CN113648052B

CN113648052B - Local pulse electric field ablation electrode catheter

Info

Publication number: CN113648052B
Application number: CN202110963239.9A
Authority: CN
Inventors: 朱晓林
Original assignee: Sichuan Jinjiang Electronic Medical Device Technology Co ltd
Current assignee: Sichuan Jinjiang Electronic Medical Device Technology Co ltd
Priority date: 2021-08-20
Filing date: 2021-08-20
Publication date: 2023-01-31
Anticipated expiration: 2041-08-20
Also published as: CN113648052A; CN115844520A

Abstract

The invention relates to the field of medical electrophysiology catheter technology and cardiac electrophysiology ablation, in particular to a local pulse electric field ablation electrode catheter, which comprises an ablation head end 1, a near-end tube body 3 and a handle assembly 9, wherein the ablation head end 1 is connected with the handle assembly 9 through the near-end tube body 3, the ablation head end 1 comprises a head electrode 11, a matching electrode and a supporting tube body 2, the head electrode 11 is attached to the farthest end of the supporting tube body 2, the matching electrode is arranged on the supporting tube body 2 at a preset interval distance, and the head electrode 11 is matched with the matching electrode to generate a high-voltage pulse electric field; the area ratio K of the surface area of the matching electrode to the surface area of the head electrode 11 is in the range of 1. Ltoreq. K.ltoreq.3. The ablation head end applies a high-voltage pulse energy source to target tissues to realize efficient and accurate ablation, and the catheter with the ablation head end can reach various complex, fine and closed tissue structures and the interiors of the tissues.

Description

Local pulse electric field ablation electrode catheter

Technical Field

The invention relates to the field of medical electrophysiology catheter technology and cardiac electrophysiology ablation, in particular to a local pulsed electric field ablation electrode catheter.

Background

The pulsed electric field is always researched by scholars at home and abroad as an efficient and safe ablation energy source, and the pulsed electric field technology has made a huge progress in recent years, especially in the field of tumor ablation, and the application of the pulsed electric field ablation principle to the field of cardiac ablation is also the direction of research at home and abroad at present.

Pulsed electric field techniques are techniques in which a brief high voltage applied to the tissue can produce a local high electric field of several hundred volts per centimeter that disrupts the cell membrane by creating pores in the cell membrane. The application of an electric field at the membrane above the cell threshold causes the pores not to close, and this electroporation is irreversible, thereby allowing the exchange of biomolecular material across the membrane, resulting in cell necrosis or apoptosis. After the former pulse string with positive polarity is finished, a negative pulse string with the same pulse width and equal field intensity is applied next to the former pulse string with positive polarity, so that action potential induced by the positive pulse can not be generated sufficiently, action potential is developed in the reverse direction due to the negative pulse, and nerve stimulation caused by an electric field is greatly reduced.

Because different tissue cells have different threshold values for voltage penetration, the high-voltage pulse technology can selectively treat the myocardial cells (the threshold value is relatively low) without influencing other non-target cell tissues (such as nerves, esophagus, blood vessels and blood cells).

Currently, the design of catheters presents the following problems:

1. catheters have difficulty in accurately, centrally, and locally applying a high voltage pulsed energy source to the target tissue.

2. An effective electrode acted by a pulse electric field is at least two electrodes with opposite polarities, and how to arrange a plurality of electrodes in a local area to adapt to various complex and fine organizational structures is a problem to be solved urgently.

Disclosure of Invention

In order to overcome the problems, the invention provides a local pulse electric field ablation electrode catheter, which improves the arrangement of electrodes on the catheter to adapt to the output of high-voltage pulse signals.

In order to achieve the above purpose, the invention provides the following technical scheme:

a local pulsed electric field ablation electrode catheter comprises an ablation head end 1, a near-end tube body 3 and a handle assembly 9, wherein the ablation head end 1 is connected with the handle assembly 9 through the near-end tube body 3, the ablation head end 1 comprises a head electrode 11, a matching electrode and a supporting tube body 2, the head electrode 11 is attached to the farthest end of the supporting tube body 2, the matching electrode is arranged on the supporting tube body 2 at a preset interval distance, and the head electrode 11 is matched with the matching electrode to generate a high-voltage pulsed electric field;

and the area ratio K of the surface area of the matching electrode to the surface area of the head electrode 11 is in the range of 1. Ltoreq. K.ltoreq.3.

Through the arrangement, when high-voltage pulse energy discharges between the head electrode 11 and the matching electrode to form a high-voltage pulse electric field, the obtained high-voltage positive pulse or negative pulse can act on the tissue attached to the ablation head end 1, and the high-voltage pulse energy source is accurately, intensively and locally applied to the target tissue.

The area ratio K between the ablation depth and the surface area of the head electrode 11 and the surface area of the matching electrode is close to a linear relationship, as shown in fig. 3, that is, if a larger ablation depth is desired, the area ratio K can be increased, where K is the surface area of the matching electrode divided by the area of the head electrode (the matching electrode may be one ring electrode a12, two ring electrodes a12 and B, or three ring electrodes A, B, C), that is, on the premise of the same head electrode area, the larger the surface area of the matching electrode is, the larger the ablation lesion degree is, the larger the ablation range is, the voltage of the high-voltage pulse train is considered to be 500V-5000V, and the corresponding K value range is between 1 and 20. More preferably, the area ratio K is in the range of 1. Ltoreq. K.ltoreq.3.

The area ratio K value is selected to be 1-3, and excessive K value difference can cause that energy is excessively concentrated on the head electrode 11, so that the electric field intensity or current density on the head electrode 11 is too high to generate ionization phenomenon, and the problems of bubble, tissue burning and the like are generated after ionization.

In a preferred embodiment of the present invention, the distance between the electrodes is 0.5 to 3mm.

The electric field intensity is maximum on the surface of the electrode and gradually attenuates outwards, and meanwhile, the field intensity gradually attenuates from the electrode to the center of the electrode, so that the optimal arrangement of the electrode spacing is needed in order to ensure that enough field intensity reaches the expected ablation depth and the electric field intensity in the middle of the electrode is effective. Too large space cannot form continuous ablation zone and the ablation head end 1 is too long, too small space field intensity is concentrated and easy to generate ionization phenomenon, and too small electrode diameter field intensity is concentrated and easy to generate ionization phenomenon.

The field intensity analysis of different intervals is carried out under the condition that the voltage, the electrode and the medium are the same, the field intensity of the center between the electrodes is reduced along with the increase of the intervals, the field intensity of the edges of the electrodes is reduced along with the increase of the intervals, the field intensity is unchanged after a certain distance is reached, the electrode interval is selected to be 0.5-3mm by integrating the field intensity of the center, the field intensity of the edges and the safety, the field intensity of the undersized electrode interval is overlarge, the requirement on an insulating material is extremely high, therefore, the minimum interval is limited to be 0.5mm (the minimum interval is set according to the fact that the PEEK material is not broken down), the change of the electrode edge field intensity caused by the intervals is not obvious after the interval reaches 3mm, meanwhile, the problem of the length of the head end is considered, the overlong head end is not convenient to control, and therefore, the maximum interval is limited to be 3mm.

As a preferable scheme of the invention, the matching electrode is a ring electrode, the ring electrode is arranged in the axial direction of the supporting tube body (2), and the surface area of the head electrode (11) is equal to that of the ring electrode closest to the head electrode.

Due to the equal area, when the head electrode 11 and the ring electrode discharge between the electrodes, the applied energy can be equally divided, and the problems of ionization and the like caused by the excessive concentration of the energy on one side are avoided.

As a preferable aspect of the present invention, the matching electrode may be provided as a plurality of disk-shaped electrodes, and attached to the ablation tip 1 around the head electrode 11 with the head electrode 11 as the center.

Under the arrangement, when high-voltage pulse energy is applied between the head electrode 11 and the matching electrode, the high-voltage pulse energy can be concentrated at the ablation head end 1, so that the concentrated ablation intensity is increased, and an operator can accurately ablate point-to-point tissues to avoid damaging surrounding healthy tissues.

When the matching electrode is arc-shaped and takes the head electrode 11 as the center, the ablation head end 1 attached around the head electrode 11 is also provided with a second matching electrode which is an annular electrode and arranged on the axial direction of the ablation head end 1, and an insulating component 23 is arranged between the second matching electrode and the matching electrode. Under this kind of design, the matching electrode has contained two kinds of structures of circular-arc electrode and ring electrode, has compromise ring electrode deepening and has ablated the two kinds of characteristics of degree of depth and circular-arc electrode concentration and have ablated the energy, has increased the scene that ablation head end 1 was suitable for.

In a preferred embodiment of the present invention, the head electrode 11 has an irrigation hole 111, and the ablation head 1 is internally provided with a circulation passage for irrigating a cooling liquid. The irrigation is applied during ablation, so that the instantaneous ionization phenomenon caused by overhigh electric field intensity around the electrode during discharging can be effectively avoided, and the ablation is safer. The perfusion inner circulation form is formed to continuously reduce the surface temperature of the electrode, so that the instantaneous ionization phenomenon caused by overhigh electric field intensity around the electrode during discharging can be effectively avoided, and the cardiac load increased by the perfusion liquid in the heart is avoided.

As a preferable aspect of the present invention, the flow rate of the cooling liquid in the internal circulation passage is adjusted according to the magnitude of the high-pressure pulse energy. Because the corresponding relation between the amplitude of the energy and the flow velocity of the cooling liquid is established, the flow velocity of the cooling liquid can be directly adjusted through the amplitude, the adjusting speed of the flow velocity of the cooling liquid is improved, the surface temperature of the electrode can be timely adjusted, and the ionization phenomenon is avoided.

Further, the head electrode 11 is provided with a temperature sensor 17, and the flow rate of the cooling liquid in the internal circulation passage is controlled based on the detected temperature of the temperature sensor 17.

When adjusting the coolant liquid through energy amplitude, can also adopt temperature sensor 17 real-time supervision to melt head end 1 temperature, when detecting the high temperature when discharging, can increase the perfusion flow to reach better perfusion cooling effect, when monitoring the high temperature unusual simultaneously, also can feed back equipment system and stop discharging.

Further, the proximal tubular body 3 is a braided tubular body. The material of the braided tube body is formed by weaving polyurethane, PEBAX material and stainless steel wires, and the braided tube body has good torque response and support. The handle assembly 9 arranged at the near end of the near end tube body 3 bends the far end tube body 8.

Further, still include distal end body 8, distal end body 8 is connected in near-end body 3 and handle components 9, and distal end body 8 is multicavity structure, and the inside magnetic positioning sensor who is used for calculating the crooked form that shows distal end body 8 that places. For calculating and displaying the bending shape of the distal tube body 8.

Compared with the prior art, the invention has the beneficial effects that:

1. the ablation head end of the invention is designed to accurately apply a high-voltage pulse energy source to target tissues, so that efficient and accurate ablation is realized, and the catheter with the ablation head end can reach various complex, fine and closed tissue structures and the interiors of the tissues.

2. The high-voltage pulse energy is accurately and effectively transmitted and applied to the target tissue, the operation time is greatly shortened, the high-voltage pulse energy can selectively ablate the target tissue, and the complications are reduced.

Description of the drawings:

FIG. 1 is a schematic view of a catheter in accordance with an embodiment 1 of the present invention;

FIG. 2 is a schematic view of a catheter tip according to example 1 of the present invention;

fig. 2.1 is a schematic view of the head end of the catheter (head electrode with perfusion hole) in embodiment 1 of the present invention;

FIG. 3 is a graph showing the relationship between the electric field and the electrode spacing in example 1 of the present invention;

FIG. 4 is a graph showing the relationship between the ablation depth and the electrode area ratio in example 1 of the present invention;

FIG. 5 is an analysis diagram of the ablation electric field of a plurality of electrodes at the rear end of the head electrode in embodiment 1 of the present invention;

FIG. 6 is an analysis of the head electrode and two-electrode discharge ablation electric field in embodiment 1 of the present invention;

fig. 7 is a schematic view illustrating the pressure function and the magnetic positioning function of the ablation head in embodiment 1 of the present invention;

FIG. 8 is a schematic view of the ablation head end curvature in embodiment 1 of the present invention;

fig. 9 is a schematic view of an ablation tip embodiment 2 of example 2 of the present invention;

fig. 9.1 is a schematic diagram of a preferred mode of an embodiment 2 of an ablation tip in embodiment 2 of the present invention;

fig. 10 is a schematic cross-sectional view of an ablation tip embodiment 2 of example 2 of the present invention;

fig. 10.1 is a schematic diagram of the anode and cathode distribution of an ablation head embodiment 2 in example 2 of the present invention;

FIG. 11 is a schematic diagram of a biphasic pulse configuration according to the invention;

FIG. 12 is a schematic view of the present invention for adding an internal circulation irrigation fluid.

Reference numerals: 1. the ablation head comprises an ablation head end, a supporting tube body, a proximal tube body, a pressure sensor, a front magnetic positioning sensor, a rear magnetic positioning sensor, a traction assembly, a distal tube body, a handle assembly, a head electrode, a 111 perfusion hole, a ring electrode A, a ring electrode B, a ring electrode C, a water inlet pipe, a water outlet pipe, a temperature sensor, a 1111 head electrode cavity channel, a 1112 ring electrode A cavity channel, a 1113 ring electrode B cavity channel, a 1114 ring electrode C cavity channel, a 22 multi-polar ablation head end, a 23 insulating member, a 233 annular electrode belt-cathode, a 221, an ablation electrode-anode, a 2221 ablation electrode-cathode, a 2222 ablation electrode-cathode and a 222n ablation electrode-cathode.

Detailed Description

The present invention will be described in further detail with reference to test examples and specific embodiments. It should be understood that the scope of the above-described subject matter is not limited to the following examples, and any techniques implemented based on the disclosure of the present invention are within the scope of the present invention.

Example 1

As shown in fig. 1 and 2, the ablation electrode catheter mainly comprises an ablation head end 1, a near-end tube body 3 and a handle assembly 9, wherein the ablation head end 1 is arranged at the far end of the near-end tube body 3, a head electrode 11, a ring electrode A12, a ring electrode B13 and a ring electrode C14 are sequentially distributed at the ablation head end 1, the head electrode 11 is cylindrical, a chamfer is arranged between the end surface and the side wall, the safety problems of ionization and the like caused by excessive concentration of energy when discharge is caused by sharp edges and corners are avoided, and the ring electrode A12 and the head electrode 11 are arranged at an interval of 0.5-3mm.

The electric field intensity is maximum on the surface of the electrode and gradually attenuates outwards, and meanwhile, the field intensity gradually attenuates from the electrode to the center of the electrode, so that the optimal parameter value of the distance between the electrodes is needed in order to ensure that enough field intensity exists in the depth and the electric field intensity in the middle of the electrode is effective. Too large space can not form continuous ablation zone and make ablation head end 1 overlong, ionization phenomenon easily takes place in the field intensity concentration of undersize interval, ionization phenomenon easily takes place in the field intensity concentration of undersize electrode diameter.

The field intensity analysis of different distances is carried out under the condition that the voltage, the electrode and the medium are the same, a relation graph of an electric field and the electrode distance is given in figure 3, as can be seen from the graph, the field intensity in the center of the electrode is reduced along with the increase of the distance, the field intensity at the edge of the electrode is reduced along with the increase of the distance, the field intensity is unchanged after a certain distance is reached, the electrode distance is selected to be 0.5-3mm by integrating the field intensity in the center and the edge field intensity and the safety, the field intensity of the undersized electrode distance is overlarge and has extremely high requirement on an insulating material, therefore, the minimum distance of 0.5mm is limited (the minimum distance is set according to the fact that the PEEK material is not broken down), the change of the electrode edge field intensity caused by the distance is not obvious after the distance reaches 3mm, meanwhile, the problem of the length of the head end is considered, the overlong head end is not convenient to control, and therefore, the maximum distance is limited to be 3mm.

Preferably, the surface area of the ring electrode a12 is equal to the surface area of the head electrode 11, and thus, when the discharge is performed between the head electrode 11 and the ring electrode a12, the applied energy can be equally divided due to the equal surface areas, thereby avoiding the problems of ionization and the like caused by the excessive concentration of the energy on one side. The head electrode 11 and the ring electrode A12 can be partially ablated integrally during ablation, an ablation electric field analysis schematic diagram is shown in fig. 5, the head electrode 11 and the ring electrode are closer, partial ablation can be realized during discharge ablation, the ablation depth is increased along with the increase of the applied voltage amplitude, and the local bipolar pulse electric field ablation can be used for ablating a focus region in a targeted manner, so that the surrounding healthy tissues are prevented from being damaged. For the lesion tissue area with larger ablation depth, a head electrode 11 and a ring electrode A, B, C can be used for discharging, that is, the head electrode 11 serves as an anode, the ring electrode A, B, C serves as a cathode, and the electric field analysis of the discharge ablation is shown in fig. 5, the ablation depth is obviously increased, the effective ablation area is in a spindle shape and is concentrated at the head end, referring to fig. 4, the relation between the ablation depth and the electrode area ratio, that is, if a larger ablation depth is desired, the area ratio K can be increased, K is the area (the sum of the ring electrodes A, B, C) divided by the area of the head electrode 11, that is, on the premise of the same head electrode 11 area, the larger the sum of the ring electrodes A, B, C is, the ablation damage degree is larger, the ablation range is larger, since the areas of the ring electrode a12 and the head electrode 11 are equal (considering the safety when only two electrodes are used for discharging), the method for increasing the K value is that the surface areas of the ring electrode B13 and the ring electrode C14 are increased, even more cathodes (ring electrodes), the K value can be 1-20, the K value is preferably 1-3, the difference between the electrode K is selected, and the head electrode can cause the problem of excessive ionization and the head electrode can be generated, the head electrode can be over-head ionization phenomenon, and the head ionization phenomenon of the head electrode can be generated. The electrode is made of platinum-iridium alloy (Pt/Ir) and stainless steel 304V. The head electrode 11 and the ring electrode are fixedly provided on the support tube 2, and the support tube 2 is preferably made of PEEK (polyetheretherketone) material and can withstand high-voltage energy discharged between the electrodes.

Furthermore, in order to adapt to the amplitude of the output of the high-voltage pulse signal, the size of the surface area, the area ratio and the spacing distance need to be comprehensively considered when the electrodes are arranged, the three need to be arranged in a matched mode, and the amplitude of the high-voltage pulse signal can be adapted without depending on a certain parameter.

Table 1 shows the correspondence among the high-voltage pulse signal energy amplitude, the electrode gap, and the area ratio, which are given based on the theoretical analysis and the actual verification values of the electric field, under which the maximum depth field intensity can be generated while ensuring that no ionization occurs between the electrodes.

TABLE 1 correspondence between high-voltage pulse signal energy amplitude, electrode spacing and area ratio

For example, if the range of the energy amplitude output of the high-voltage pulse signal is 500-1000V, the electrode spacing is selected within 0.5-1 mm, and the area ratio is selected within 3-20. If the range of the energy amplitude output of the high-voltage pulse signal is 1000-1800V, the electrode distance is selected within 1-1.5 mm correspondingly, and the area ratio is selected within 2.5-3.

The catheter has an electrode cooling function, one mode is to melt head end 1 open type perfusion cooling electrode, the other mode is inner loop cooling electrode, as shown in fig. 2.1, melt head end 1 and can set up perfusion hole 111, apply when melting and pour into, can effectively avoid the electric field intensity is too high around the electrode when discharging and lead to instantaneous ionization phenomenon, make to melt safer (probably produce the bubble behind the ionization phenomenon, when melting in the heart, especially the left atrium easily arouses the air cock problem when melting). As shown in fig. 12, the head electrode 11 and the ring electrode are provided with internal circulation channels, that is, the cooling liquid can be poured into the head electrode cavity 1111, the ring electrode a cavity 1112, the ring electrode B cavity 1113 and the ring electrode C cavity 1114 through the water inlet pipe 15, and then the cooling liquid is discharged out of the electrode cavity through the water outlet pipe 16, so as to form a pouring internal circulation form, so as to continuously reduce the surface temperature of the electrode, and to more effectively avoid the instantaneous ionization phenomenon (which may generate bubbles after the ionization phenomenon, and especially when the left atrium ablates, the air embolism problem is easily caused when the left atrium ablates) caused by the overhigh electric field strength around the electrode during discharging, and simultaneously avoid the increase of the cardiac load caused by the liquid poured into the heart.

The electrode cooling function can be adjusted with the amplitude of the released pulse ablation energy, as shown in table 2:

TABLE 2 relationship table of coolant flow rate and energy amplitude

As shown in fig. 7, the ablation head end 1 is provided with a temperature sensor 17, the temperature sensor 17 can monitor the temperature of the ablation head end 1 in real time, when the temperature is detected to be too high during discharging, the perfusion flow can be increased to achieve a better perfusion cooling effect, and meanwhile, when the temperature is detected to be too high and abnormal, the equipment system can also be fed back to stop discharging.

As shown in fig. 8, the catheter is linear as a whole, and can reach various tissue parts of the heart at will by matching with the function of adjustable bending, so as to adapt to various focus parts. The near end is provided with a near end tube body 3, the near end tube body 3 is a braided tube body, the materials are formed by weaving polyurethane, PEBAX materials and stainless steel wires, and the near end tube body has good torque response and support. A handle assembly 9 is arranged at the near end of the near-end tube body 3, and the handle assembly 9 bends the far-end tube body 8.

As shown in fig. 8, the distal tube 8 is a multi-lumen structure for placing the magnetic positioning sensor a and the traction assembly 7, the distal tube 8 can be bent under the control of the traction assembly 7, and the distal tube 8 is preferably a polyurethane braided tube structure. The ablation head end 1 is provided with a traction assembly 7, one end of the traction assembly 7 is arranged at the head end of the catheter, the other end of the traction assembly 7 is arranged at a near-end handle assembly 9, the traction component is arranged on the inner side of the bending direction of the catheter, the traction assembly 7 is far away from the axis of the catheter, and a front-end magnetic positioning sensor 5 and a rear-end magnetic positioning sensor 6 are respectively arranged at the far end and the near end of a far-end pipe body 8 and used for calculating and displaying the bending form of the far-end pipe body 8.

Example 2

As shown in fig. 9 and 9.1 and fig. 10 and 10.1, in embodiment 2, the ablation electrode-anode 221 is located at the topmost end of the multi-polar ablation tip 22, the ablation electrode-cathodes (2221-222 n) are uniformly distributed on the insulating member 23 at intervals in a ring shape, high-voltage pulse energy is applied between the cathodes and the anodes, and the area ratio K between the ablation electrode-cathodes and the ablation electrode-anode 221 is selected to be 1-3, and can be specifically configured according to adaptability to achieve a desired depth. The design of the embodiment 2 mainly solves the problem that the ablation electrode is more intensively arranged at the ablation head end 1, so that the surrounding healthy tissues are prevented from being damaged. The distance between the anode and the cathode is controlled to be 0.5-3mm, the number of the anodes is 1, the number of the cathodes is multiple, and the surface area of a single cathode and the surface area of an anode electrode can be equal to ensure higher safety. The ablation electrode-cathode may also be an annular electrode strip 233 attached to the insulating member 23.

As shown in fig. 11, the applied energy source is a high voltage pulse train, the pulse is a biphasic pulse, which can effectively reduce the stimulation response of the patient during ablation, the pulse train has a voltage of 500V-5000V, and since different tissue cells have different threshold values for voltage penetration, the high voltage pulse technology can be used for selectively treating the myocardial cells (the threshold value is relatively low), and does not affect other non-target cell tissues (such as nerves, esophagus, blood vessels, blood cells). The high voltage pulse waveform is released during the absolute refractory period of the cardiac cycle to avoid interruption of the heart's normal rhythm. The energy may be released between 70ms and 100ms after the start of the R-wave is detected. After ablation, the instant ablation effect can be determined through EGM signal change collected between the head electrode groups.

Animal experiments and clinics prove that effective ablation needs the electrode to be attached to the tissue correctly, high-voltage pulse energy is applied after the electrode is attached to the tissue correctly, the correct attachment can be judged by comprehensively judging the attachment condition and the attachment pressure between the electrode and the tissue according to the position relation between the electrode and the tissue, the impedance between the electrode and the tissue and an EGM signal acquired between the electrodes, and as shown in fig. 7, a pressure sensor 4 is arranged in an ablation head end 1, so that the attachment pressure between the ablation head end 1 and the tissue can be monitored in real time. The immediate effect after ablation can be judged by an electric potential diagram, the impedance reduction amplitude between the electrode and the tissue and the change of the conduction sequence.

In addition, the current clinical ventricular septal volume reduction mainly comprises two modes of surgical ventricular septal resection and ventricular septal alcohol ablation. Among them, surgical compartmental resection is generally suitable for young patients, but has the disadvantages of great surgical trauma and high risk; the ventricular septal alcohol ablation is suitable for patients with advanced diseases and serious complications, but depends on the proper septal artery, and the uncertainty of the ablation range, so that the chance of reoperation is greater, and the ventricular septal alcohol ablation is only recommended clinically as an alternative to surgical ventricular septal surgery at present. Therefore, the invention can enter the interior of the myocardial tissue for ablation, and the internal circulation mode is selected because of the closed environment during the ablation of the interior of the myocardial tissue.

While there have been shown and described what are at present considered the fundamental principles and essential features of the invention and its advantages, it will be apparent to those skilled in the art that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, the embodiments do not include only one independent technical solution, and such description is only for clarity, and those skilled in the art should take the description as a whole, and the technical solutions in the embodiments may be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A local pulsed electric field ablation electrode catheter comprises an ablation head end (1), a near-end tube body (3) and a handle assembly (9), wherein the ablation head end (1) is connected with the handle assembly (9) through the near-end tube body (3), the ablation head end (1) comprises a head electrode (11), a matching electrode, a second matching electrode and a supporting tube body (2), and the local pulsed electric field ablation electrode catheter is characterized in that,

the head electrode (11) is attached to the farthest end of the supporting tube body (2), the matching electrode and the second matching electrode are arranged on the supporting tube body (2) at a preset interval distance,

the matching electrode is an annular electrode belt or a plurality of disc-shaped electrodes, and the matching electrode takes the head electrode (11) as the center and is attached to the ablation head end (1) around the head electrode (11);

the second matching electrode is an annular electrode, the second matching electrode is arranged in the axial direction of the ablation head end (1), and an insulating component (23) is arranged between the second matching electrode and the matching electrode;

the head electrode (11) is matched with the matching electrode and the second matching electrode to generate a high-voltage pulse electric field; and the area ratio K of the surface areas of the matching electrode and the second matching electrode to the surface area of the head electrode (11) is in the range of 1 to 3; the spacing distance ranges from 0.5mm to 3mm.

2. The ablation electrode catheter of claim 1, wherein the head electrode (11) has a surface area equal to that of the ring electrode nearest thereto.

3. The partial electric field ablation electrode catheter as claimed in any one of claims 1 to 2, wherein the head electrode (11) is provided with an irrigation hole (111), and an internal circulation passage for irrigating a cooling liquid is provided inside the ablation head end (1).

4. The partial electric field ablation electrode catheter according to claim 3, wherein a flow rate of the cooling liquid in the internal circulation passage is adjusted according to the magnitude of the high voltage pulse energy.

5. The partial electric field ablation electrode catheter as defined in claim 4, wherein a temperature sensor (17) is provided on said tip electrode (11), and the flow rate of the cooling liquid in the internal circulation passage is controlled based on the detected temperature of said temperature sensor (17).

6. The catheter as claimed in claim 5, wherein the proximal tube (3) is a braided tube.

7. The ablation electrode catheter of claim 6, further comprising a distal tube (8), wherein the distal tube (8) is connected to the proximal tube (3) and the handle assembly (9), the distal tube (8) is a multi-lumen structure, and a magnetic position sensor for calculating and displaying the bending form of the distal tube (8) is arranged inside the distal tube (8).