Basket electrode assembly, basket-shaped catheter, basket catheter system, and basket catheter calibration method

Abstract

Embodiments of the present application relate to the technical field of electrophysiological catheters, and in particular to a basket-shaped catheter. A basket electrode assembly of the basket-shaped catheter comprises: splines, which in a free state have a curved structure; a proximal fixing seat, fixedly connected to proximal ends of the respective splines; and a distal fixing seat, fixedly connected to distal ends of the respective splines. A seat lead-out wire provided on the distal fixing seat comprises an elastic telescopic section, which helps to reduce the difficulty of processing the basket electrode assembly. The correlation between an axial force value of the basket electrode assembly and a variation ΔX in the distance between the proximal and distal ends, as well as a conversion relationship between an apposition angle between the basket electrode assembly and a target tissue and the axial force value are utilized, thereby enabling measurement of an apposition force of the basket-shaped catheter. Ablation electrodes on adjacent splines are circumferentially staggered along a basket framework, increasing the spacing between the ablation electrodes and achieving electric field convergence. An electrode fixing segment provided on each spline comprises a weakening structure for weakening the electrode fixing segment, thereby facilitating deformation of the basket framework.

Description

Basket electrode assembly, basket-shaped catheter, basket-shaped catheter system and basket-shaped catheter calibration method

[0001] Cross-reference to related applications

[0002] This application claims priority to the following applications, the entire contents of which are incorporated herein by reference:

[0003] The application date is January 6, 2025, the application number is CN202510020684X, and the title is: Chinese Invention Patent Application for Basket Electrode Assembly and Basket-shaped Conduit;

[0004] The application date is January 6, 2025, the application number is CN2025100206746, and the title is: Chinese Invention Patent Application for a Net Basket Conduit System and Net Basket Conduit Calibration Method;

[0005] The application date is January 6, 2025, the application number is CN202510020652X, and the title is: Chinese Invention Patent Application for an Ablation Catheter and Basket Skeleton;

[0006] The application date is January 6, 2025, the application number is CN2025100206619, and the title is: Chinese Invention Patent Application for an Ablation Catheter and its Electrode Assembly. Technical Field

[0007] This application relates to the field of electrophysiological catheter technology, and in particular to basket-shaped catheters. Background Technology

[0008] Pulsed electric field ablation (PFA), a novel technique for treating atrial fibrillation, involves using a strong electric field for a short period to induce irreversible electroporation of cells, leading to cell death. This non-thermal ablation method has been successfully developed to treat arrhythmias. Surgical treatment of arrhythmias often relies on ablation catheters, with basket-shaped ablation catheters being one type.

[0009] Using a spherical basket-shaped ablation catheter, the electric field generated by short-duration high-voltage pulses released from its electrodes can ablate target tissues, achieving the clinical treatment of arrhythmias. The spherical catheter tip allows the basket electrode assembly to better adhere to the local tissue, resulting in better ablation effects. Simultaneously, the corresponding basket structure allows for greater flexibility during adhesion, buffering pressure and reducing stress on the target tissue. Currently, spherical basket structures are relatively rare on the market, primarily because their splines experience significant stress during the expansion and contraction of the basket electrode assembly, leading to poor fatigue resistance and manufacturing difficulties. Furthermore, the electrodes on the splines require lead wires for power transmission, and the distal end of the basket-shaped catheter often needs to house functional components such as position sensors, which also require lead wires for power transmission. The lead wires passing through the splines further increase the difficulty of basket fabrication.

[0010] When ablation catheters are used clinically, if the real-time status of the tip electrode assembly's contact with the target tissue can be provided—such as the position, orientation, and contact force of the tip electrode assembly—it can better guide physicians in performing ablation procedures. Chinese patent application CN117100381A discloses a balloon catheter ablation system. The balloon catheter uses a compliant balloon body that can deform under axial pressure and / or deflect under lateral pressure. This characteristic, in conjunction with proximal and distal magnetic sensors, generates changes in axial spacing x and / or angle α. Simultaneously, by using a known first correspondence between the axial spacing x and the axial contact force of the balloon catheter, and / or a known second correspondence between the angle α and the lateral contact force of the balloon catheter, the corresponding contact force can be detected without the need for additional sensors for contact force detection, thus eliminating the need for additional space and cost. The aforementioned contact force detection method utilizes a compliant balloon body with relatively uniform elastic modulus in all directions. However, the deformation characteristics of the tip electrode assembly of the basket catheter are different from those of the balloon catheter, making it impossible to calculate the contact force based on the above-mentioned balloon catheter contact force detection method.

[0011] In addition, during ablation procedures, the basket-like catheter's framework should possess good flexibility, capable of adapting to deformation under pressure and effectively adhering to the target biological tissue (e.g., myocardial target tissue), thereby effectively blocking abnormal electrical conduction within the target biological tissue. In some cases, the basket framework is too rigid, and the portion of the basket framework that fixes the catheter electrode is not easily deformed, preventing the catheter electrode from adhering well to the tissue, reducing the ablation effect and increasing operational risks.

[0012] Furthermore, the electrode distribution and associated ablation parameters of the pulse ablation catheter directly affect the clinical ablation effect. Current pulse ablation catheters have a relatively dense electrode distribution, which, while providing good ablation results, also results in excessively strong electric fields between the electrodes. This can easily lead to electric arcs during discharge, causing barotrauma to local tissues and causing blood to coagulate on the electrode surface, thus affecting subsequent discharge effects. Summary of the Invention

[0013] This application is intended to solve at least one of the aforementioned technical problems.

[0014] In a first aspect, this application provides a basket electrode assembly, comprising:

[0015] Splines are distributed circumferentially along the basket electrode assembly and are elastically deformable. The splines are curved in the free state so that the basket electrode assembly is in an expanded state in the free state.

[0016] A proximal fixing seat is fixedly connected to the proximal end of each spline;

[0017] A remote fixing seat is fixedly connected to the remote end of each spline.

[0018] In some embodiments, the basket electrode assembly further includes a base lead wire, the distal end of which is connected to the distal fixing seat, and the base lead wire passes through the proximal fixing seat; the base lead wire includes an elastic telescopic section, at least a portion of which is located between the proximal fixing seat and the distal fixing seat, the elastic telescopic section being configured to change its size along the proximal-distal direction of the basket electrode assembly as the position of the distal fixing seat changes.

[0019] In some embodiments, the basket electrode assembly further includes a proximal position sensor and a distal position sensor respectively disposed on the proximal fixation base and the distal fixation base, the proximal position sensor and the distal position sensor being used to acquire the change in the proximal-distal distance of the basket electrode assembly.

[0020] Secondly, this application provides a basket-shaped catheter, including an operating handle, a tube body, and an electrode assembly connected sequentially from the proximal end to the distal end, wherein the electrode assembly is the basket electrode assembly described in any of the above claims.

[0021] Thirdly, this application provides another basket-shaped catheter, including the aforementioned basket electrode assembly. The basket electrode assembly includes: a basket skeleton, the basket skeleton including the splines, the splines including at least two; the basket skeleton has an expanded shape and a contracted state as the distal end of the splines approaches and moves away from the proximal end; the splines include elastically deformable segments, the elastically deformable segments being capable of elastic deformation as the distal end of the splines approaches and moves away from the proximal end; and an ablation electrode, the ablation electrode being fixed on the elastically deformable segments; the elastically deformable segments of two adjacent splines along the circumferential direction of the basket electrode assembly are respectively a first elastic segment and a second elastic segment; the ablation electrode on the first elastic segment is arranged close to the proximal end and away from the distal end, and the ablation electrode on the second elastic segment is arranged close to the distal end and away from the proximal end; the ablation electrode on the first elastic segment and the ablation electrode on the second elastic segment are offset along the circumferential direction of the basket skeleton.

[0022] Fourthly, this application provides a basket catheter system, including a processing device, an operating handle, a tube body, and a basket electrode assembly connected sequentially from the proximal end to the distal end. The basket electrode assembly is any of the basket electrode assemblies described above. The basket electrode assembly further includes a proximal position sensor and a distal position sensor respectively disposed on the proximal fixation seat and the distal fixation seat. The proximal position sensor and the distal position sensor are used to acquire the change in the proximal-distal distance of the basket electrode assembly. The proximal position sensor and the distal position sensor are connected to the processing device. The processing device is used to obtain the contact force between the basket electrode assembly and the target tissue based on the change in the proximal-distal distance, the known correspondence between the axial force value of the basket electrode assembly and the change in the proximal-distal distance, and the contact angle between the basket electrode assembly and the target tissue.

[0023] Fifthly, this application provides a method for calibrating a basket guide tube, comprising the following steps: Step 1, maintaining a detection angle between the axis of the proximal fixing seat of the basket electrode assembly and the detection surface of the pressure detection device; Step 2, applying an axial test pressure to the basket electrode assembly along the axis of the proximal fixing seat, causing the basket electrode assembly to abut against the detection surface of the pressure detection device, applying a fixing force value to the detection surface, and the pressure detection device detecting a contact force value perpendicular to the detection surface; Step 3, recording the following data: the proximal fixing seat of the basket electrode assembly... Step 4: Adjust the detection angle, repeat steps 2 and 3, and adjust the axial test pressure, repeat steps 2 and 3; Step 5: Calculate the axial force along the proximal fixing axis based on the detection value of the contact force and the detection angle; Step 6: Under different detection angles, fit the correspondence between the calculated axial force and the change in the proximal-distal distance based on the calculated axial force and the change in the proximal-distal distance.

[0024] In some embodiments, the basket catheter calibration method further includes a verification step: maintaining a detection angle between the axis of the proximal fixation seat of the basket electrode assembly and the detection surface of the pressure detection device; applying an axial test pressure to the basket electrode assembly along the axis of the proximal fixation seat, causing the basket electrode assembly to abut against the detection surface of the pressure detection device; applying a fixing force value to the detection surface; detecting the change in proximal-to-distal distance between the proximal and distal fixation seats of the basket electrode assembly; substituting the change in proximal-to-distal distance into the fitted correspondence to calculate the corresponding axial force mapping value; and then calculating the abutment force mapping value between the basket electrode assembly and the target tissue based on the detection angle; comparing the abutment force mapping value with the abutment force detection value detected by the pressure detection device to calculate the mapping error; and if the mapping error is within a set allowable range, storing the fitted correspondence in a processing device. Attached Figure Description

[0025] Figure 1 is a schematic diagram of a structural embodiment of the basket-shaped catheter in this application;

[0026] Figure 2 is a schematic diagram of the structure of the basket electrode assembly in Figure 1;

[0027] Figure 3 is a cross-sectional view AA of Figure 2;

[0028] Figure 4 is a magnified view of a portion of Figure 3;

[0029] Figure 5 is a top view of Figure 2;

[0030] Figure 6 is a perspective view of another embodiment of the basket electrode assembly;

[0031] Figure 7 is a frontal projection view of Figure 6;

[0032] Figure 8 is a cross-sectional view of Figure 7;

[0033] Figure 9 is a structural schematic diagram of an embodiment of the net basket conduit system in this application;

[0034] Figure 10 is a cross-sectional view of the basket electrode assembly in Figure 9;

[0035] Figure 11 is a partial enlarged view of Figure 10;

[0036] Figure 12 is a schematic diagram of the structure at the proximal fixing seat of the basket electrode assembly;

[0037] Figure 13 is a schematic diagram of the basket electrode assembly being attached to the target tissue along the axial direction.

[0038] Figure 14 is a schematic diagram of the basket electrode assembly tilted against the target tissue;

[0039] Figure 15 is a schematic diagram showing the relationship between the change in the near-far end spacing of the basket electrode assembly and the contact force.

[0040] Figure 16 is a schematic diagram showing the relationship between the change in the near-far end spacing of the basket electrode assembly and the axial force;

[0041] Figure 17 is a schematic diagram of the same near-far end spacing variation of the net basket electrode assembly but different contact angles.

[0042] Figure 18 is a schematic diagram of the structure of the basket electrode assembly in some embodiments;

[0043] Figure 19 is a structural schematic diagram of the basket electrode assembly from another perspective in some embodiments;

[0044] Figure 20 is a schematic diagram of the electrode tangent circles in some embodiments;

[0045] Figure 21 is a schematic diagram showing the position of each spline in the basket electrode assembly in some embodiments;

[0046] Figure 22 is a schematic diagram of the positions of two adjacent splines after unfolding in some embodiments;

[0047] Figure 23 is a schematic diagram comparing the electric fields formed by ablation electrodes with different structures in some embodiments (the diameter of the electric field lines in the figure is in mm);

[0048] Figure 24 is a schematic diagram of the spline structure in some other embodiments;

[0049] Figure 25 is a schematic diagram of the positions of two adjacent splines after unfolding in some other embodiments;

[0050] Figure 26 shows a pulsed electric field simulation diagram imported from the 3D model of the ablation catheter in some embodiments, where the diagram shows the range of electric field intensity of 400V / cm formed by the catheter, i.e. the effective ablation range.

[0051] Figure 27 shows the effective ablation area of ​​the basket electrode assembly at the interface between the myocardium and blood.

[0052] Figure 28 shows the pulsed electric field intensity distribution in the simulated basket electrode assembly in some embodiments;

[0053] Figure 29 shows the current density distribution on the basket electrode assembly during simulation in some embodiments.

[0054] List of feature names corresponding to the reference numerals in the figure: 100, Operating handle; 200, Tube body; 300, Basket electrode assembly; 310, Spline; 311, Elastic support; 312, Flexible circuit board; 3121, Insulating substrate; 3122, Electrode; 320, Proximal fixing seat; 321, Support component; 330, Distal fixing seat; 331, Mounting cavity; 332, Through channel; 3321, First step section; 3322, Second step section; 340, End cap; 350, Functional component; 351, Proximal position sensor; 352, Distal position sensor; 360, Seat lead wire; 361, Sheath tube; 362, Elastic skeleton; 363, Transmission line; 364, Elastic telescopic section; 365, Straight section; 400, Target tissue; 500, Processing device; 1, Basket skeleton; 11. Spline; 111. Elastic deformation section; 1111. First elastic section; 1112. Second elastic section; 1113. Electrode fixing section; 1114. Connecting section; 1115. Hole; 11151. First hole; 11152. Second hole; 11153. Third hole; 1116. Notch; 1117. Cantilever; 112. Proximal fixing section; 113. Distal fixing section; 12. Proximal side; 13. Distal side; 14. Boundary; 2. Ablation electrode; 21. First electrode; 22. Second electrode; 23. Outer surface of electrode; 231. Middle part; 232. Side; 5. Electrode tangent circle; 6. Flexible circuit board.

[0055] Explanation of reference numerals in parentheses in the accompanying drawings: The feature referred to by the reference numerals in parentheses in the accompanying drawings is the feature represented by both the number inside the parentheses and the number outside the parentheses. Detailed Implementation

[0056] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments. Similar elements in different embodiments are referred to by related similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of the present application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to the present application are not shown or described in the specification. This is to avoid obscuring the core parts of the present application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0057] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can be rearranged or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the specification and drawings are only for the clear description of a particular embodiment and do not imply a necessary order, unless otherwise stated that a particular order must be followed.

[0058] The serial numbers assigned to components in this document, such as "first" and "second," are used only to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages).

[0059] Please refer to the embodiments shown in Figures 1 to 8. In some embodiments of the basket-shaped conduit, a seat lead wire is provided on the distal fixing seat of the basket electrode assembly. The seat lead wire includes an elastic telescopic section. The elastic telescopic section can change its size along the proximal-distal direction as the position of the distal fixing seat changes. When the basket electrode assembly expands and contracts, the seat lead wire can extend freely without affecting the connection of the seat lead wire. Compared with routing through splines, this helps to reduce the processing difficulty of the basket electrode assembly.

[0060] Please refer to Figure 1. In some embodiments, the basket-shaped catheter includes an operating handle 100, a tube body 200, and a basket electrode assembly 300, which are connected sequentially from the proximal end to the distal end of the electrophysiological catheter.

[0061] Those skilled in the art should understand that the terms "proximal" and "distal" used in this document are conventional medical terms. For the instrument to be operated, the proximal end is the end closer to the operator, and the distal end is the end farther from the operator, and is usually the end that first enters the patient's body; the proximal and distal ends can be referred to in the figures for their orientation. Correspondingly, the proximal-distal direction refers to the distribution direction of the proximal and distal ends of the corresponding components, while the circumferential direction refers to the direction in which the corresponding components revolve around the axis of the proximal-distal direction.

[0062] The operating handle 100 allows the operator to grip and perform corresponding operations. Its specific operating functions can be designed as needed, such as for adjusting the bending section at the distal end of the basket-shaped conduit. The tube body 200 is connected to the distal end of the operating handle 100. The operating handle 100 and the tube body 200 can drive the basket electrode assembly 300 to move. The tube body 200 can also provide a substrate for laying out corresponding circuits and / or fluid circuits, allowing the corresponding circuits and / or fluid circuits to be connected to the basket electrode assembly from the operating handle 100.

[0063] Please refer to Figures 2 to 3 and Figure 5. The basket electrode assembly 300 includes a spline 310, a proximal fixing base 320, and a distal fixing base 330. The specific structure of the basket electrode assembly 300 is described below.

[0064] The splines 310 of the basket electrode assembly 300 are distributed circumferentially around the basket electrode assembly 300, and the number can be set as needed. For example, in the illustrated embodiment, there are 6 splines 310. In some embodiments, each spline 310 is a curved structure in the free state, so that the basket electrode assembly 300 is in an expanded shape in the free state, such as a spherical shape. It should be noted that the curved structure of the spline 310 means that at least a part of the spline 310 is curved, and the specific shape can be determined according to the required expansion shape of the basket electrode assembly 300. The splines 310 adopt this structural form, making the basket electrode assembly a self-expanding basket electrode assembly. When the basket electrode assembly 300 is retracted into the sheath, the sheath compresses the splines 310, causing the splines 310 to gradually undergo elastic deformation and straighten, and the basket electrode assembly 300 retracts into a tubular shape; when the basket electrode assembly 300 comes out from the sheath opening at the distal end of the sheath, the splines 310 gradually return to their curved shape, and the basket electrode assembly 300 can expand and spring back into an expanded shape on its own.

[0065] In some embodiments, referring to FIG2, the spline 310 may include an elastic support 311 and an electrode 3122. In one specific embodiment, the spline 310 includes a flexible circuit board 312 for setting the electrode 3122, and the self-expansion and spring-opening force of the basket electrode assembly 300 can be achieved by the elastic support 311. The elastic support 311 is elastic and, in some embodiments, may be made of an elastic metal, such as a nickel-titanium alloy. Nickel-titanium alloy is a shape memory alloy with good biocompatibility and can rebound well to its initial shape after being deformed by external force. The elastic support 311 may be an elastic sheet with a sheet-like structure. Of course, in some other embodiments, the elastic support 311 may also be made of other materials, such as non-metallic materials. In some other embodiments, the spline 310 may also be replaced with other structural forms. For example, the elastic support 311 may also be a columnar skeleton, and the electrode 3122 may be an annular electrode arranged around the elastic support 311.

[0066] In one specific embodiment, the flexible circuit board 312 may include an insulating substrate 3121 and electrodes 3122 for transmitting electrical energy. Those skilled in the art will understand that the insulating substrate 3121 may be made of polyimide (PI), polyethylene terephthalate (PET), etc., while the electrodes 3122 may be made of platinum-iridium alloy, stainless steel alloy, gold, copper, etc., and the surface of the electrodes 3122 may be coated to meet corresponding functional requirements. The bonding method of the electrodes 3122 to the insulating substrate 3121 is not limited; for example, they may be bonded to the insulating substrate 3121 by means of bonding, etching, plating, etc. The electrodes 3122 have exposed discharge surfaces and can form an electric field during use. In this application, the number, shape, size, and distribution position of the electrodes 3122 on a single spline 310 are not limited, and those skilled in the art can design them as needed. In some embodiments, the flexible circuit board 312 may also include a cover layer, the material of which may be the same as that of the insulating substrate 3121, and which may be bonded to the insulating substrate 3121 by means of bonding, hot pressing or other methods, thereby providing protection for the circuit on the insulating substrate 3121.

[0067] The flexible circuit board 312 is fixed to the elastic bracket 311 and bends and deforms with the elastic bracket 311. The fixing method between the flexible circuit board 312 and the elastic bracket 311 is not limited. For example, in some embodiments, it can be fixed by adhesive, such as polyurethane glue, UV glue, epoxy resin, acrylic resin, etc.; in other embodiments, the flexible circuit board 312 can also be fixed to the elastic bracket 311 by hot pressing. Those skilled in the art should know that the specific method of fixing the flexible circuit board 312 to the elastic bracket 311 of the basket electrode assembly 300 by hot pressing can refer to existing processes in related technologies. By applying a certain temperature and pressure, the adhesive or coating between the material to be fixed (such as the flexible circuit board 312) and the substrate (such as the elastic bracket 311) softens and flows, filling the tiny gaps between them, thereby creating a tight contact and bond. Considering that this is not directly related to the innovative content and technical problem to be solved in this application, it will not be described in detail here. Using hot pressing is beneficial for achieving strong bonding strength and high production efficiency.

[0068] The proximal retainer 320 of the basket electrode assembly 300 provides a proximal fixed connection for the spline 310. During the manufacture of the basket-shaped conduit, the proximal retainer 320 can be fixed to the tube body 200 of the basket-shaped conduit, thereby connecting the basket electrode assembly 300 to the tube body 200. In some embodiments, the proximal retainer 320 may include a section of tube, and the proximal end of the spline 310 can be fixed to the inner wall of the tube body. Those skilled in the art will understand that in some other embodiments, the proximal retainer 320 can be replaced with other structures, not limited to a hollow tube body, as long as it meets the fixing requirements of the proximal end of the spline 310 and other requirements of the basket-shaped conduit.

[0069] The distal end retainer 330 of the basket electrode assembly 300 provides a fixed connection for the distal end of the spline 310. For example, as shown in Figure 3, the distal end of the spline 310 can be bent and inserted into the mounting cavity 331 of the proximal end retainer 320 for fixation. The distal end retainer 330 is movable relative to the proximal end retainer 320 along the proximal-distal direction of the basket electrode assembly 300. In some embodiments, the distal end retainer 330 can fix the distal ends of the independent splines 310 together, giving the basket electrode assembly 300 a controllable shape. In some other embodiments, each spline 310 can also be formed from strip-shaped portions of an integral structure.

[0070] For basket-shaped catheters, it is necessary to determine the position of the basket electrode assembly 300 within the patient's body and / or to perform some probing within the patient's body during use. Therefore, in some embodiments, the basket electrode assembly 300 may also include functional components 350 disposed on the distal fixation base 330. These functional components 350 may be electronic components, such as magnetic field-based position sensors, which can sense information such as the spatial position and / or angle of the basket electrode assembly 300. In some other embodiments, the functional components 350 may also be other components, such as an ultrasound module, a ranging module, a visual imaging module, a pressure sensor, etc. The ultrasound module is used to perform ultrasound detection on the target tissue, the ranging module is used to detect the distance between the distal end of the basket electrode assembly 300 and the target tissue, the visual imaging module is used to image the surrounding environment of the distal end of the basket electrode assembly 300, and the pressure sensor is used to detect the adhesion force between the basket electrode assembly 300 and the target tissue.

[0071] The distal mounting base 330 can be a rotating structure, facilitating manufacturing and achieving uniformity in all directions of the basket electrode assembly 300. To facilitate the mounting of the functional component 350, in some embodiments, referring to FIG4, the distal mounting base 330 has a mounting cavity 331. The mounting cavity 331 forms an opening on the distal mounting base 330 for mounting the functional component 350, for example, an opening formed on the distal end face of the distal mounting base 330. The functional component 350 can be fixed within the mounting cavity 331. The basket electrode assembly 300 may also include an end cap 340, which can be fixed to the distal opening of the distal mounting base 330. In some other embodiments, the opening for accommodating the functional component 350 may also be located at other locations on the distal mounting base 330, such as the proximal end face or outer peripheral surface. Additionally, the functional component 350 may also be located outside the distal mounting base 330.

[0072] For the basket electrode assembly 300 with functional component 350, since functional component 350 often needs to be connected to lead wires, and the basket electrode assembly 300 is a self-expanding structure, the tube body 200 of the basket-shaped conduit does not have a drive rod for driving the movement of the distal fixing seat. Therefore, the lead wire cannot be led out from the drive rod. In order to facilitate the free extension of the lead wire of functional component 350 when the basket-shaped conduit expands and retracts, in some cases, the lead wire is often led out through spline 310. However, in this case, the lead wire needs to be fixed to spline 310, which increases the manufacturing difficulty of spline 310 and basket electrode assembly 300.

[0073] In embodiments of this application, to avoid increasing the manufacturing difficulty of the spline 310 and the basket electrode assembly 300 by fixing the lead wire to the spline 310, the basket electrode assembly 300 further includes a base lead wire 360. In one specific embodiment, the base lead wire 360 ​​may include an elastic telescopic section 364, at least a portion of which is located between the proximal fixing seat 320 and the distal fixing seat 330. The elastic telescopic section 364 is used to change its size along the proximal-distal direction as the position of the distal fixing seat 330 changes, thereby avoiding setting the lead wire on the spline 310 while meeting the lead wire lead wire lead wire lead wire requirements. The elastic telescopic section 364 may be only located between the proximal fixing seat 320 and the distal fixing seat 330, or a portion may be located between the proximal fixing seat 320 and the distal fixing seat 330, and another portion may be located within the proximal fixing seat 320 or the distal fixing seat 330. The lead wire 360 ​​may also include a straight section 365. At least one of the proximal and distal ends of the elastic telescopic section 364 may be connected to the straight section 365. The straight section 365 at the proximal end of the elastic telescopic section 364 may be connected to the proximal fixing seat 320, and the straight section 365 at the distal end of the elastic telescopic section 364 may be connected to the distal fixing seat 330.

[0074] Referring to Figure 3, in some embodiments, the distal end of the seat lead 360 is connected to the distal fixing seat 330, and the seat lead 360 passes through the proximal fixing seat 320. In one specific embodiment, a through channel 332 is provided on the bottom wall of the mounting cavity 331 of the distal fixing seat 330, through which the lead 332 passes to connect with the functional component 350. It should be noted that although this specification specifies that the distal end of the seat lead 360 is connected to the distal fixing seat 330, in the case where the functional component 350 is provided, the seat lead 360 is actually ultimately connected to the functional component 350. Furthermore, the seat lead 360 can have a direct connection with the distal fixing seat 330, or it can be indirectly connected to the distal fixing seat 330 through the functional component 350.

[0075] The elastic telescopic function of the elastic telescopic segment 364 is achieved through its elastic telescopic structure. In some embodiments, the elastic telescopic structure of the elastic telescopic segment 364 can be a spiral structure. When the proximal and distal ends of the elastic telescopic segment 364 are stretched, the spiral structure undergoes elastic deformation, increasing the pitch. When the tension changes, the pitch changes accordingly, thereby achieving a positional change in the distal fixing seat 330. In one specific embodiment, the elastic telescopic segment 364 can be a circular spiral structure, that is, a spiral structure that appears circular when viewed along the axis of the elastic telescopic segment 364, which is relatively easy to manufacture. Those skilled in the art will understand that in some other embodiments, the elastic telescopic segment 364 can also be a spiral structure of other shapes, such as square, rectangular, or elliptical. In addition, in some other embodiments, the elastic telescopic segment 364 can also adopt other structural forms to achieve elastic telescopicity, such as a wavy zigzag structure.

[0076] In one specific embodiment, referring to Figure 4, the lead wire 360 ​​of the base includes a sheath tube 361, an elastic skeleton 362, and a transmission line 363. The elastic skeleton 362 and the transmission line 363 pass through the cavity of the sheath tube 361. The elastic skeleton 362 is used to realize the elastic expansion and contraction of the elastic telescopic section 364. For example, the sheath tube 361 can be made of polyurethane (PU), polytetrafluoroethylene (PTFE), nylon (PA), etc. The sheath tube 361 can protect the elastic skeleton 362 and the transmission line 363, which helps to prevent the elastic skeleton 362 and the transmission line 363 from being exposed to liquid environments, such as blood, and also helps to prevent damage to the transmission line 363. Furthermore, the elastic skeleton 362 and the transmission line 363 are both disposed inside the sheath tube 361, and the sheath tube 361 and the elastic skeleton 362 are fixed to the distal fixing seat 330, which helps to prevent the transmission line 363 from being directly stressed, and the structure is relatively neat, making it less likely to interfere with the spline 310. To prevent electromagnetic interference from metal, the flexible frame 362 can be made of non-metallic materials, such as plastic.

[0077] In some embodiments, the inner diameter of the sheath 361 may be larger than the inner diameter of the elastic skeleton 362, and the gap formed between the sheath 361 and the elastic skeleton 362 facilitates the arrangement of the transmission line 363. The arrangement of the transmission line 363 within the sheath 361 is not limited; for example, it may be arranged side-by-side with the elastic skeleton 362 or wound around the elastic skeleton 362. In some embodiments, the outer contour of the cross-section of the base lead-out line 360 ​​may be circular. For the base lead-out line 360 ​​with the sheath 361, the cross-section of the sheath 361 may be circular.

[0078] The aforementioned elastic frame 362 can be made of metal or non-metal, such as stainless steel or nickel-titanium alloy. The aforementioned transmission line 363 can be enameled wire or an insulated conductor.

[0079] It should be noted that in some other embodiments, the specific structure of the elastic telescopic section 364 of the base lead 360 can also be replaced with other forms. For example, referring to Figures 6 to 8, the transmission line 363 itself can be made into an elastic telescopic structure; or, the above-mentioned sheath tube 361 can be omitted.

[0080] To facilitate the connection between the sheath tube 361 and the elastic skeleton 362 and the distal fixing seat 330, in some embodiments, the through channel 332 on the distal fixing seat 330 for the lead wire of the functional component 350 to pass through is a stepped hole structure, including a first stepped segment 3321 and a second stepped segment 3322 arranged sequentially from the proximal end to the distal end of the distal fixing seat 330. The inner diameters of the first stepped segment 3321 and the second stepped segment 3322 gradually decrease. The first stepped segment 3321 is used for the distal end of the sheath tube 361 to be inserted and fixed, and the second stepped segment 3322 is used for the straight portion of the distal end of the elastic skeleton 362 to be inserted and fixed. The connection method between the sheath tube 361 and the elastic skeleton 362 and the distal fixing seat 330 is not limited, for example, it can be adhesive bonding, interference fit, or welding. The first step 3321 and the second step 3322 are provided to ensure the reliability of the connection between the sheath tube 361 and the elastic skeleton 362 and the distal fixing seat 330. In some other embodiments, the sheath tube 361 and the elastic skeleton 362 can also be fixed to the distal fixing seat 330 in other ways, such as by mating to the proximal end face of the distal fixing seat 330.

[0081] For the self-expanding basket electrode assembly 300, the basket electrode assembly 300 is in an expanded state in its free state. When it enters the sheath, it is compressed and contracts, and the distal fixing seat 330 moves towards the distal end of the basket electrode assembly 300. To avoid the elastic telescopic section 364 affecting the expanded state of the basket electrode assembly 300 in its free state, in some embodiments, when the basket electrode assembly 300 is in its expanded state, the elastic telescopic section 364 is in a free state, that is, the axial dimension of the elastic telescopic section 364 is its original dimension. This arrangement of the elastic telescopic section 364 can avoid affecting the expanded state of the basket electrode assembly 300, allowing for greater freedom of movement of the entire basket at the head end. In some other embodiments, when the basket electrode assembly 300 is in its expanded state, the elastic telescopic section 364 may also have an elastic deformation.

[0082] The lead wire 360 ​​is disposed within the internal space of the basket electrode assembly 300 and passes through the proximal fixing seat 320, thus allowing direct access to the tube body 200. In one specific embodiment, the portion of the lead wire 360 ​​passing through the proximal fixing seat 320 can be fixedly connected to the proximal fixing seat 320. This helps ensure the consistency of the elastic telescopic section's movement, thereby avoiding any impact on the shape of the basket electrode assembly in its expanded state. The method of fixing the lead wire 360 ​​to the proximal fixing seat 320 is not limited. For example, glue can be injected into the proximal fixing seat 320, and after the glue cures, the lead wire 360 ​​can be fixed to the proximal fixing seat 320. In some other embodiments, the lead wire 360 ​​can also be fixed to the tube body 200 or to a circuit board within the operating handle 100. In some embodiments, the sheath tube 361 and the elastic skeleton 362 may be located only between the proximal fixation seat 320 and the distal fixation seat 330, which helps to avoid occupying space within the tube body 200, thereby enabling the tube body 200 to achieve a smaller outer diameter.

[0083] As the basket electrode assembly 300 is pulled into the sheath by the tube body 200, it contracts under radial compression. The distal fixing seat 330 moves towards the distal end of the basket electrode assembly 300 relative to the proximal fixing seat 320. Simultaneously, the distal end of the elastic telescopic section 364 moves towards the distal end of the basket electrode assembly 300 under the pull of the distal fixing seat 330, undergoing elastic tensile deformation. As the basket electrode assembly 300 is pushed out of the sheath by the tube body 200, it gradually expands automatically into an expanded state. Under the rebound force of the elastic telescopic section 364 and the spline 310, the distal fixing seat 330 moves towards the proximal end of the basket electrode assembly 300. The elastic telescopic section 364, through its own elongation and retraction, can adapt to the positional changes of the distal fixing seat 330 relative to the proximal fixing seat 320 and ensure the continuity of the lead wire.

[0084] It should be noted that the basket-shaped catheter in the embodiments of this application can be an ablation catheter used to ablate the target tissue, such as pulsed electric field ablation (PFA) or radiofrequency ablation (RF); in addition, in some other embodiments, the basket-shaped catheter in the embodiments of this application can be a mapping catheter used to collect electrophysiological signals of the target tissue.

[0085] In some other embodiments, the base lead 360 can be a conductive wire or a fluid conduit. When the base lead 360 is a conductive wire, it can be used to lead out the conductor of the electrode 3122 on the spline 310, regardless of whether the functional component 350 is provided.

[0086] Some embodiments of the net basket electrode assembly in this application:

[0087] The basket electrode assembly can be the basket electrode assembly 300 in any of the above-described basket-shaped conduits, including a spline 310, a proximal fixation seat 320, a distal fixation seat 330, and a seat lead wire 360. The specific structure will not be described again here.

[0088] The following will describe some embodiments of the basket conduit system with reference to Figures 9 to 17.

[0089] Please refer to Figure 9. The basket-shaped catheter system includes a processing device 500 and the aforementioned basket-shaped catheter. Those skilled in the art will understand that the processing device 500 can supply power to the electrodes 3122 of the basket electrode assembly 300 to ablate the target tissue 400 and monitor the contact between the basket electrode assembly 300 and the target tissue 400.

[0090] When an electrophysiological catheter is applied to the target tissue, for balloon catheters, the elastic modulus of the tip electrode assembly is relatively consistent in all directions under the same degree of inflation. This means that the force applied to the tip electrode assembly at various angles will cause the same relative positional changes between the proximal and distal ends. However, for basket-shaped catheters, the tip electrode assembly is a basket electrode assembly. The supporting component of the basket electrode assembly is a spline arranged around the axis of the tip electrode assembly, with electrodes for transmitting electrical energy distributed on the spline. Since there are gaps between the splines, the deformation capacity of different parts of the proximal and distal ends of each spline is different. When different parts of the spline are subjected to force, the basket electrode assembly will exhibit different morphological changes. Therefore, the application force of basket-shaped catheters cannot be detected using the aforementioned balloon catheter application force detection method.

[0091] In some embodiments of the basket catheter system of this application, the processing device connected to the basket catheter utilizes the correlation between the axial force value of the basket electrode assembly and the change in the proximal-distal distance ΔX, as well as the conversion relationship between the contact angle between the basket electrode assembly and the target tissue and the axial force value. The change in the proximal-distal distance ΔX of the basket catheter can be obtained through the proximal position sensor and the distal position sensor, thereby obtaining the contact force between the basket electrode assembly and the target tissue, and realizing the detection of the contact force between the basket catheter and the target tissue.

[0092] For the ablation catheter, the processing device 500 can be formed by the ablation host, which has a display module, an electrical module for supplying power to the basket-shaped catheter, etc., and may include the aforementioned processing device 500.

[0093] Of course, in some other embodiments, the processing device 500 described above can exist independently of the ablation host and be used only for detecting the contact force of the basket electrode assembly 300. Furthermore, since magnetic positioning sensors are already a component of many existing three-dimensional mapping systems, a three-dimensional mapping system can also be used as the processing device 500 to achieve contact force detection.

[0094] Referring to Figure 10, the basket electrode assembly 300 includes splines 310, a proximal fixing seat 320, and a distal fixing seat 330. The splines 310 are distributed circumferentially around the basket electrode assembly 300 and are elastically deformable. The proximal fixing seat 320 is connected to the proximal end of each spline 310, and the distal fixing seat 330 is connected to the distal end of each spline 310. The basket electrode assembly 300 also includes a proximal position sensor 351 and a distal position sensor 352 respectively disposed on the proximal fixing seat 320 and the distal fixing seat 330. The proximal position sensor 351 and the distal position sensor 352 can sense information such as the spatial position and / or angle of the basket electrode assembly 300. For example, by calculating the change in the proximal-distal distance ΔX of the basket electrode assembly based on the spatial position of the proximal position sensor 351 and the distal position sensor 352, the change in the proximal-distal distance of the basket electrode assembly can be obtained. Referring to Figure 13, the proximal-distal distance X can be the straight-line distance between the distal end of the proximal fixation seat 320 and the proximal end of the distal fixation seat 330. Alternatively, the distance between other points on the distal fixation seat 330 and the proximal fixation seat 320 can also be defined as the proximal-distal distance. When the basket electrode assembly 300 is in contact with the target tissue 400, it deforms. The distal position sensor 352 moves relative to the proximal position sensor 351 along with the distal fixation seat 330. The change in the proximal-distal distance ΔX of the basket electrode assembly can be detected by the position signals output by the proximal position sensor 351 and the distal position sensor 352.

[0095] It should be noted that although the positioning centers of the aforementioned near-end position sensor 351 and far-end position sensor 352 can generally be the center position of the magnetic sensor axis, in reality, regardless of which two points on the near-end position sensor 351 and far-end position sensor 352 the distance between is defined as, since the change in the near-end and far-end distance ΔX is a relative value, i.e., |real-time distance - reference distance|, it does not affect the calculation of the change in the far-end distance ΔX.

[0096] In some embodiments, both the near-end position sensor 351 and the far-end position sensor 352 can be 5DOF magnetic sensors. The specific structure of the magnetic sensor can refer to the existing structure in the related art and can be in the form of a coil. Considering that its specific structure is not directly related to the innovative content of this application and the technical problem to be solved, it will not be described in detail here.

[0097] Of course, in some other embodiments, the proximal position sensor 351 and the distal position sensor 352 can also be replaced with other forms, as long as they can acquire the proximal-distal distance change ΔX and other parameters required for the normal operation of the basket-shaped duct. For example, they can be replaced with a 6DOF magnetic sensor. Those skilled in the art will understand that, essentially, the 6DOF magnetic positioning sensor can be packaged from two 5DOF magnetic positioning sensors at a certain angle (e.g., 15°). Compared to the 5DOF magnetic positioning sensor, the 6DOF magnetic positioning sensor can also output the angle information of rotation around the axis 301 of the basket-shaped duct.

[0098] Referring to Figure 12, the proximal mounting base 320 may include a support member 321 fixed within the tube body. The fixing method is not limited, and can include methods such as potting, interference fit, or adhesive bonding. Mounting holes may be provided on the support member 321, into which the proximal position sensor 351 can be embedded. The wires connected to the proximal position sensor 351 can extend through the tube body 200 to the operating handle 100, and then be connected to the processing device 500 via a connector on the operating handle 100.

[0099] The proximal position sensor 351 and distal position sensor 352 are connected to a processing device 500. The processing device 500 calculates the contact force between the basket electrode assembly 300 and the target tissue 400 based on the proximal-distal distance change ΔX, the known correspondence between the axial force value of the basket electrode assembly 300 and the proximal-distal distance change ΔX, and the contact angle between the basket electrode assembly 300 and the target tissue 400. In one specific embodiment, the correspondence between the axial force value of the basket electrode assembly 300 and the proximal-distal distance change ΔX can be determined by a fitted formula, facilitating calculation. In some other embodiments, the correspondence between the axial force value of the basket electrode assembly 300 and the proximal-distal distance change ΔX can also be determined in other ways, such as by a fitted curve.

[0100] It should be noted that those skilled in the art should understand that when ablation catheters of the basket-shaped type are in vivo, the method for obtaining the contact angle between the basket electrode assembly and the target tissue can be as follows: after modeling the heart using a mapping catheter, the electromagnetic positioning algorithm inherent in the basket-shaped catheter system can calculate the deformation shape of the basket, and then calculate the contact angle between the basket electrode assembly and the target tissue of the heart model based on the model. The above calculation method can refer to existing methods in related technologies, and considering that it is not directly related to the innovative content and technical problem to be solved in this application, it will not be elaborated here.

[0101] In some embodiments, the processing device 500 can first map an axial force mapping value based on the proximal-distal distance change ΔX and the known correspondence between the axial force value of the basket electrode assembly 300 and the proximal-distal distance change ΔX. Then, based on the axial force mapping value and the contact angle, the contact force between the basket electrode assembly 300 and the target tissue 400 can be calculated. For cases where the axial force mapping value is not required, the final contact force can be calculated directly based on the relationship between the axial force mapping value, the contact angle, and the contact force between the basket electrode assembly 300 and the target tissue 400.

[0102] Please refer to Figures 13 and 14. The basket-shaped catheter may be perpendicular to the target tissue 400 along the axial direction as shown in Figure 13, or it may be inclined to the target tissue 400 along the axial direction as shown in Figure 14. As shown in Figure 15, if the relationship between the change in proximal-distal distance ΔX and the adhesion force on the tip electrode assembly is fitted according to the balloon catheter adhesion force detection method, the numerical correlation between the change in proximal-distal distance ΔX and the adhesion force on the basket-shaped catheter is low at different adhesion angles, resulting in a large detection error. As shown in Figure 16, the basket-shaped catheter is fitted to the target tissue 400 at different angles, and the angle α (i.e., the adhesion angle) between the target tissue 400 and the axis 301 of the basket-shaped catheter is recorded. Then, the axial component of the basket force is calculated using the angle α and the adhesion force. The relationship between the change in distance between the proximal position sensor 351 and the distal position sensor 352 and the axial component of the adhesion force is fitted. The fitting results show that the correlation between these two variables is significant. Therefore, the corresponding relationship can be stored in the processing device 500 for later retrieval. When invoked, the processing device calculates the change in proximal-distal distance ΔX and the axial force, and combines this with the fitting formula stored in the chip to provide real-time feedback on the catheter's contact status to the operator.

[0103] The following describes the method for determining the fitting relationship, which is also an embodiment of the net basket catheter calibration method in this application. The method includes the following steps:

[0104] Step 1: Make the axis 301 of the proximal fixing seat 320 of the basket electrode assembly 300 maintain a detection angle α with the detection surface of the pressure detection device;

[0105] This step can be achieved using a fixture. For example, the fixture can be fixed relative to the pressure detection device. A positioning clamp or positioning sleeve can be provided on the fixture. The proximal fixing seat 320 of the basket electrode assembly 300 is inserted into the positioning clamp or positioning sleeve and arranged coaxially with the positioning clamp or positioning sleeve. This ensures that the axis 301 of the proximal fixing seat 320 of the basket electrode assembly 300 maintains a detection angle α with the detection surface of the pressure detection device. The angle of the axis 301 of the positioning clamp or positioning sleeve relative to the detection surface of the pressure detection device is adjustable, thereby enabling detection at different detection angles α.

[0106] In addition, the pressure detection device mentioned above only needs to be able to detect the contact force value perpendicular to the detection surface, for example, an electronic balance can be used.

[0107] Step 2: Apply axial test pressure to the basket electrode assembly 300 along the axis 301 of the proximal fixing seat 320, so that the basket electrode assembly 300 is in contact with the detection surface of the pressure detection device, and apply a fixing force value to the detection surface. The pressure detection device detects the contact force value perpendicular to the detection surface.

[0108] In some embodiments, to achieve this step, a pushing device can be provided on the fixture. The pushing device can push the proximal fixing seat 320 of the basket electrode assembly 300 along the axis of the positioning clamp or positioning sleeve, thereby applying axial test pressure to the basket electrode assembly 300. The axial test pressure can be changed by adjusting the pushing amount of the pushing device.

[0109] Step 3: Record the following data: the change in near-far distance ΔX, the detected contact force value, and the detection angle α.

[0110] In one specific embodiment, during a single jacking process, for the corresponding detection angle α, when the jacking device pushes the device into place, the change in the near-far distance ΔX can be calculated using the near-end position sensor and the far-end position sensor. The pressure detection device then obtains the contact force detection value perpendicular to the detection surface. This data can be recorded in tabular form, as shown in Table 1 below.

[0111] Step four: Adjust the detection angle α, and repeat steps two and three; and adjust the axial test pressure, and repeat steps two and three.

[0112] The order of adjusting the included angle α and axial test pressure is not limited. The more adjustment groups of the included angle α and axial test pressure, the more complete the data, which is beneficial to improving the detection accuracy of the contact force.

[0113] Step 5: Based on the detected contact force value and the detection angle α, calculate the axial force along the axis 301 of the near-end fixed seat 320. The axial force value can be calculated using trigonometric functions. The calculated axial force value F... 轴 = Adhesion force detection value F 检测 *sinα, where α is shown in Figure 14.

[0114] The calculated values ​​of each axial force can be calculated uniformly after step four, or directly after step three.

[0115] Step 6: Under different detection angles α, based on the calculated axial force value and the change in the near-far end distance ΔX, fit the relationship between the calculated axial force value and the change in the near-far end distance ΔX.

[0116] Table 1

[0117] Based on the data in Table 1, the fitting curve shown in Figure 16 is obtained, and the fitting formula can be generated simultaneously: Axial force Y = 179.36X - 8.5211. The fitting formula is stored in the processing device 500. This fitting formula is also a representation of the correspondence between the axial force value of the basket electrode assembly and the change in the near-far end distance ΔX. Those skilled in the art will know that the fitting curve and fitting formula can be generated by the system based on experimental data.

[0118] To ensure the accuracy of the adhesion force test results, in some embodiments, the basket catheter calibration method further includes a step of verifying the calibration results: The axis 301 of the proximal fixation seat 320 of the basket electrode assembly 300 is kept at a detection angle α with the detection surface of the pressure detection device; axial test pressure is applied to the basket electrode assembly 300 along the axis 301 of the proximal fixation seat 320, causing the basket electrode assembly 300 to abut against the detection surface of the pressure detection device; a fixing force value is applied to the detection surface; the change in proximal-distal distance ΔX between the proximal and distal fixation seats 320 and 330 of the basket electrode assembly 300 is detected; the change in proximal-distal distance ΔX is substituted into the fitted relationship to calculate the corresponding axial force mapping value; and then, based on the detection angle α, the adhesion force mapping value between the basket electrode assembly 300 and the target tissue 400 is calculated; the adhesion force mapping value is compared with the adhesion force detection value detected by the pressure detection device, and the mapping error is calculated. If the mapping error is within the set allowable range, the fitted relationship is stored in the processing device 500.

[0119] The allowable range of error setting can be determined based on the design precision, for example, 0-3 grams.

[0120] When in use, the relevant cables between the operating handle and the processing device can be connected first, and then the signal of the position sensor and the information of the chip used to store the algorithm can be checked to see if they are complete. Before the basket-shaped catheter is used in the human body, it is first zeroed in the body. That is, the distance between the proximal position sensor 351 and the distal position sensor 352 in the basket-shaped catheter is set as the reference distance. For example, when the basket electrode assembly 300 is in a free expansion state, the distance between the proximal position sensor 351 and the distal position sensor 352 is used as the reference distance, which corresponds to a force value of zero.

[0121] When used in the human body, the change in proximal-to-distal distance ΔX is obtained through the position parameters of the proximal position sensor 351 and the distal position sensor 352. This change in proximal-to-distal distance ΔX is equal to the absolute value of the difference between the real-time distance between the proximal position sensor 351 and the distal position sensor 352 and the aforementioned reference distance. Substituting the change in proximal-to-distal distance ΔX into the fitting formula, and based on the relationship between the basket force application angle (i.e., the contact angle between the basket electrode assembly 300 and the target tissue 400), the contact force between the basket electrode assembly 300 and the target tissue 400, and the axial force value of the basket electrode assembly 300, the contact force between the basket electrode assembly 300 and the target tissue 400 is calculated. The contact force status is then fed back to the device operator to assist them in operating the basket-shaped catheter more safely and accurately.

[0122] As shown in Figure 17, even if the relative positions of the proximal position sensor 351 and the distal position sensor 352 are constant at different contact angles (i.e., the change in proximal-distal distance ΔX is constant), the resultant force on the basket-shaped guide tube is different because the elastic coefficients of the basket electrode assembly 300 vary in different directions. Therefore, if the contact angle of the basket electrode assembly 300 is ignored, multiple sets of contact forces will occur for the same proximal-distal distance. In this application, by adding the contact angle of the basket electrode assembly 300 as a variable and reprocessing the data, it was found that the correlation between the axial force value of the basket electrode assembly 300 and the change in proximal-distal distance ΔX is greatly improved and becomes significant. This allows the axial force value of the basket electrode assembly 300 and the change in proximal-distal distance ΔX to form a corresponding relationship that meets the detection requirements.

[0123] The following will describe some embodiments of the basket-shaped catheter with reference to Figures 18 to 29.

[0124] In some embodiments, the basket-shaped catheter is an ablation catheter. Addressing the problem of excessive electric field strength between ablation electrodes in current ablation catheters, which can easily lead to excessive arcing and stimulation of the patient, this application redesigns the arrangement of the ablation electrodes in the basket electrode assembly. The ablation electrodes on adjacent splines are positioned near the end of the elastic deformation segment within the spline. One spline's ablation electrode is positioned near the proximal end of the elastic deformation segment, while the other spline's ablation electrode is positioned near the distal end of the elastic deformation segment. This increases the spacing between the ablation electrodes, achieving electric field convergence while still meeting ablation requirements.

[0125] In some embodiments, referring to FIG18, the basket electrode assembly 300 includes a basket frame 1 and an ablation electrode 2. The basket frame 1 includes at least two splines 11, and the ablation electrode 2 is fixed to the splines 11. As the distal end of the spline 11 approaches and moves away from the proximal end, the basket frame 1 has an expanded state and a contracted state; that is, when the distal end of the spline 11 approaches the proximal end, the basket frame 1 is in an expanded state, and when the distal end of the spline 11 moves away from the proximal end, the basket frame 1 is in a contracted state. The spline 11 includes an elastically deformable segment 111, which is capable of elastic deformation as the distal end of the spline 11 approaches and moves away from the proximal end.

[0126] The circumferential direction of the basket frame 1 is the direction of the line connecting the proximal and distal ends of the basket frame 1. The elastic deformation segments 111 of two adjacent splines 11 along the circumferential direction of the basket frame 1 are the first elastic segment 1111 and the second elastic segment 1112, respectively.

[0127] The ablation electrode 2 on the first elastic segment 1111 is arranged close to the proximal end of the first elastic segment 1111 and far away from the distal end of the first elastic segment 1111, and the ablation electrode 2 on the second elastic segment 1112 is arranged close to the distal end of the first elastic segment 1111 and far away from the proximal end of the first elastic segment 1111. This allows the ablation electrode 2 on the first elastic segment 1111 and the ablation electrode 2 on the second elastic segment 1112 to be staggered along the circumference of the basket frame 1.

[0128] In this embodiment, the ablation electrode 2 on the first elastic segment 1111 and the ablation electrode 2 on the second elastic segment 1112 are offset circumferentially along the basket frame 1, resulting in a larger distance between them. This increased distance between the ablation electrodes 2 reduces the electric field strength, achieving electric field convergence while maintaining the ablation effect. This reduces the likelihood of arc formation and improves the problem of excessive patient stimulation caused by arc formation during discharge between electrodes in current pulse ablation catheters.

[0129] For ease of description, the ablation electrode 2 on the first elastic segment 1111 is defined as the first electrode 21, and the ablation electrode 2 on the second elastic segment 1112 is defined as the second electrode 22.

[0130] It should be noted that the first electrode 21 and the second electrode 22 are offset along the circumference of the basket frame 1, including both completely offset and partially offset cases. Complete offset means that the first electrode 21 and the second electrode 22 have no overlap in the circumference of the basket frame 1, while partial offset means that the first electrode 21 and the second electrode 22 have a partial overlap in the circumference of the basket frame 1.

[0131] The arrangement of the first electrode 21 and the second electrode 22 is further explained below. Referring to Figure 18, when the basket frame 1 is in its expanded state, the basket frame 1 is spherical in shape. Of course, the spherical shape here refers to a hollowed-out sphere, and it can refer to a standard sphere or other similar spherical shapes, such as an ellipsoid. Taking the midpoint between the proximal and distal ends of the basket frame 1 as the dividing line 14, one side is the proximal side 12 of the basket frame 1, and the other side is the distal side 13. The first electrode 21 described in this embodiment as being close to the proximal end and far from the distal end includes both the case where the entire first electrode 21 is located on the proximal side 12, and the case where most of the first electrode 21 is on the proximal side 12, while a small portion of the first electrode 21 is on the distal side 13. Similarly, the second electrode 22 described in the embodiments of this application is close to the distal end and far from the proximal end, including both the case where the entire second electrode 22 is located on the distal side 13 and the case where most of the second electrode 22 is located on the distal side 13 and a small portion of the second electrode 22 is located on the proximal side 12.

[0132] Further illustrative examples: In some embodiments, referring to Figure 18, the entire first electrode 21 is located on the proximal side 12, and the entire second electrode 22 is located on the distal side 13. This completely offsets the first electrode 21 and the second electrode 22 circumferentially in the basket frame 1, meaning there is no overlap between them. In some embodiments, a small portion of the first electrode 21 is located on the distal side 13, and a small portion of the second electrode 22 is located on the proximal side 12. This partially offsets the first electrode 21 and the second electrode 22 circumferentially in the basket frame 1, but there is some overlap between them. Of course, in some other embodiments, when a small portion of the first electrode 21 extends to the distal side 13 and the entire second electrode 22 is located on the distal side 13, the first electrode 21 and the second electrode 22 may partially overlap in the circumferential direction of the basket frame 1, i.e., the first electrode 21 and the second electrode 22 may be partially offset, or they may not overlap in the circumferential direction of the basket frame 1, i.e., the first electrode 21 and the second electrode 22 may be completely offset. Similarly, in some other embodiments, when a small portion of the second electrode 22 extends to the proximal side 12 and the entire first electrode 21 is located on the proximal side 12, the first electrode 21 and the second electrode 22 may partially overlap in the circumferential direction of the basket frame 1, i.e., the first electrode 21 and the second electrode 22 may be partially offset, or they may not overlap in the circumferential direction of the basket frame 1, i.e., the first electrode 21 and the second electrode 22 may be completely offset.

[0133] In some applications, compared to the case where the first electrode 21 and the second electrode 22 are completely offset, if the first electrode 21 and the second electrode 22 are partially offset, the volume of the basket frame 1 in the retracted state is larger, requiring a sheath with a larger inner diameter to pass through it. Alternatively, in some applications, the width of the overlapping portion of the first electrode 21 and the second electrode 22 in the circumferential direction of the basket frame 1 can be reduced, while the width of the non-overlapping portion can be increased. That is, the width of the overlapping portion of the first electrode 21 and the second electrode 22 in the circumferential direction of the basket frame 1 is smaller than the width of the non-overlapping portion. This way, compared to the case where the first electrode 21 and the second electrode 22 are completely offset, the volume of the basket frame in the retracted state will not increase.

[0134] The end described in the embodiments of this application is not limited to the end face of the part, but should be understood as including a region of a certain length. Regarding the distal end and proximal end of the spline 11 in the embodiments of this application, the distal end of the spline 11 refers to the portion of the spline 11 located at the distal end of the basket frame 1, and the proximal end of the spline 11 refers to the portion of the spline 11 located at the proximal end of the basket frame 1. In some embodiments, referring to FIG18, the spline 11 includes an elastically deformable segment 111, a proximal fixed segment 112, and a distal fixed segment 113. The proximal end of the elastically deformable segment 111 is connected to the proximal fixed segment 112, and the distal end of the elastically deformable segment 111 is connected to the distal fixed segment 113.

[0135] In some embodiments, referring to FIG18, the basket electrode assembly 300 includes a proximal fixation base 320 and a distal fixation base 330, with the proximal fixation segment 112 fixed to the proximal fixation base 320 and the distal fixation segment 113 fixed to the distal fixation base 330.

[0136] In some embodiments, the basket electrode assembly 300 is used for pulsed electric field ablation. Unlike the heat conduction method of radiofrequency ablation, pulsed electric field ablation relies on the energy of a pulsed electric field, and the ablation electrode 2 is used to generate the electric field.

[0137] It should be noted that in this embodiment, the ablation electrode 2 can generate an electric field to ablate tissue. Of course, this does not preclude the ablation electrode 2 from having other functions. For example, the ablation electrode 2 can also have mapping and stimulation functions to measure whether a certain area of ​​the tissue has abnormal electrical discharge, thereby enabling the ablation of the abnormal discharge area.

[0138] In some embodiments, referring to Figures 18 and 22, the width direction of the spline 11 is circumferential to the basket frame 1. The elastic deformation segment 111 includes an electrode fixing segment 1113 and a connecting segment 1114 connected to the electrode fixing segment 1113. The ablation electrode 2 is fixed on the electrode fixing segment 1113, and the width of the electrode fixing segment 1113 is larger than the width of the connecting segment 1114. This makes it easier for the basket frame 1 to open and close when using a larger electrode. In some embodiments, referring to Figures 18 and 22, the first electrode 21 and the second electrode 22 are completely offset, so that the electrode fixing segments 1113 on adjacent splines 11 can also be completely offset. After the basket frame 1 is closed, the electrode fixing segments 1113 on adjacent splines 11 are staggered, making the overall size smaller after closure.

[0139] Of course, in some other embodiments, the width of each segment of spline 11 may also be equal.

[0140] It should be noted that the width of spline 11 refers to the circumferential dimension of spline 11 in the basket frame 1, and the length of spline 11 refers to the dimension of spline 11 in the direction of extension.

[0141] Considering that the ablation electrode 2 needs to achieve both effective ablation and mapping functions, and the ablation catheter needs to pass through a sheath of a certain size, in some embodiments, referring to Figure 18, at least two ablation electrodes 2 are fixed on at least one electrode fixing section 1113. Specifically, in some embodiments, referring to Figure 18, the length and width dimensions of each ablation electrode 2 are the same. In some embodiments, the ablation electrodes 2 on the same elastic deformation section 111 have the same polarity during discharge.

[0142] In some embodiments, referring to Figure 18, the ablation electrodes 2 on the same elastic deformation segment 111 are connected in parallel, and the energizing state of each ablation electrode 2 can be controlled individually. Thus, depending on the application environment and needs, one or more ablation electrodes 2 can be energized simultaneously. In some embodiments, by controlling the energizing of different ablation electrodes 2 on the same electrode fixing segment 1113, the distance between the first electrode 21 and the second electrode 22 can also be adjusted. For example, two first electrodes 21 on the first elastic segment 1111 are arranged along the length direction of the first elastic segment 1111, and two second electrodes 22 on the second elastic segment 1112 are arranged along the length direction of the second elastic segment 1112. During ablation, two first electrodes 21 and two second electrodes 22 close to the boundary 14 can be energized, or two first electrodes 21 and two second electrodes 22 far from the boundary 14 can be energized.

[0143] It should be noted that the ablation electrode described in the embodiments of this application refers to a metal electrode that generates an ablation electric field, and the electrode can be an electrode sheet. In some embodiments, the ablation electrode 2 is fixed on the flexible circuit board 6 and is connected to the circuit on the flexible circuit board 6. The flexible circuit board can easily deform the spline 11 elastically. In some application scenarios, after the ablation electrode 2 is installed on the flexible circuit board 6, the outer surface of the ablation electrode 2 is covered with an adhesive layer. In some application scenarios, the outer surface of the ablation electrode 2 can be lower than the outer surface of the flexible circuit board 6. In the case where two or more ablation electrodes 2 are fixed on the same electrode fixing segment 1113 in the above embodiments, in one application scenario, all ablation electrodes 2 fixed on the same electrode fixing segment 1113 are fixed on the same flexible circuit board.

[0144] It should be noted that the accompanying drawings provided in this application only show the positions of the ablation electrode 2 and the flexible circuit board 6. Since the thickness of the flexible circuit board 6 and the ablation electrode 2 is very small, the thickness of the flexible circuit board 6 and the thickness of the ablation electrode 2 are not shown in the drawings.

[0145] In some embodiments, referring to Figures 18 and 19, the number of splines 11 is six in order to reduce the leakage points of the tissue between splines 11 during ablation, i.e., to reduce the ineffective ablation area between splines 11.

[0146] In some embodiments, the number of splines 11 can be determined based on the volume of the basket frame 1, ablation parameters, etc., and can be any number of two or more, such as two, three, four, five, seven, or eight or more. In some embodiments, the number of ablation electrodes 2 can also be increased or decreased as needed. For example, only one ablation electrode 2 can be provided on one elastic deformation segment 111. Of course, three, four, or five or more can also be provided on one elastic deformation segment 111.

[0147] Furthermore, in some embodiments, referring to FIG18, at least two ablation electrodes 2 fixed on the same electrode fixing segment 1113 are arranged along the length direction of the elastic deformation segment 111. In some other embodiments, at least two ablation electrodes 2 fixed on the same electrode fixing segment 1113 may also be arranged along the width direction of the elastic deformation segment 111.

[0148] To further converge the electric field of the ablation electrode 2, in some embodiments, referring to Figures 18 and 20, the side of the ablation electrode 2 facing away from the basket frame 1 is designated as the outer electrode surface 23, which is a smooth, outwardly bulging surface. The outer electrode surface 23 bulges outward from the basket frame 1 at its center 231 in the circumferential direction, opposite to its two side edges 232. The smooth surface allows for control of the ablation depth.

[0149] To further converge the electric field of the ablation electrode 2, in some embodiments, referring to Figures 18 and 20, the plane perpendicular to the line connecting the distal and proximal ends of the basket frame 1 is the latitudinal plane, and the line intersecting the outer surface 23 of the electrode with the latitudinal plane is the electrode intersection line. When the basket frame 1 is in an expanded state, the curvature near the end of the electrode intersection line is less than or equal to the curvature away from the end. It should be noted that the curvature near the end of the electrode intersection line described in the embodiments of this application being less than or equal to the curvature away from the end includes at least three cases:

[0150] First, the curvature near the end of the electrode intersection line is equal to the curvature away from the end, meaning the electrode intersection line is an arc.

[0151] Second, when the basket frame 1 is in an expanded state, the curvature of the electrode intersection line near the end is less than the curvature far from the end, that is, the curvature of the electrode intersection line gradually decreases from the middle to both ends.

[0152] Third, the part of the electrode intersection line is an arc, satisfying that the curvature near the end of the electrode intersection line is equal to the curvature away from the end of the electrode intersection line; the part is a curve with gradually changing curvature, satisfying that the curvature near the end of the electrode intersection line is less than the curvature away from the end of the electrode intersection line.

[0153] In some embodiments, when the basket frame 1 is in an expanded state, the circle tangent to the middle portion of the intersection lines of the electrodes on the same latitudinal plane is called the electrode tangency circle 5. When the basket frame 1 is in an expanded state, the curvature of each portion of the electrode intersection lines is greater than or equal to the curvature of the electrode tangency circle 5. In this way, both ends of the electrode intersection lines converge inward toward the basket frame 1, which makes the electric field generated by the ablation electrode 2 more convergent.

[0154] In some embodiments, referring to FIG23, for the outer surface 23 of the electrode with the same area, the electric field distribution in the middle region is similar to that in the case of a planar surface (as shown in FIG23(a)) and an outwardly bulging curved surface (as shown in FIG23(b)), mainly the electric field distribution at the edge changes.

[0155] Please refer to Figure 23. If both outer surfaces 23 of the electrodes are planar, the electric field distribution is as follows: at the edge of the outer surface 23 of the electrodes, the electric field lines are perpendicular to the outer surface 23 of the electrodes and then diffuse to the outer surfaces 23 of adjacent electrodes of different polarities, and the range of the diffused electric field is larger.

[0156] If both outer surfaces 23 of the electrodes are outwardly bulging curved surfaces, the electric field distribution is as follows: at the edges of the outer surfaces 23 of the electrodes, due to the certain curvature, the range of the electric field formed by the edges of two adjacent electrodes of different polarities will be smaller than that of the planar outer surfaces 23 of the electrodes. Therefore, the outwardly bulging curved surfaces of the outer surfaces 23 of the electrodes are conducive to the convergence of the electric field.

[0157] Specifically, in some embodiments, the electrode intersection line is an arc, and the curvature of each part on the electrode intersection line is equal.

[0158] In some other embodiments, the curvature of the electrode intersection line can gradually increase from the middle to both ends. The plane bisects the electrode fixing segment 1113 is the electrode bisector, and the two parts of the electrode intersection line, with the middle point as the boundary, are symmetrical about the electrode bisector. In some other embodiments, the curvature at the ends of the electrode intersection line is also less than the curvature of the middle part.

[0159] Furthermore, to facilitate the deformation of the spline 11, in some embodiments, the electrode fixing segment 1113 has a weakening structure that extends along the length of the spline 11. The strength of the weakening structure is less than that of the rest of the segment. Because the strength of the electrode fixing segment is weakened, it is easier to deform when the basket frame is opened or closed. Compared with the basket frame in the prior art, the electrode fixing segment in the basket frame of this application embodiment allows the electrode to better adhere to the tissue, resulting in better ablation effect and lower operational risk.

[0160] Regarding the form of the weakening structure, in some embodiments, referring to Figures 19 and 21, the weakening structure has a perforation 1115. In some other embodiments, the weakening structure may also have a thinning groove. The opening of the thinning groove may face towards or away from the ablation electrode 2.

[0161] In some embodiments, referring to Figures 19, 21, and 22, the perforated hole 1115 is an elongated hole whose extension direction is consistent with that of the elastically deformable segment 111. This elongated hole divides the electrode fixing segment 1113 into elongated structures, which is more conducive to the deformation of the electrode fixing segment 1113. In some other embodiments, in addition to elongated holes, the perforated holes 1115 can also be arranged in rows. Specifically, at least two perforated holes 1115 are arranged in rows along the extension direction of the spline 11, forming a perforated hole group; the number of perforated hole groups is at least two, and each perforated hole group is arranged along the width direction of the spline 11.

[0162] To further facilitate the deformation of the electrode fixing section 1113, in some embodiments, referring to Figures 24 and 25, the wall of the perforated hole 1115 has a notch 1116, which allows a portion of the wall of the perforated hole 1115 to form a cantilever 1117. This makes the portion of the wall of the perforated hole 1115 easier to deform, and facilitates the folding of the basket frame 1. In one embodiment, the ablation electrode 2 is disposed on the flexible circuit board 6 and is connected to the circuitry on the flexible circuit board 6, allowing the flexible circuit board 6 to easily deform the spline 11 elastically.

[0163] In some embodiments, referring to Figures 24 and 25, the notch 1116 is located at the distal end of the perforated hole 1115, and the cantilever 1117 extends along the length of the spline 11. This allows the distal end of the electrode fixing section 1113 to be more flexible, and while maintaining the perforation, the surface curvature and overall support of the basket, especially the support of the proximal end of the electrode fixing section 1113, are not sacrificed. Of course, in some other embodiments, if requirements are met, the notch 1116 may also be located at the proximal end of the perforated hole 1115, or at the middle of the perforated hole 1115.

[0164] Regarding the number of perforated holes 1115, in some embodiments, please refer to Figures 21 and 22, at least two perforated holes 1115 are arranged along the width direction of the spline 11. In some embodiments, please refer to Figures 21 and 22, the number of perforated holes 1115 is three. In some other embodiments, the number of perforated holes 1115 can be any number of one, two, four or more.

[0165] In some embodiments, referring to Figures 21 and 22, at least three perforations 1115 are designated as a first perforation 11151, a second perforation 11152, and a third perforation 11153. The second perforation 11152 is located between the first perforation 11151 and the third perforation 11153 in the width direction of the spline 11. The length direction of the perforations 1115 is consistent with the extension direction of the spline 11. The length of the second perforation 11152 is greater than the length of the first perforation 11151 and greater than the length of the third perforation 11153. The proximal ends of the first perforation 11151, the second perforation 11152, and the third perforation 11153 are aligned along the width direction of the spline 11. By extending the length of the second perforation 11152 distally, the flexibility of the distal end of the electrode fixing section 1113 can be increased.

[0166] In some embodiments, please refer to Figures 21 and 22, the number of perforations 1115 is three, and the first perforation 11151 and the third perforation 11153 are arranged symmetrically.

[0167] In some embodiments, referring to Figures 18 and 19, at least a portion of the perforated hole 1115 is positioned to be covered by the ablation electrode 2. In some embodiments, the ablation electrode 2 is an electrode sheet. In some embodiments, referring to Figures 1 to 25, when the basket electrode assembly 300 is in operation, the basket electrode assembly 300 is connected to the distal end of the tube body 200 and is inserted into the organism through a sheath along with the tube body 200. For lesions requiring ablation, the orientation of the basket electrode assembly 300 can be adjusted by controlling the bending of the tube body 200, allowing the basket electrode assembly 300 to abut against the tissue at different angles, and then pulsed electric field ablation is performed using the corresponding ablation electrode 2. Since the first electrode 21 and the second electrode 22 are arranged in a circumferentially staggered manner, during ablation, depending on the different orientations of the basket electrode assembly 300, the first electrode 21 and the second electrode 22 can be ablated individually or simultaneously, thereby obtaining a larger ablation range. When combined with pulsed electric field ablation, which has a greater ablation depth, a larger ablation lesion can be obtained, thereby improving surgical efficiency.

[0168] In some embodiments, please refer to Figures 26 to 29 for simulation of the ablation catheter: the 3D model of the basket-shaped pulse ablation catheter is imported into Workbench, and electric field simulation is started. During the simulation, myocardial tissue is directly in contact with the basket electrode assembly 300, and the surrounding environment is blood, with an ambient temperature of 37°C. Please refer to Figure 26, where a is the blood environment area, b is the interface between the blood environment and the myocardium, and c is the area where the myocardial tissue is located.

[0169] Simulation tests showed that the basket electrode assembly 300 did not generate a significant electric arc during the simulated discharge process. Furthermore, the electric field converged, energy was concentrated, and the ablation effect was optimal at the portion of the basket electrode assembly 300 directly in contact with the tissue. At 1000V, the ablation depth was 4.6mm, and the ablation width at a depth of 3mm was 10.4mm, meeting the acceptable size requirements for treating atrial fibrillation, thus satisfying both safety and effectiveness standards.

[0170] The above description uses specific examples to illustrate the embodiments of this application, which are only for the purpose of helping to understand the embodiments of this application and are not intended to limit the embodiments of this application. For those skilled in the art to which the embodiments of this application pertain, several simple deductions, modifications, or substitutions can be made based on the ideas of the embodiments of this application.

Claims

1. A basket electrode assembly characterized by, include: Splines are distributed circumferentially along the basket electrode assembly and are elastically deformable. In the free state, the splines are curved, so that the basket electrode assembly is in an expanded state in the free state. A proximal fixing seat is fixedly connected to the proximal end of each spline; A remote fixing seat is fixedly connected to the remote end of each spline.

2. The basket electrode assembly of claim 1, wherein, It also includes a base lead wire, the distal end of which is connected to the distal fixing seat, and the base lead wire passes through the proximal fixing seat; the base lead wire includes an elastic telescopic section, at least a portion of which is located between the proximal fixing seat and the distal fixing seat, and the elastic telescopic section is used to change its size along the proximal-distal direction of the basket electrode assembly as the position of the distal fixing seat changes.

3. The basket electrode assembly of claim 2, wherein, The elastic expansion segment has a spiral structure.

4. The basket electrode assembly of claim 2, wherein, The lead wire of the seat includes a sheath tube, an elastic skeleton and a transmission line. The elastic skeleton and the transmission line are inserted into the cavity of the sheath tube. The elastic skeleton is used to realize the elastic expansion and contraction of the elastic expansion section. The sheath tube and the elastic skeleton are fixed to the distal fixing seat.

5. The basket electrode assembly of claim 2, wherein, When the basket electrode assembly is in an expanded state, the elastic telescopic section is in a free state.

6. The basket electrode assembly of claim 2, wherein, The lead wire of the seat body is fixedly connected to the proximal fixation seat at the point where it passes through the proximal fixation seat.

7. The basket electrode assembly of claim 2, wherein, The cross-sectional outer contour of the lead wire of the seat body is circular.

8. The basket electrode assembly of claim 2, wherein, It includes a functional component, which is an electronic component. The functional component is fixed on the remote mounting base, and the lead wire of the mounting base is connected to the functional component to realize the circuit connection of the functional component.

9. The basket electrode assembly of claim 2, wherein, The lead wire of the base is either an electrical wire for conducting electricity or a pipeline for transporting fluid.

10. The basket electrode assembly of claim 1, wherein, It also includes a proximal position sensor and a distal position sensor respectively disposed on the proximal fixation base and the distal fixation base, the proximal position sensor and the distal position sensor being used to obtain the change in the proximal-distal distance of the basket electrode assembly.

11. The basket electrode assembly of claim 10, wherein, Both the near-end position sensor and the far-end position sensor are 5DOF magnetic sensors.

12. A basket catheter characterized by, It includes an operating handle, a tube body, and an electrode assembly connected sequentially from the proximal end to the distal end, wherein the electrode assembly is the basket electrode assembly according to any one of claims 1 to 11.

13. A basket catheter characterized by, The basket electrode assembly as described in claim 1 includes a basket skeleton, the basket skeleton includes the spline, and the spline includes at least two splines; the basket skeleton has an expanded shape and a contracted state as the distal end of the spline approaches and moves away from the proximal end; the spline includes an elastic deformation segment, which is capable of elastic deformation as the distal end of the spline approaches and moves away from the proximal end. and an ablation electrode, which is fixed on the elastic deformation segment; The elastic deformation segments of two adjacent splines along the circumferential direction of the basket electrode assembly are respectively the first elastic segment and the second elastic segment; the ablation electrode on the first elastic segment is arranged close to the proximal end and far from the distal end, and the ablation electrode on the second elastic segment is arranged close to the distal end and far from the proximal end; the ablation electrode on the first elastic segment and the ablation electrode on the second elastic segment are offset along the circumferential direction of the basket skeleton.

14. The basket catheter of claim 13, wherein, The width direction of the elastic deformation section is the circumferential direction of the basket frame. The elastic deformation section includes an electrode fixing section and a connecting section connected to the electrode fixing section. The ablation electrode is fixed on the electrode fixing section. The width dimension of the electrode fixing section is greater than the width dimension of the connecting section.

15. The basket catheter of claim 14, wherein, At least two ablation electrodes are fixed on at least one of the electrode fixing sections, and the at least two ablation electrodes fixed on the same electrode fixing section are arranged along the length direction of the elastic deformation section.

16. The basket catheter of claim 14, wherein, At least two ablation electrodes are fixed on at least one of the electrode fixing sections, and the at least two ablation electrodes fixed on the same electrode fixing section are arranged along the length direction of the elastic deformation section.

17. The basket catheter of claim 13, wherein, The side of the ablation electrode facing away from the basket frame is the outer side of the electrode, which is a smooth curved surface that bulges outward; the outer side of the electrode bulges outward from the basket frame on both sides in the middle of the circumferential direction of the basket frame.

18. The basket catheter of claim 17, wherein, The plane perpendicular to the line connecting the far end and the near end of the basket frame is the latitudinal plane, and the line where the outer surface of the electrode intersects the latitudinal plane is the electrode intersection line; when the basket frame is in the expanded state, the curvature near the end of the electrode intersection line is less than or equal to the curvature away from the end.

19. The basket catheter of claim 18, wherein, When the basket frame is in the expanded state, the circle that is tangent to the middle part of the intersection line of each electrode on the same latitudinal plane is the electrode tangency circle, and the curvature of each part on the electrode intersection line is greater than or equal to the curvature of the electrode tangency circle.

20. The basket catheter of any of claims 13-19, wherein, The electrode fixing segment includes a weakening structure for reducing the strength of the electrode fixing segment, the weakening structure extending along the length direction of the spline.

21. The basket catheter of claim 20, wherein, The weakening structure has a thinning groove, the opening of which faces the ablation electrode or faces away from the ablation electrode, or the weakening structure has a hollow hole.

22. The basket of claim 21, wherein the basket is configured to be deployed in a collapsed configuration and an expanded configuration. The hollow hole is an elongated hole extending along the extension direction of the elastic deformation segment.

23. The basket-shaped catheter of the ablation catheter as described in claim 22, characterized in that, At least one of the hollow holes has a notch in the wall at the distal end, the notch being used to allow a portion of the hollow hole wall to form a cantilever.

24. A basket catheter system characterized by, The device includes a processing unit, an operating handle, a tube body, and a basket electrode assembly connected sequentially from the proximal end to the distal end. The basket electrode assembly is the same as any one of claims 1 to 9. The basket electrode assembly further includes a proximal position sensor and a distal position sensor respectively disposed on the proximal fixation base and the distal fixation base. The proximal position sensor and the distal position sensor are used to acquire the change in the proximal-distal distance of the basket electrode assembly. The proximal position sensor and the distal position sensor are used to acquire the change in the proximal-distal distance of the basket catheter. The proximal position sensor and the distal position sensor are connected to the processing unit. The processing unit is used to obtain the contact force between the basket electrode assembly and the target tissue based on the change in the proximal-distal distance, the known correspondence between the axial force value of the basket electrode assembly and the change in the proximal-distal distance, and the contact angle between the basket electrode assembly and the target tissue.

25. The basket catheter system of claim 24, wherein, The process of the processing device calculating the contact force includes the following steps: First, based on the change in the proximal-distal distance, the known correspondence between the axial force value of the basket electrode assembly and the change in the proximal-distal distance, the axial force mapping value is obtained; then, based on the axial force mapping value and the contact angle, the contact force between the basket electrode assembly and the target tissue is calculated.

26. The basket catheter system of claim 25, wherein, The relationship between the axial force value of the basket electrode assembly and the change in the proximal-distal distance is determined by a fitting formula.

27. A method of calibrating a basket catheter, the method comprising: Includes the following steps: Step 1: Make sure the axis of the proximal fixing seat of the basket electrode assembly is at a detection angle with the detection surface of the pressure detection device; Step 2: Apply axial test pressure to the basket electrode assembly along the axis of the proximal fixing seat, so that the basket electrode assembly is in contact with the detection surface of the pressure detection device, apply a fixing force value to the detection surface, and the pressure detection device detects the contact force value perpendicular to the detection surface; Step 3, record the following data: the change in the near-far distance of the basket electrode assembly, the detected contact force value, and the detection angle; Step four: Adjust the detection angle, and repeat steps two and three; And, adjust the axial test pressure, and repeat steps two and three; Step 5: Based on the detected abutment force value and the detection angle, calculate the axial force along the axis of the near-end fixed seat. Step 6: Under different detection angles, based on the calculated axial force value and the change in the proximal-distal distance, fit the corresponding relationship between the calculated axial force value and the change in the proximal-distal distance.

28. The catheter calibration method of claim 27, wherein, The method further comprises a verification step: an angle between an axis of a proximal fixing seat of the basket electrode assembly and a detection surface of the pressure detection device is kept unchanged, an axial test pressure is applied to the basket electrode assembly along the axis of the proximal fixing seat, the basket electrode assembly is abutted against the detection surface of the pressure detection device, a fixed force value is applied to the detection surface, a proximal-distal distance change between the proximal fixing seat and the distal fixing seat of the basket electrode assembly is detected, the proximal-distal distance change is substituted into the fitted corresponding relationship, a corresponding axial force mapping value is calculated, and then an abutting force mapping value between the basket electrode assembly and the target tissue is calculated according to the angle; The abutting force mapping value is compared with an abutting force detection value detected by the pressure detection device, a mapping error is calculated, and if the mapping error is within a set allowable range, the fitted corresponding relationship is stored in the processing device.

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