Electrodes, methods of making and methods of using for cardiac tissue pulsed field ablation

Abstract

The application provides an electrode for cardiac tissue pulse field ablation, a preparation method and a use method, the electrode has a multi-stage partition structure, each partition contains at least a pair of independently activated electrode pairs, the cathode and the anode of the electrode pair are arranged alternately, the distance between the anode and the cathode in the electrode pair gradually decreases from outside to inside, by activating different electrode pairs, the direction and intensity of the electric field are adjusted to adapt to the ablation requirements of different depths and ranges of cardiac tissue. The application also provides a preparation method and a use method of the electrode. The application can accurately control the distribution and intensity of the pulse field, realize deep tissue penetration at a lower voltage, and thus improve the effectiveness and safety of cardiac disease treatment.

Description

Technical Field

[0001] This invention relates to the field of microelectrode technology, specifically to an electrode for pulsed field ablation of cardiac tissue, its preparation method, and its usage method. Background Technology

[0002] Atrial fibrillation (AF) is the most common sustained arrhythmia in clinical practice, affecting as many as 59.7 million people, and its incidence is rapidly increasing with the aging population. Minimally invasive catheter ablation uses a thin catheter, approximately 3 mm in diameter, delivered to the heart via the femoral vein or artery. By manipulating the catheter, abnormal lesions in the cardiac tissue are ablated, thus treating the arrhythmia. In recent years, cardiac pulse field ablation has gained widespread attention in the medical and scientific communities due to its tissue-specific selectivity and lack of thermal sink effects, resulting in fewer postoperative complications such as stroke, phrenic nerve paralysis, pulmonary vein stenosis, coronary artery stenosis, and atrial-esophageal fistula.

[0003] Existing treatment techniques are often limited by electrode design and the precision of electric field control. Traditional cardiac ablation techniques often use electrodes that cannot precisely control the distribution and intensity of the electric field, which may lead to unnecessary damage to surrounding healthy tissue during ablation or failure to effectively achieve the desired treatment depth. Furthermore, electrodes in existing technologies typically require high voltages to achieve sufficient tissue penetration, increasing the risk and complexity of the procedure.

[0004] A search revealed Chinese invention patent application CN115568938A, which discloses a fractal structure microelectrode, its fabrication method, and a conduit. The microelectrode includes: a substrate layer with pads; a conductive layer above the substrate layer, including electrode points electrically connected to the pads; each electrode point comprising a central anode and an outer cathode, with interdigitated structures of the anode and cathode; an encapsulation layer above the conductive layer, exposing the electrode points and pads; and an electrode modification layer formed on the electrode points. An electrical pulse is applied to cardiac tissue through the anode and cathode, causing irreversible electroporation ablation of cardiac cells. However, this electrode, once activated, generates a single electric field, allowing only a single-stage ablation of the pulsed field, making it difficult to achieve high-precision, deep ablation of the heart. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide an electrode, its preparation method, and its usage method for pulsed field ablation of cardiac tissue.

[0006] According to a first aspect of the present invention, an electrode for pulsed field ablation of cardiac tissue is provided, the electrode having a multi-level partitioned structure, each partition containing at least one pair of independently activatable electrodes, the cathodes and anodes of the electrode pairs being arranged crosswise, the distance between the anode and cathode in the electrode pairs gradually decreasing from the outside to the inside, and by activating different electrode pairs, the direction and intensity of the electric field are adjusted to adapt to the ablation requirements of different depths and ranges of cardiac tissue.

[0007] Furthermore, in the multi-level partition structure, the number of partitions is determined according to the distance between the anode position and the electrode center. The partition where the anode is closest to the electrode center is the primary structure, and the distance between the anode and the cathode is the largest in the electrode pair of the primary structure.

[0008] Furthermore, the anode of the primary structure is located at the center of the electrode, and the anodes of the multi-level partitioned structure are arranged sequentially from the center of the electrode in order of increasing level. The anodes of different levels are arranged to cross each other. The cathode of the multi-level partitioned structure is located on the outer ring of the electrode, and the cathodes of different levels are arranged at intervals.

[0009] Furthermore, the shape and arrangement of the electrode pairs in each partition are determined according to the electric field distribution pattern.

[0010] Furthermore, the electrode comprises, from bottom to top, a lower insulating layer, an electrode layer, an upper insulating layer, and an electrode modification layer. The electrode layer is used to apply pulsed electrical signals to the heart tissue and simultaneously record the electrical impedance of the heart tissue before and after each pulsed field ablation.

[0011] Furthermore, the electrode has at least one of the following characteristics:

[0012] The electrode layer is made of any one of gold, platinum, copper, graphene, and liquid alloys.

[0013] The material of the electrode modification layer is selected from any one of platinum black, iridium oxide, MXenes and polyvinyl dioxythiophene-polystyrene sulfonic acid;

[0014] The materials of the substrate layer and the encapsulation layer are selected from any one of polyimide, parylene, SU-8 photoresist and silk protein.

[0015] According to a second aspect of the present invention, a method for preparing an electrode for pulsed field ablation of cardiac tissue, as described in the first aspect, is provided, the method comprising:

[0016] Fabricate a substrate layer on a substrate material;

[0017] An adhesive layer is fabricated on the base layer, then a conductive layer is fabricated, and finally the conductive layer is patterned.

[0018] An encapsulation layer is fabricated on the conductive layer;

[0019] Spin-coat photoresist, pattern the photoresist using photolithography, and use dry etching to etch and expose the electrode points, pads, and overall outline of the electrode devices.

[0020] The electrode device is released, and an electrode modification layer is fabricated on the electrode point to obtain an electrode for pulsed field ablation of cardiac tissue.

[0021] According to a third aspect of the present invention, a method of using an electrode of the first aspect or an electrode prepared by the method of the second aspect is provided, the method of use comprising:

[0022] Based on the direction and intensity of the electric field required for cardiac tissue ablation, activate electrode pairs in multi-level zones;

[0023] During each ablation step, the electrical pulse parameters and electrode pair activation sequence are adjusted according to the changes in the electrical impedance of the heart tissue. The distribution and intensity of the electric field are also adjusted to achieve ablation of different sizes and locations within the heart tissue, so as to precisely control the ablation depth and range.

[0024] Furthermore, during the ablation process, an equivalent circuit model was used to assess the changes in the electrical impedance of cardiac tissue during the ablation process.

[0025] Furthermore, after each ablation step, the electrical pulse parameters and electrode pair activation sequence of subsequent ablation steps are adjusted based on feedback data of cardiac tissue electrical impedance and electric field intensity.

[0026] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0027] This invention employs a multi-level partitioned electrode pair design, where each partition's electrode pair can be activated independently. By activating different configurations of electrode pairs, the direction and intensity of the electric field can be controlled. Through its unique partitioned electrode design and layer-by-layer activation, this invention enables precise control of the pulse field distribution and intensity. By adjusting layer-by-layer activation, it achieves deep tissue penetration at lower voltages while minimizing damage to surrounding healthy tissues, thereby significantly improving the effectiveness and safety of cardiac disease treatment. Attached Figure Description

[0028] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0029] Figure 1 This is a schematic diagram of the partitioned electrode structure in one embodiment of the present invention;

[0030] Figure 2This is a schematic diagram of the partitioned electrode array in one embodiment of the present invention;

[0031] Figure 3 This is a method for preparing electrodes in one embodiment of the present invention;

[0032] Figure 4 This is an embodiment of the present invention, showing the electrode-tissue equivalent circuit model and a simplified model before and after ablation.

[0033] Figure 5 This is a schematic diagram of the layer-by-layer activation of the partitioned structure electrodes in one embodiment of the present invention;

[0034] Figure 6 This is a schematic diagram of the layer-by-layer activation of the partitioned electrode array in one embodiment of the present invention;

[0035] Figure 7 This is a schematic diagram illustrating the ablation effect of the partitioned electrode layer-by-layer ablation strategy in one embodiment of the present invention. Detailed Implementation

[0036] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0037] The accompanying drawings illustrate various structural schematics according to embodiments of this application. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions according to actual needs, all of which fall within the scope of protection of this invention.

[0038] This invention provides an electrode for pulsed field ablation of cardiac tissue, as described in the following embodiment. Figure 1 and Figure 2 The electrode has a multi-level partitioned structure, with each partition containing at least one pair of independently activatable electrodes. The cathodes and anodes of the electrode pairs are arranged in an alternating manner, and the distance between the anode and cathode in the electrode pair gradually decreases from the outside to the inside. By activating different electrode pairs, such as electrode pairs located in different partitions or electrode pairs in the same partition, an electric field with adjustable direction and intensity is generated, thereby adjusting the direction and intensity of the electric field to meet the ablation needs of different depths and ranges of cardiac tissue.

[0039] The electrodes in this embodiment of the invention adopt a partitioned design, wherein each partition contains at least one pair of independently activatable electrodes. The arrangement of cathodes and anodes in the multi-level partitions follows the principle of convergence from the outside to the inside, that is, the distance between the anode and cathode in the electrode pair gradually decreases, thereby increasing the depth of the generated electric field and realizing deep ablation of heart tissue. This allows the electrodes to be activated layer by layer from the center of the electrode, thereby achieving precise control of the distribution and intensity of the pulse field.

[0040] In a multi-level partitioned structure, the number of partitions is determined by the distance between the anode position and the electrode center. The partition where the anode is closest to the electrode center is the primary structure. The distance between the anode and cathode in the electrode pair varies within each level of partition. The primary structure has the largest distance between the anode and cathode in the electrode pair, while higher-level partitions have closer electrode pairs. Each partition contains at least one pair of electrodes to accommodate different depths and ranges of cardiac tissue ablation. In some embodiments, the anode of the primary structure is located at the center of the electrode. The anodes of the multi-level partitioned structure are arranged sequentially from the center of the electrode in ascending order of their level, with anodes of different levels interleaved.

[0041] In some implementations, the cathode with a multi-level partitioned structure is located on the outer ring of the electrode, and cathodes with different levels of structure are spaced apart.

[0042] The partitioned design structure of the microelectrodes in the above embodiments of the present invention includes, but is not limited to, primary structures, secondary structures, tertiary structures, and higher-level structures. The primary structure refers to an electrode pair consisting of a central anode and an outermost cathode; the secondary structure is an electrode pair consisting of an inner anode and an outer anode. Similarly, higher-level partitioned structures consist of inner and outer electrode pairs with different positions. This allows for precise control of the electric field strength and distribution to meet the ablation needs of cardiac tissue at different depths and ranges.

[0043] In some implementations, the shape and arrangement of the electrode pairs in each partition are determined according to the electric field distribution pattern. For example, the electrode pairs in each partition can be arranged linearly, in a mesh pattern, or arbitrarily to support different types of electric field distribution patterns.

[0044] In some embodiments, the electrode comprises, from bottom to top, a lower insulating layer, an electrode layer, an upper insulating layer, and an electrode modification layer. The electrode layer is used to apply pulsed electrical signals to the heart tissue and simultaneously record the electrical impedance of the heart tissue before and after each pulsed ablation.

[0045] In some embodiments, the electrode layer is made of a conductive material selected from gold, platinum, copper, graphene, and liquid alloys. These materials can withstand high voltages of several hundred volts, providing stable and efficient electron transport, thereby enabling the application of pulsed electrical signals to cardiac tissue while simultaneously recording the electrical impedance of the cardiac tissue before and after each pulsed ablation.

[0046] In some embodiments, the material of the electrode modification layer is selected from any one of platinum black, iridium oxide, MXenes, and polyvinyl dioxythiophene-polystyrene sulfonic acid. These materials possess excellent electrochemical properties, biocompatibility, and stable redox properties, providing efficient electron transport and good mechanical flexibility, thereby enhancing the conductivity and mechanical properties of the electrode.

[0047] The substrate and encapsulation layers are made of insulating materials. In some embodiments, the substrate material is selected from any one of polyimide, parylene, SU-8 photoresist, and silk fibroin. Similarly, the encapsulation layer material is selected from any one of polyimide, parylene, SU-8 photoresist, and silk fibroin. These materials possess excellent insulating properties, chemical inertness, and biocompatibility, providing effective moisture protection, corrosion protection, and electrical insulation protection, enabling the electrodes to be suitable for various environmental conditions.

[0048] It should be noted that in some other embodiments, the lower insulating layer, electrode layer, upper insulating layer and electrode modification layer may be made of other materials, as long as they can achieve the same function as described above.

[0049] In addition to electrodes with layered activation structures, electrode arrays can be formed using multiple electrodes from the above embodiments, allowing multiple electrodes to work independently or collaboratively. For example, this can be achieved through... Figure 2 The simplest point-like electrodes shown form an electrode array, enabling step-by-step, layer-by-layer activation.

[0050] Based on the same inventive concept, another embodiment of the present invention provides a method for preparing the above-mentioned electrode for pulsed field ablation of cardiac tissue, referring to... Figure 3 The method includes:

[0051] S1. Fabricate a substrate layer on a substrate material such as a silicon wafer;

[0052] S2. An adhesive layer is made on the base layer, then a conductive layer is made, and then the conductive layer is patterned to form a conductive layer with a specific shape.

[0053] S3. Fabricate an encapsulation layer on the conductive layer;

[0054] S4. Spin-coating photoresist, patterning the photoresist through photolithography, and using dry etching to etch and expose the electrode point part, the pad part and the overall outline of the electrode device.

[0055] S5. Release the electrode device and fabricate an electrode modification layer on the electrode point to obtain an electrode for pulsed field ablation of cardiac tissue.

[0056] In the embodiments of the preparation method of the present invention, the materials used for each layer of the electrode structure refer to the corresponding technical features in the electrode embodiments described above, and will not be described in detail here.

[0057] The embodiments of the present invention utilize micro-nano fabrication technology to prepare hierarchical electrodes or electrode arrays with partitions, enabling layered activation. This high-precision manufacturing technology allows for the precise configuration of electrode structures to meet specific medical needs. The multi-layered structure of the electrode device not only enables the application of pulsed electrical signals for ablation but also records the electrical impedance of cardiac tissue before and after ablation, providing the possibility of immediate feedback on treatment effects. This is of great value for achieving personalized and precision treatment.

[0058] Based on the same inventive concept, another embodiment of the present invention also provides a method for using the above-mentioned electrode, comprising: activating electrode pairs in multi-level partitions according to the direction and intensity of the electric field required for ablation of cardiac tissue; adjusting the electrical pulse parameters and the activation sequence of the electrode pairs according to the changes in the electrical impedance of cardiac tissue during each ablation step, adjusting the distribution and intensity of the electric field, so as to achieve ablation of different sizes and locations within cardiac tissue, thereby precisely controlling the ablation depth and range.

[0059] In some implementations, during the ablation process, an equivalent circuit model is used to assess the changes in the electrical impedance of cardiac tissue during ablation, thereby adjusting the electrode pair configuration in real time to ensure the optimization of electric field distribution and intensity.

[0060] Reference Figure 4 The electrode-tissue equivalent circuit model and simplified models before and after ablation are shown, illustrating the study of the electrode-tissue equivalent circuit model and impedance changes. To further investigate the tissue electrical properties during ablation, an electrode-tissue equivalent circuit model was constructed to optimize subsequent ablation protocols. The complete circuit model for a single cell is shown below. Figure 4 As shown in Figure a, the physical meaning of each part is as follows: Figure 4As shown in b. Cells are mainly composed of a cell membrane, cytoplasm, organelles, and nucleus, with the cell membrane exhibiting high electrical resistance. Under normal circumstances, the cell membrane is typically considered a dielectric, equivalent to a capacitor. However, actual cell membranes and specific ion channels on the membrane have some defects, thus current pathways still exist. Theoretically, the cell membrane is equivalent to a capacitor and a resistor connected in parallel. Similarly, organelle membranes and the nuclear membrane can also employ the same equivalent circuit as the cell membrane. Due to the high ion concentrations in intracellular and extracellular fluids, they are simplified to resistors. The cell membrane resistance is on the order of megaohms at low frequencies, therefore the cell membrane primarily exhibits capacitive characteristics. The cytoplasmic resistance is relatively small, typically hundreds or thousands of ohms. Biological tissues are composed of cells, therefore the equivalent circuit of biological tissues can be composed of the cell equivalent circuit. To simplify the model, considering the symmetry of cell structures, a simplified model (e.g., ...) is used in applications. Figure 4 c). For electrodes within tissue, the liquid resistance, electrode polarization resistance, and electrode surface capacitance are represented by RL, Rep, and Csc, respectively. Under normal circumstances, due to the relatively high cell membrane resistance Rc, most of the current flows through Rs. During pulsed field ablation, irreversible electroporation occurs, creating nanoscale pores on the cell membrane, leading to inward flow of ions (such as Ca2+, K+, and Na+). This is equivalent to generating parallel resistances Rci (such as...) on the cell membrane. Figure 4 d). Therefore, an important result of pulsed field ablation is the reduction of tissue electrical impedance.

[0061] In some implementations, after each ablation step, the electrical pulse parameters and electrode pair activation sequence of subsequent ablation steps are adjusted based on feedback data of cardiac tissue electrical impedance and electric field intensity to ensure the accuracy and efficiency of the continuous ablation process.

[0062] This invention utilizes impedance and electric field strength feedback to activate electrode pairs with different configurations layer by layer, thereby achieving ablation points of different sizes and locations within the heart tissue. This invention also utilizes the principle of changes in the conductivity of heart tissue to precisely control the ablation depth and range, in order to achieve the target therapeutic effect.

[0063] Compared to existing technologies, the electrodes in the above embodiments of the present invention, due to their multi-level partitioned structure, can select different electrode activation strategies to generate diverse electric fields. During the ablation process, by switching different electrode strategies, the electric fields are superimposed on the same cardiac tissue region, thereby achieving high-precision and deep ablation of the heart.

[0064] The embodiments of this invention primarily target the treatment of complex cardiac diseases such as atrial fibrillation, offering novel solutions, particularly addressing the precision and safety requirements that traditional ablation techniques struggle to achieve. These embodiments focus on innovative treatment methods for cardiac diseases through highly refined electrode design and real-time feedback mechanisms. By comprehensively applying micro-nano fabrication technology, zoned and layer-by-layer activatable electrode design, real-time monitoring, and dynamic adjustment strategies, the ablation process is progressively advanced, enabling precise, deep, and personalized pulsed-field ablation of cardiac tissue. This is particularly suitable for treating cardiac diseases such as atrial fibrillation, significantly improving treatment precision and efficacy while significantly reducing surgical risks and enhancing safety, thus providing patients with greater safety and quality of life.

[0065] The following provides more detailed embodiments to illustrate the application of the electrodes, their preparation methods, and their usage methods in the treatment of cardiac diseases such as atrial fibrillation.

[0066] I. Electrode Design and Fabrication

[0067] 1. Design Phase:

[0068] Based on the ablation requirements of cardiac tissue, the size, shape, and zonal layout of the electrodes are designed, such as... Figure 1 and Figure 2 As shown. Each electrode zone is designed to be activated independently to adjust the distribution and intensity of the electric field, ensuring precise control of the ablation range.

[0069] 2. Material selection:

[0070] Select suitable materials to construct each layer of the electrode:

[0071] Substrate and encapsulation layers: Insulating materials such as polyimide, parylene, SU-8 photoresist, or silk protein are used;

[0072] Conductive layer: using conductive materials such as gold, platinum, copper, graphene, and liquid alloys;

[0073] Electrode modification layer: High-performance materials such as platinum black, iridium oxide, MXenes, or polyethylene dioxythiophene-polystyrene sulfonic acid are used.

[0074] 3. Micro / nano fabrication:

[0075] Reference Figure 3The fabrication process involves first creating a base layer on a silicon wafer, followed by the sequential addition of an adhesion layer and a conductive layer. Photolithography and dry etching techniques are used to pattern the conductive layer, forming a conductive layer with a specific shape and partitions. An encapsulation layer is then added to the conductive layer, patterned using photoresist, and dry etching is used to expose the electrode points, pads, and the overall outline of the electrode devices. An electrode modification layer is then added to the electrode points to enhance the electrochemical performance and biocompatibility of the electrodes.

[0076] II. Control Strategies for the Ablation Process

[0077] 1. Layer-by-layer activation procedure: Refer to Figure 5 and Figure 6 Based on the specific conductivity of the heart tissue and the expected ablation depth, the control unit activates electrode pairs with different configurations layer by layer through a predetermined program, thereby achieving precise layer-by-layer ablation.

[0078] 2. Optimization of electrical pulse parameters: During each ablation step, the electrical pulse parameters are dynamically optimized based on the real-time monitoring of changes in the electrical impedance inside the heart tissue to ensure the accuracy and safety of the ablation effect.

[0079] In atrial fibrillation treatment, the initial activation configuration of the electrode pairs is first determined based on the initial impedance of the cardiac tissue. As the ablation process progresses, monitored changes in tissue conductivity guide subsequent electrode pair activation strategies and adjustments to electrical pulse parameters, gradually achieving the target ablation depth and extent in the cardiac tissue.

[0080] To illustrate the technical effects of the embodiments of the present invention, a conventional electrode without a multi-level layered structure is used as a comparison. Conventional pulsed field ablation creates a single lesion based on a single ablation, and cannot achieve transmural damage, such as... Figure 7 As shown.

[0081] During ablation, the electrical impedance of the scar tissue decreases. This invention proposes a layer-by-layer tissue ablation technique based on impedance feedback during the ablation process, which differs from the electrodes and ablation methods of traditional pulsed field ablation. For example... Figure 5 and Figure 7As shown, by activating different zoned electrode points layer by layer, ablation points of different sizes and depths can be achieved. First, an ablation scar I is created through the first ablation process, which has a large area but insufficient depth. By detecting the tissue impedance within the electrode area, the electrode pairs within the ablation scar I are activated under impedance feedback, thus obtaining ablation scar II. Since the tissue conductivity in ablation scar I generated in the first step decreases and the area of ​​the activated electrode pairs shrinks, the resulting ablation scar II has a smaller area but a significantly increased depth. Furthermore, similarly, under the premise of impedance feedback, the electrode pairs within the area of ​​ablation scar II are activated, thus obtaining ablation scar III. Since the tissue conductivity in the ablation scars generated in the first two steps decreases and the area of ​​the activated electrode pairs shrinks further, the final ablation scar III has a further smaller area and achieves transmural damage to cardiac tissue, thereby achieving progressive focusing of the electric field and high-precision and deep pulsed field ablation.

[0082] The embodiments of the present invention, through a unique partitioned and layer-by-layer activated electrode design, can precisely control the distribution and intensity of the pulse field; using micro-nano fabrication technology to prepare partitioned hierarchical electrodes or electrode arrays, different configurations of electrode pairs can be activated by a control unit to generate an adjustable electric field direction and intensity; through layer-by-layer activation adjustment and real-time monitoring and dynamic adjustment strategies, the electrode achieves deep tissue penetration at lower voltages, enabling precise, deep, and personalized pulse field ablation of cardiac tissue while reducing damage to surrounding healthy tissues, greatly improving the safety and effectiveness of cardiac disease treatment.

[0083] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention. The above preferred features can be used in any combination without conflict.

Claims

1. An electrode for pulsed field ablation of cardiac tissue, characterized in that, The electrode has a multi-level partition structure, with each partition containing at least one pair of independently activatable electrodes. The cathodes and anodes of the electrode pairs are arranged in an alternating manner, and the distance between the anode and cathode in the electrode pairs gradually decreases from the outside to the inside. By activating different electrode pairs, the direction and intensity of the electric field can be adjusted to meet the ablation needs of different depths and ranges of cardiac tissue. In the multi-level partition structure, the number of partitions is determined according to the distance between the anode position and the electrode center. The partition where the anode is closest to the electrode center is the primary structure, and the distance between the anode and the cathode is the largest in the electrode pair of the primary structure. The anode of the primary structure is located at the center of the electrode. The anodes of the multi-level partitioned structure are arranged sequentially from the center of the electrode in ascending order of level. The anodes of different levels are interleaved. The cathode of the multi-level partitioned structure is located on the outer ring of the electrode. The cathodes of different levels are spaced apart.

2. The electrode for pulsed field ablation of cardiac tissue according to claim 1, characterized in that, The shape and arrangement of the electrode pairs in each partition are determined according to the electric field distribution pattern.

3. The electrode for pulsed field ablation of cardiac tissue according to claim 1, characterized in that, The electrode comprises, from bottom to top, a lower insulating layer, an electrode layer, an upper insulating layer, and an electrode modification layer. The electrode layer is used to apply pulsed electrical signals to the heart tissue and simultaneously record the electrical impedance of the heart tissue before and after each pulsed ablation.

4. The electrode for pulsed field ablation of cardiac tissue according to claim 3, characterized in that, It has at least one of the following characteristics: The electrode layer is made of any one of gold, platinum, copper, graphene, and liquid alloys. The material of the electrode modification layer is selected from any one of platinum black, iridium oxide, MXenes and polyvinyl dioxythiophene-polystyrene sulfonic acid; The materials for the electrode's base layer and encapsulation layer are selected from any one of polyimide, parylene, SU-8 photoresist, and silk protein.

5. A method for preparing an electrode for pulsed field ablation of cardiac tissue according to any one of claims 1-4, characterized in that, include: Fabricate a substrate layer on a substrate material; An adhesive layer is fabricated on the base layer, then a conductive layer is fabricated, and finally the conductive layer is patterned. An encapsulation layer is fabricated on the conductive layer; Spin-coat photoresist, pattern the photoresist using photolithography, and use dry etching to etch and expose the electrode points, pads, and overall outline of the electrode devices. The electrode device is released, and an electrode modification layer is fabricated on the electrode point to obtain an electrode for pulsed field ablation of cardiac tissue.

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