pulses generated by the pulse generator module, the activation modes of the plurality of ablation electrodes and the detection range of the impedance sensor according to the electrical impedance in different ranges of the ablated heart tissue;

[0014] A visualization interface interaction module is connected to the system control module. The visualization interface interaction module is used to display the ablation process and serve as an operation interface for the ablation process.

[0015] Optionally, the plurality of ablation electrodes include a plurality of electrode parts with different shapes and / or sizes. After the plurality of electrode parts are activated, an electrode pair structure with multiple partitions is formed. The voltage pulses are transferred by activating any partition or a combined partition of the electrode pair structure to meet the ablation requirements for different depths and ranges.

[0016] Optionally, the impedance sensor has a plurality of electrode pairs, and the activation mode of the plurality of electrode pairs is determined according to the detected range of the impedance value of the ablated cardiac tissue.

[0017] Optionally, the voltage pulse generated by the pulse generator module includes any one of a unidirectional square wave pulse, a bidirectional square wave pulse, and an exponentially decaying pulse.

[0018] Optionally, for the unidirectional square wave pulse and the bidirectional square wave pulse, the adjustable range of the pulse voltage amplitude is 10V–10kV, the adjustable range of the number of pulses is 1–1000, the adjustable ranges of the pulse width and the pulse interval width are 10ns–100ms, and the adjustable range of the pulse repetition frequency is 0.1Hz–10MHz.

[0019] Optionally, for the exponentially decaying pulse, the adjustable range of the pulse voltage amplitude is 10V–10kV, the adjustable range of the number of pulses is 1–1000, the adjustable range of the pulse width is 10ns–100ms, the adjustable range of the pulse repetition frequency is 0.1Hz–10MHz, the adjustable range of the resistance is 10Ω–5000Ω, and the adjustable range of the capacitance is 10μF–5000μF.

[0020] Further, the system control module dynamically selects the number, position, and order of the activated ablation electrodes and the electrode pairs of the impedance sensor according to a preset target ablation mode and according to real-time feedback electrical impedance distribution data.

[0021] Further, the electric field intensity generated by the cooperation of the voltage pulse generated by the pulse generator module and the activated ablation electrodes exceeds the electric field intensity threshold at which myocardial cells undergo irreversible electroporation, satisfying E = U÷d > E threshold to ensure the optimization of the electric field distribution and the electric field intensity;

[0022] wherein, E is the electric field intensity generated by the cooperation of the voltage pulse and the activated ablation electrodes; U is the pulse voltage amplitude; d is the electrode spacing of the activated ablation electrodes; E threshold is the electric field intensity threshold at which myocardial cells undergo irreversible electroporation.

[0023] Optionally, the visualization interface interaction module includes a voltage pulse setting unit, a target ablation mode setting unit, an ablation electrode partition position distribution setting unit, and a dynamic electrical impedance distribution display unit.

[0024] According to another aspect of the present invention, there is provided a method for using the above-mentioned pulsed field ablation system based on impedance dynamic feedback, and the method includes:

[0025] Set the voltage pulse, target ablation mode, ablation electrode partition position distribution, and impedance sensor dynamic detection frequency in the visual interface interaction module;

[0026] According to the target ablation position and requirements of the heart tissue, implant the ablation catheter module into the target position and accurately position it;

[0027] Select and activate the first partition ablation electrode pair with the largest electrode spacing to transmit multiple groups of voltage pulses with specified parameters, and measure the impedance distribution of this part of the tissue once after each group of voltage pulses according to the target ablation mode; when the impedance difference measured after applying two adjacent groups of voltage pulses is less than the set value, this ablation operation is completed;

[0028] According to the impedance distribution result, select and activate the second partition ablation electrode pair with an electrode spacing one level smaller than that of the first partition ablation electrode pair, and repeat the same operation to complete the next ablation operation; and so on until the ablation steps required by the target ablation mode are completed;

[0029] After each ablation process, based on the impedance dynamic feedback result and the electric field strength distribution, adjust the voltage pulse parameters and the activated partition electrode pair strategy for the subsequent ablation steps, continuously increasing the ablation depth to ensure the accuracy and success rate of the continuous ablation process.

[0030] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0031] 1. Real-time impedance dynamic feedback: The system of the present invention integrates an impedance detection module, which can monitor the electrical impedance change of the ablated heart tissue in real time, thereby effectively evaluating the ablation effect and dynamically adjusting the ablation parameters according to the feedback information;

[0032] 2. Flexible pulse voltage configuration: Through the pulse generator module, the system of the present invention can generate various types of voltage pulses as required to adapt to different ablation requirements;

[0033] 3. Multi-electrode configuration and dynamic activation: The ablation catheter module is designed with multiple ablation electrodes, and the activation mode of the ablation electrodes is determined according to the depth and range of the heart tissue to be ablated, allowing flexible activation of any partition or combined partition electrodes to optimize the targeted ablation depth and range;

[0034] 4. Advanced ablation strategy: The system control module can dynamically select the most suitable electrodes and activation sequence according to the real-time impedance feedback and the preset ablation mode, further improving the accuracy of the ablation process;

[0035] 5. Visual monitoring and adjustment: The visual interface interaction module enables the operator to intuitively monitor the ablation process and adjust the program settings according to the real-time data, improving the flexibility and safety of the operation.

[0036] In summary, the pulsed field ablation system provided by the present invention can improve the ability to evaluate the ablation effect, ensure the accuracy and success rate of the ablation process, improve the effectiveness of treatment, enhance the real-time monitoring ability of the pulsed field ablation system, fill the gaps in the prior art, and provide a more effective solution for the treatment of arrhythmia. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Other features, objects, and advantages of the present invention will become more apparent by reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0038] Figure 1 It is a structural block diagram of a pulsed field ablation system based on impedance dynamic feedback in an embodiment of the present invention;

[0039] Figure 2 It is a flowchart of the usage method of a pulsed field ablation system based on impedance dynamic feedback in an embodiment of the present invention;

[0040] Figure 3 It is a schematic diagram of electrode settings and ablation results of pulsed field ablation process 1 based on impedance dynamic feedback in an embodiment of the present invention;

[0041] Figure 4 It is a schematic diagram of electrode settings and ablation results of pulsed field ablation process 2 based on impedance dynamic feedback in an embodiment of the present invention;

[0042] Figure 5 It is a schematic diagram of electrode settings and ablation results of pulsed field ablation process 3 based on impedance dynamic feedback in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those of ordinary skill in the art can make several modifications and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0044] Refer to Figure 1As shown in the figure, a pulsed field ablation system based on impedance dynamic feedback provided by an embodiment of the present invention includes a pulse generator module, an ablation catheter module, an impedance detection module, a system control module, and a visualization interface interaction module, where: The pulse generator module is used to generate voltage pulses required for pulsed field ablation; The ablation catheter module includes a plurality of ablation electrodes connected to the pulse generator module. The ablation electrodes are used to transfer the voltage pulses generated by the pulse generator module to the heart tissue to be ablated, so that irreversible electroporation occurs in this part of the heart tissue. The activation modes of the plurality of ablation electrodes, that is, the number and positions of the activated electrodes, are determined according to the depth and scope of the heart tissue to be ablated; The impedance detection module includes an impedance sensor. The impedance sensor is used to dynamically detect the electrical impedance in different ranges of the ablated heart tissue; The position of the impedance sensor is in the ablation catheter module. During operation, the impedance sensor contacts the heart tissue to dynamically detect the electrical impedance; The system control module is respectively connected to the pulse generator module, the ablation catheter module, and the impedance detection module. The system control module dynamically adjusts the voltage pulses generated by the pulse generator module, the activation modes of the plurality of ablation electrodes, and the detection range of the impedance sensor according to the electrical impedance in different ranges of the ablated heart tissue; The visualization interface interaction module is connected to the system control module. The visualization interface interaction module is used to display the ablation process and serve as an operation interface for the ablation process.

[0045] In some embodiments, the plurality of ablation electrodes include a plurality of electrode portions with different shapes and / or sizes. After the plurality of electrode portions are activated, an electrode pair structure with multiple partitions can be formed. When multiple electrode pairs are activated simultaneously, a combined partition electrode pair is formed. For the target ablation area of the heart tissue, a three-dimensional ablation scar will be formed after ablation. The distribution range of the ablation scar on the heart surface is called the ablation range, and the depth of the ablation scar in the heart is called the ablation depth. By activating the electrode pair structure of any partition or combined partition to transfer voltage pulses, that is, flexibly activating the electrode portions of the ablation catheter according to the partition, it can adapt to the ablation requirements of different depths and ranges.

[0046] The impedance detection module mainly includes an impedance sensor and an impedance detection circuit, and is used to dynamically detect the electrical impedance in different regions of the ablated heart tissue at different AC signal frequencies (that is, the dynamic detection frequency of the impedance sensor). In some embodiments, the impedance sensor has a plurality of electrode pairs. The activation modes of the plurality of electrode pairs are determined according to the detected range of the impedance value of the ablated heart tissue. The activation modes of the plurality of electrode pairs refer to the number and positions of the activated electrode pairs. By designing the impedance detection module to have a structure with a plurality of electrode pairs, the detection range can be flexibly selected.

[0047] The system in the embodiment of the present invention integrates an impedance detection module, can real-time monitor the change of the electrical impedance of the ablated heart tissue, realizes real-time impedance dynamic feedback, thereby effectively evaluating the ablation effect, and dynamically adjusting the ablation parameters according to the feedback information.

[0048] The pulse generator module mainly includes a power supply circuit, an energy storage element, and a pulse generation circuit, and is used to generate various types of voltage pulses required for pulsed field ablation. In some embodiments, the voltage pulses generated by the pulse generator module include any one of unidirectional square wave pulses, bidirectional square wave pulses, and exponentially decaying pulses, and have adjustable voltage amplitude, number of pulses, width, and frequency, etc.

[0049] Pulsed field ablation is a non-thermal ablation technique that mainly acts on cell membranes through high-voltage electrical pulses, resulting in irreversible penetrative damage to the cell membranes, thereby achieving the ablation effect. The pulsed voltage amplitude affects the electric field strength, which is the basis for the action of electroporation on tissues. The stronger the transmitted electric field, the greater the impact on the target tissue. However, as the electric field strength increases, the risk of generating heat also increases, leading to a transition to a thermal effect. Therefore, a higher output voltage means a higher field strength and possibly a larger damage range, but it also increases the risk of safety issues such as thermal effects, skeletal muscle contraction, microbubble formation, and even the occurrence of arcs. Increasing the number of pulses usually increases the overall observed effect. Some single-cell data suggest that when more than 16 pulses are applied, there is no significant difference in permeability or the death of 50% of the cell population. For the pulse width, an increase in the pulse duration will have a greater electroporation effect on cells; for longer pulses, a lower voltage is required to maintain the same number of electroporated cells. Especially when the duration is less than 1 millisecond, a higher voltage is required to achieve the same effect, but an excessive pulse duration increases the risk of thermal effects. The pulse interval width affects the pulse repetition frequency, that is, the time interval between pulses, and electroporation depends on the pulse repetition rate. The pulse repetition frequency refers to the number of times the pulse repeats per unit time. Increasing the pulse repetition frequency usually increases the overall observed effect.

[0050] The above parameters jointly determine the effect of pulsed field ablation. There are complex interactions among the parameters, and the specific value of each parameter depends on the specific ablation target and tissue characteristics.

[0051] In some embodiments, for unidirectional square wave pulses and bidirectional square wave pulses, the adjustable range of the pulsed voltage amplitude is 10V - 10kV, the adjustable range of the number of pulses is 1 - 1000, the adjustable ranges of the pulse width and the pulse interval width are 10ns - 100ms, and the adjustable range of the pulse repetition frequency is 0.1Hz - 10MHz.

[0052] In some embodiments, for exponentially decaying pulses, the adjustable range of the pulse voltage amplitude is 10 V–10 kV, the adjustable range of the number of pulses is 1–1000, the adjustable range of the pulse width is 10 ns–100 ms, the adjustable range of the pulse repetition frequency is 0.1 Hz–10 MHz, the adjustable range of the resistance is 10 Ω–5000 Ω, and the adjustable range of the capacitance is 10 μF–5000 μF.

[0053] Exemplarily, the voltage pulse generated by the pulse generator module is a unidirectional square wave pulse, where multiple pulse parameters are independent and arbitrarily adjustable. The pulse voltage amplitude is 300 V, the number of pulses is 100, the pulse width is 100 μs, and the pulse repetition frequency is 1 Hz.

[0054] Through the pulse generator module, the system in the embodiments of the present invention can generate various types of voltage pulses as required. The system has a flexible pulse voltage configuration and can adapt to different ablation requirements.

[0055] In the above embodiments of the present invention, the system control module dynamically selects the ablation electrode and activation sequence that are most suitable for the partition according to the preset target ablation mode and the real-time feedback electrical impedance distribution data, that is, the activation quantity, position, and sequence of the activated ablation electrode and the electrode pair of the impedance sensor. The preset target ablation modes include a transmural injury mode (causing penetrating injury to the heart), a deep injury mode (causing injury from one side surface to deep tissue of the heart but not transmural), a superficial injury mode (causing injury to the superficial layer on one side of the heart), etc. According to the characteristics of different regions in the ablated heart tissue (including electrical impedance distribution and ablation electrode position) feedback during implementation, ablation parameters such as voltage pulses, impedance sensors, and activation modes of ablation electrodes are controlled and dynamically adjusted to further improve the accuracy of the ablation process.

[0056] In the above embodiments of the present invention, the electric field strength generated by the cooperation of the voltage pulse generated by the pulse generator module and the activated ablation electrode exceeds the electric field strength threshold for myocardial cells to undergo irreversible electroporation, that is, it satisfies: E = U÷d > E threshold to ensure the optimization of the electric field distribution and electric field strength;

[0057] wherein, E is the electric field strength generated by the cooperation of the voltage pulse and the activated ablation electrode; U is the pulse voltage amplitude; d is the electrode spacing of the activated ablation electrode; E threshold is the electric field strength threshold for myocardial cells to undergo irreversible electroporation, and the common value is 400 V / cm.

[0058] In some embodiments, the visual interface interaction module includes a voltage pulse setting unit, a target ablation mode setting unit, an ablation electrode partition position distribution setting unit, and a dynamic electrical impedance distribution display unit. The visual interface interaction module provides the operator with real-time monitoring and adjustment functions. With the aid of the visual interface interaction module, the system operator can intuitively monitor the ablation process and adjust the parameters during the ablation process according to the ablation process, improving the flexibility and safety of the operation.

[0059] In the system of the above embodiments of the present invention, the ablation electrodes in the ablation catheter module include multiple electrode pair parts, which are divided into structures such as 3 partition electrode pairs and are distributed in different ranges of the heart tissue to be ablated. Any partition of the ablation electrode pairs can be flexibly activated to transmit voltage pulses to meet the ablation requirements of different depths and ranges. The impedance sensor in the impedance detection module has a structure with multiple electrode pairs and can be flexibly selected to detect the tissue impedance values in different ranges and feedback them to the system control module. The ablation catheter module and the impedance detection module are in contact with the heart tissue to realize the transmission of electrical pulses and the detection of electrical impedance. The system control module generates system control signals for the impedance detection module and the like. In the embodiments of the present invention, the electrical impedance of different regions in the heart tissue to be ablated is dynamically detected by the impedance sensor in the impedance detection module, so that the system control module can control and dynamically adjust the voltage pulses, the activation mode of multiple partition ablation electrodes, and the ablation electrical pulse parameters according to the impedance characteristics of different regions in the heart tissue to be ablated. The visual interface interaction module can also facilitate the system operator to intuitively monitor the ablation process and adjust the program settings according to the ablation process. By integrating multiple types of voltage pulses and a real-time impedance monitoring mechanism, and the cooperation between each module, the ablation effect can be dynamically evaluated, the treatment parameters and the activated ablation electrode configuration can be optimized, the evaluation ability of the ablation effect can be improved, the accuracy and ablation depth of the ablation process can be significantly enhanced, the effectiveness of the treatment can be improved, and the real-time monitoring ability of the pulsed field ablation system can also be enhanced. The system in the above embodiments of the present invention provides a more effective solution for the treatment of arrhythmia.

[0060] Referring to Figure 2 As shown, another embodiment of the present invention provides a method for using the above pulsed field ablation system based on impedance dynamic feedback, and the method includes:

[0061] S1. Before using the system, perform some pre-setting operations. Set the voltage pulse (including the type and parameters of the voltage pulse), the target ablation mode (such as transmural injury), the position distribution of the ablation electrode partitions, and the dynamic detection frequency of the impedance sensor (for example, 1000 Hz) in the visual interface interaction module; different detection frequencies will cause changes in the impedance values of the equivalent inductance and capacitance in the detected tissue. The impedance of the inductance increases with the increase in frequency, while the impedance of the capacitance decreases with the increase in frequency. That is, at different detection frequencies, the impedance will also be different;

[0062] S2. According to the target ablation position and requirements of the cardiac tissue, implant the ablation catheter module into the target position in the atrium and accurately position it;

[0063] S3. Select and activate the first partition ablation electrode pair with the largest electrode spacing to transmit multiple sets of voltage pulses with specified parameters, and measure the impedance distribution of this part of the tissue once after each set of voltage pulses according to the target ablation mode; according to the impedance distribution result of this part of the tissue, when the impedance difference measured after applying two adjacent sets of voltage pulses is less than the set value, this ablation operation is completed;

[0064] S4. According to the impedance distribution result, select and activate the second partition ablation electrode pair with an electrode spacing one level smaller than that of the first partition ablation electrode pair in step S3, and repeat the same operation to complete the next ablation operation; and so on until the ablation steps required by the target ablation mode are completed;

[0065] S5. The voltage pulse is transmitted to the cardiac tissue through the ablation electrode, generating an electric field intensity and distribution of specific magnitude and position on the tissue. For the same ablation electrode, changing the voltage magnitude of the electric pulse can generate different electric field intensity distributions; and for the same electric pulse parameters, changing the number and / or position of the ablation electrode pairs can generate different electric field intensity distributions of different magnitudes and directions. After each ablation process, based on the impedance dynamic feedback result and the electric field intensity distribution (cooperated by the voltage pulse generated by the pulse generator module and the activated ablation electrode), adjust the voltage pulse parameters and the activated partition electrode pair strategy for the subsequent ablation steps, continuously increasing the ablation depth to ensure the accuracy and success rate of the continuous ablation process.

[0066] For the above steps S3 and S4, further description will be given below with reference to the accompanying drawings.

[0067] For ablation electrodes including multiple different shapes and sizes, the embodiments of the present invention enable electrodes in different partitions layer by layer, which can activate electrode pairs with different spacings and positions, thereby achieving ablation results of different sizes and positions.

[0068] First, activate as Figure 3The electrode pair shown (electrode setting 1), that is, the two outermost electrodes are enabled respectively (ablation process 1), and the scar range obtained after ablation is larger but the depth is smaller (ablation result 1). After impedance sensor detection, the tissue impedance of ablation region 1 in ablation result 1 decreases, which is beneficial to current transmission, and this impedance dynamic result is fed back to the system control module.

[0069] Further, activate the electrode pair shown as Figure 4 (electrode setting 2), that is, the two electrodes with the spacing reduced by one level are activated respectively (ablation process 2). Since the tissue conductivity in ablation result 1 generated in the first step decreases and the activated electrode pair range shrinks, the scar range obtained after ablation shrinks but the depth increases significantly (ablation result 2). After impedance sensor detection, the tissue impedance of ablation region 2 in ablation result 2 further decreases, which is beneficial to current transmission, and this impedance dynamic result is fed back to the system control module.

[0070] Finally, activate the electrode pair shown as Figure 5 (electrode setting 3), that is, the two innermost electrodes are enabled respectively (ablation process 3). Since the tissue conductivity in the ablation scars generated in the previous two steps decreases and the activated electrode pair range further shrinks, the final scar range further shrinks and transmural injury of cardiac tissue is achieved (ablation result 3).

[0071] Thus, through impedance dynamic feedback and layer-by-layer activation of ablation electrodes, transmural pulsed field ablation of cardiac tissue can be achieved.

[0072] The usage method of the above system of the present invention includes setting ablation parameters, accurately positioning the ablation catheter, applying voltage pulses and performing impedance detection, and dynamically adjusting subsequent operations according to the feedback results to ensure the accuracy and success rate of the ablation process. The embodiments of the present invention provide a new and efficient ablation technique for the treatment of heart diseases.

[0073] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various deformations or modifications within the scope of the claims, which do not affect the essence of the present invention. The above preferred features can be combined arbitrarily without conflict.

Claims

1. A pulsed field ablation system based on impedance dynamic feedback, characterized in that: include: A pulse generator module, used for generating voltage pulses required for pulse field ablation; an ablation catheter module, comprising a plurality of ablation electrodes connected to the pulse generator module, the ablation electrodes being used to transmit the voltage pulses generated by the pulse generator module to the cardiac tissue to be ablated, so that irreversible electroporation occurs in the cardiac tissue, and the activation mode of the plurality of ablation electrodes is determined according to the depth and range of the cardiac tissue to be ablated; An impedance detection module, comprising an impedance sensor, wherein the impedance sensor is used to dynamically detect electrical impedances of different ranges in the ablated cardiac tissue; A system control module, connected to the pulse generator module, the ablation catheter module and the impedance detection module respectively, and the system control module dynamically adjusts the voltage pulses generated by the pulse generator module, the activation mode of multiple ablation electrodes and the detection range of the impedance sensor according to different ranges of electrical impedance in the ablated cardiac tissue; A visualization interface interaction module is connected to the system control module, and is used to display the ablation process and serve as an operation interface of the ablation process.

2. The pulsed field ablation system based on impedance dynamic feedback according to claim 1, characterized in that: The multiple ablation electrodes include multiple electrode parts of different shapes and / or sizes. After being activated, the multiple electrode parts form multiple partitioned electrode pair structures. Voltage pulses are transmitted by activating the electrode pair structure of any partition or combined partitions to adapt to ablation requirements of different depths and ranges.

3. The pulsed field ablation system based on impedance dynamic feedback according to claim 1, characterized in that: The impedance sensor has a plurality of electrode pairs, and activation patterns of the plurality of electrode pairs are determined according to a detection range of impedance values ​​of the ablated cardiac tissue.

4. The pulsed field ablation system based on impedance dynamic feedback according to claim 1, characterized in that: The voltage pulse generated by the pulse generator module includes any one of a unidirectional square wave pulse, a bidirectional square wave pulse and an exponential decay pulse.

5. The pulsed field ablation system based on impedance dynamic feedback according to claim 4, characterized in that: For the unidirectional square wave pulse and the bidirectional square wave pulse, the adjustable range of the pulse voltage amplitude is 10V-10kV, the adjustable range of the number of pulses is 1-1000, the adjustable range of the pulse width and the pulse interval width is 10ns-100ms, and the adjustable range of the pulse repetition frequency is 0.1Hz-10MHz.

6. The pulsed field ablation system based on impedance dynamic feedback according to claim 4, characterized in that: For the exponential decay pulse, the adjustable range of the pulse voltage amplitude is 10V–10kV, the adjustable range of the pulse number is 1–1000, the adjustable range of the pulse width is 10ns–100ms, the adjustable range of the pulse repetition frequency is 0.1Hz–10MHz, the adjustable range of the resistance is 10Ω–5000Ω, and the adjustable range of the capacitance is 10μF–5000μF.

7. The pulsed field ablation system based on impedance dynamic feedback according to claim 1, characterized in that: The system control module dynamically selects the number, position and sequence of electrode pairs of activated ablation electrodes and impedance sensors according to a preset target ablation mode and real-time feedback electrical impedance distribution data.

8. The pulsed field ablation system based on impedance dynamic feedback according to claim 1, characterized in that: The electric field strength generated by the voltage pulse generated by the pulse generator module and the activated ablation electrode exceeds the electric field strength threshold for irreversible electroporation of myocardial cells, satisfying E=U÷d>E threshold , to ensure the optimization of electric field distribution and electric field strength; Wherein, E is the electric field strength generated by the voltage pulse and the activated ablation electrode; U is the pulse voltage amplitude; d is the electrode spacing of the activated ablation electrode; E threshold The electric field intensity threshold for irreversible electroporation of cardiomyocytes.

9. The pulsed field ablation system based on impedance dynamic feedback according to claim 1, characterized in that: The visualization interface interaction module includes a voltage pulse setting unit, a target ablation mode setting unit, an ablation electrode partition position distribution setting unit and a dynamic electrical impedance distribution display unit.

10. A method for using the pulsed field ablation system based on impedance dynamic feedback according to any one of claims 1 to 9, characterized in that: include: Set the voltage pulse, target ablation mode, ablation electrode partition position distribution and impedance sensor dynamic detection frequency in the visual interface interaction module; According to the target ablation position and requirements of cardiac tissue, the ablation catheter module is implanted into the target position and precisely positioned; The first subarea ablation electrode pair with the largest electrode spacing is selected and activated to transmit multiple groups of voltage pulses with specified parameters, and the impedance distribution of the part of the tissue is measured once after each group of voltage pulses according to the target ablation mode; when the impedance difference measured after applying two adjacent groups of voltage pulses is less than the set value, this step of the ablation operation is completed; According to the impedance distribution result, a second partition ablation electrode pair with an electrode spacing one level smaller than that of the first partition ablation electrode pair is selected and activated, and the same operation is repeated to complete the next ablation operation; and so on, until the ablation step required by the target ablation mode is completed; After each ablation step, the voltage pulse parameters of the subsequent ablation steps and the strategy of activated partitioned electrode pairs are adjusted based on the impedance dynamic feedback results and the electric field strength distribution, and the ablation depth is continuously increased to ensure the accuracy and success rate of the continuous ablation process.

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