Balloon catheter, catheter electrode assembly, and flexible circuit board of catheter electrode assembly

Abstract

The present application relates to the field of electrophysiology catheters, and in particular to a balloon catheter, a catheter electrode assembly, and a flexible circuit board of the catheter electrode assembly. The flexible circuit board of the catheter electrode assembly comprises: an insulating substrate, the insulating substrate being used for being attached to the surface of a balloon of the balloon catheter; an electrode sheet, the electrode sheet being fixed on the insulating substrate, and the electrode sheet being used for transmitting electrical energy; a conductive trace, the conductive trace being attached to the surface of the insulating substrate, and the conductive trace being connected to the electrode sheet to achieve electrical energy transmission; and a trace insulating layer provided corresponding to the conductive trace, the trace insulating layer covering the conductive trace, and the insulating substrate having an exposed region not covered by the trace insulating layer. The present application mainly solves the technical problems that a flexible circuit board of a catheter electrode assembly is prone to separation from a balloon, and the flexible circuit board restricts the balloon from contracting to a small diameter.

Description

Balloon catheter, catheter electrode assembly, and flexible circuit board of catheter electrode assembly Technical Field

[0001] This application relates to the field of electrophysiological catheters, specifically to balloon catheters, catheter electrode assemblies, and flexible circuit boards for catheter electrode assemblies. Background Technology

[0002] Atrial fibrillation (AF) is the most common arrhythmia in clinical practice, and its incidence gradually increases with age. Currently, catheter ablation has become an important treatment for AF. Pulsed electric field ablation is a novel tissue ablation technique based on physical energy factors that has emerged in recent years. It mainly utilizes the principle of irreversible electroporation, applying a high-voltage pulsed electric field to cells to cause irreversible perforation of the cell membrane, leading to gradual cell necrosis and ultimately achieving tissue ablation.

[0003] Pulsed electric field ablation can be achieved using a balloon catheter. An important component of the balloon catheter is the catheter electrode assembly, which includes a balloon body and a flexible circuit board fixed to the surface of the balloon body. The balloon body provides support for and positions the flexible circuit board, which is equipped with electrode pads that can be used to generate a pulsed electric field.

[0004] However, during repeated inflation and deflation of the balloon, separation can easily occur between the flexible circuit board and the balloon body. Additionally, the flexible circuit board can limit the balloon's diameter after contraction. Summary of the Invention

[0005] The main technical problem addressed by this application is that the flexible circuit board of the catheter electrode assembly is prone to separation from the capsule, and the flexible circuit board restricts the capsule from forming a smaller diameter after contraction.

[0006] In one aspect, one embodiment provides a flexible circuit board for a conduit electrode assembly.

[0007] The flexible circuit board of the catheter electrode assembly includes:

[0008] An insulating substrate, said insulating substrate being attached to the balloon surface of the balloon catheter;

[0009] Electrode plates, which are fixed on the insulating substrate, are used to transmit electrical energy;

[0010] A conductive line is attached to the surface of the insulating substrate and connected to the electrode sheet to achieve electrical energy transmission;

[0011] And a line insulation layer corresponding to the conductive line, the line insulation layer covering the conductive line, the insulating substrate having an exposed area not covered by the line insulation layer.

[0012] In one embodiment, the electrode sheet includes a first electrode sheet and a second electrode sheet, and the conductive line includes a first line and a second line, wherein the first line and the second line are respectively connected to the first electrode sheet and the second electrode sheet;

[0013] The first line is located on the side of the insulating substrate where the electrode sheet is located, and the second line is located on the side of the insulating substrate opposite to the electrode sheet. The second line is electrically connected to the first electrode sheet by means of a conductive structure passing through the insulating substrate. Both the first line and the second line extend to one end of the insulating substrate along the arrangement direction of the first and second electrode sheets.

[0014] In one embodiment, at least a portion of the first line and the second line are spaced apart in the width direction of the flexible circuit board.

[0015] In one embodiment, the flexible circuit board includes pads fixed on the insulating substrate, the pads being connected to the end of the conductive line away from the electrode sheet, and the pads being used for soldering wires to transmit electrical energy.

[0016] In one embodiment, the first pad connected to the first line and the second pad connected to the second line are located on the same surface of the insulating substrate.

[0017] In one embodiment, the flexible circuit board includes a lead-out portion disposed near the proximal end of the flexible circuit board, the lead-out portion for the conductive lines to be led out, the width of the lead-out portion being smaller than the width of the adjacent portion, and the pads being disposed on the lead-out portion.

[0018] In one embodiment, the flexible circuit board includes a proximal portion, a distal portion, and an intermediate connecting portion. The proximal portion and the distal portion are respectively disposed on the proximal side and the distal side of the capsule. The intermediate connecting portion connects the proximal portion and the distal portion, and the width of the intermediate connecting portion is smaller than the width of the proximal portion and the distal portion. The electrode includes a proximal electrode disposed on the proximal portion and a distal electrode disposed on the distal portion. The conductive line connected to the distal electrode passes through the intermediate connecting portion.

[0019] In one embodiment, the electrode sheet is attached to the surface of the insulating substrate, and the flexible circuit board includes an edge insulating layer disposed corresponding to the edge of the electrode sheet. The shape of the edge insulating layer is consistent with the shape of the edge of the electrode sheet. The edge insulating layer has an electrode covering portion and a substrate connecting portion. The electrode covering portion covers the edge surface of the electrode sheet, and the substrate connecting portion and the electrode covering portion form a stepped structure. The stepped structure is used to match the thickness of the edge of the electrode sheet, and the substrate connecting portion is connected to the insulating substrate.

[0020] Secondly, one embodiment provides a catheter electrode assembly.

[0021] The catheter electrode assembly includes:

[0022] A capsule, which can expand and contract;

[0023] And a flexible circuit board, wherein the flexible circuit board is any of the flexible circuit boards described above.

[0024] Thirdly, one implementation provides a balloon catheter.

[0025] Balloon catheters, including:

[0026] Operating handle;

[0027] An insertion tube is connected to the distal end of the operating handle;

[0028] And a catheter electrode assembly, the balloon assembly being connected to the distal end of the insertion tube, the catheter electrode assembly including a balloon body and a flexible circuit board, the balloon body being inflatable and contractible, the flexible circuit board being attached to the balloon body, the flexible circuit board being any of the flexible circuit boards described above.

[0029] The beneficial effects of this application are:

[0030] The flexible circuit board used in the catheter electrode assembly has conductive lines attached to an insulating substrate. These conductive lines enable the transfer of electrical energy to the electrode pads. Compared to using separate wires, this design is simpler and saves space. Simultaneously, the balloon catheter has an insulating layer corresponding to the conductive lines, creating exposed areas on the insulating substrate. The insulation of the conductive lines is achieved through this insulating layer, which prevents the exposed areas of the conductive lines from being exposed, thus meeting their insulation requirements. Furthermore, the insulating layer is specifically designed for the conductive lines, which helps avoid increasing the overall thickness of the flexible circuit board and preventing poor conformability due to excessive thickness. The flexible circuit board can better adapt to the expansion and contraction of the balloon, preventing excessive stress during deformation that could cause the flexible circuit board to separate from the balloon. This results in better product reliability and also facilitates shrinkage to a smaller diameter with the balloon. Attached Figure Description

[0031] Figure 1 is a schematic diagram of a structure of an embodiment of the balloon catheter in this application;

[0032] Figure 2 is a three-dimensional schematic diagram of the catheter electrode assembly in Figure 1;

[0033] Figure 3 is a front view schematic diagram of the catheter electrode assembly in Figure 1;

[0034] Figure 4 is a frontal projection of the flexible circuit board in Figure 3;

[0035] Figure 5 is a frontal projection of the back side of the flexible circuit board in Figure 4;

[0036] Figure 6 is a cross-sectional view of an embodiment of a flexible circuit board;

[0037] Figure 7 is a schematic diagram of the catheter electrode assembly in the retracted state;

[0038] Figure 8 is a perspective view of the catheter electrode assembly in another embodiment of the balloon catheter in this application.

[0039] List of feature names corresponding to the labels in the figure:

[0040] 100. Operating handle;

[0041] 200. Insert tube;

[0042] 300. Catheter electrode assembly;

[0043] 310. Cyst;

[0044] 320. Flexible circuit board;

[0045] 321, Insulating substrate; 3211, Through hole;

[0046] 322, Electrode sheet; 3221, Proximal electrode sheet; 3222, Distal electrode sheet; 3223, Coating;

[0047] 323, Conductive circuit; 3231, First circuit; 3232, Second circuit;

[0048] 324. Edge insulating layer; 3241. Electrode covering portion; 3242. Substrate connection portion;

[0049] 325. Line insulation layer;

[0050] 3261, First pad; 3262, Second pad;

[0051] 327. Via;

[0052] 3281. Proximal portion; 3282. Distal portion; 3283. Intermediate connecting portion; 3284. Lead-out portion. Detailed Implementation

[0053] 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.

[0054] 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.

[0055] 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. Unless otherwise specified, the terms "connection" and "linkage" used in this application include both direct and indirect connections (linkages).

[0056] In the embodiments of this application, the flexible circuit board of the conduit electrode assembly sets the conductive lines on the insulating substrate, and realizes the power transmission of the electrode sheet through the conductive lines. Compared with setting separate wires, the structure is simpler and can save the space occupied by the wires. At the same time, the conductive lines are insulated by the corresponding line insulation layer. Compared with covering the entire insulating layer on the insulating substrate (such as PI (Polyimide) film with the same shape and size as the insulating substrate), it is beneficial to the thinning of the flexible circuit board.

[0057] Examples of balloon catheters in this application:

[0058] Please refer to Figure 1. In one embodiment, the balloon catheter includes an operating handle 100, an insertion tube 200, and a catheter electrode assembly 300, which are connected sequentially from the proximal end to the distal end of the balloon catheter.

[0059] The operating handle 100 allows the operator to grip and perform corresponding operations. Its specific functions can be designed as needed, such as adjusting the balloon catheter's bend and controlling the inflation and contraction of the balloon. The insertion tube 200 is connected to the distal end of the operating handle 100, enabling movement of the catheter electrode assembly 300 and providing a substrate for the corresponding circuits, fluid paths, and / or gas paths, allowing these pathways to connect from the operating handle 100 to the catheter electrode assembly 300. Referring to Figures 2 and 3, the catheter electrode assembly 300 includes a balloon 310 and electrode pads 322. The balloon 310 is inflatable and deflate. The electrode pads 322 are disposed on the surface of the balloon 310 and can inflate and contract with the balloon 310. When inflated, they can contact the target tissue to transfer electrical energy, such as contacting the myocardium causing atrial fibrillation.

[0060] 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, which is usually the end that first enters the patient's body. The proximal and distal ends can be referred to in the diagram 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 surround the axis corresponding to the proximal-distal direction.

[0061] In addition, those skilled in the art should know that the capsule 310 of the catheter electrode assembly 300 in this application can be made of polymer materials such as nylon (PA), block polyetheramide (PEBAX), polyethylene terephthalate (PET), and polyurethane (PU), and is flexible, capable of being filled with liquid or gas and contracting when the liquid or gas is discharged; when the capsule 310 is filled, it can generate tension and form a corresponding shape, such as spherical, ellipsoidal or other desired shape; when the capsule 310 contracts, the catheter electrode assembly 300 transforms into a cylindrical structure, which facilitates entry and exit from the sheath.

[0062] Electrode sheets 322 can be located on flexible circuit boards 320. Flexible circuit boards 320 include an insulating substrate 321 and electrode sheets 322. The insulating substrate 321 is attached to the capsule 310, and the electrode sheets 322 are fixed to the insulating substrate 321. The number of flexible circuit boards 320 can be set as needed. For example, in Figure 2, the capsule 310 has four flexible circuit boards 320, each of which is strip-shaped, forming a circuit strip. The flexible circuit boards 320 are distributed circumferentially along the capsule 310, and the electrode sheets 322 on each flexible circuit board 320 form a group. Alternatively, in Figure 8, the capsule 310 has six flexible circuit boards 320. The flexible circuit boards 320 can be fixed by methods such as bonding or hot pressing, and can deform with the deformation of the capsule 310 to present the desired shape for contact with the target tissue. When the capsule 310 reaches its full state, it has a large outer surface area, which allows it to support electrodes with a large area. Those skilled in the art will understand that the insulating substrate 321 can be made of common materials in the field of flexible circuit boards, such as PI and PET; in addition, the insulating substrate 321 can be a single-layer structure or a structure with two or more layers; while the electrode sheet 322 can be made of copper, silver, etc., and can be provided with a plating layer 3223 (see Figure 6), such as a gold plating layer. Of course, the plating layer 3223 is not a necessary structure.

[0063] In some cases, the balloon catheter may also include a central rod that passes through the insertion tube 200 and enters the balloon body 310. The distal end of the catheter electrode assembly 300 is fixedly connected to the central rod, which is used to move along the insertion tube 200 to adjust the position of the distal end of the balloon body 310. For example, pushing the central rod distally can increase the axial (i.e., proximal-distal) dimension of the balloon body 310, while moving the central rod proximally can decrease the axial dimension of the balloon body 310. Those skilled in the art will understand that in some embodiments, the central rod may be a solid rod or a hollow rod; when a hollow rod is used, fluid can still be delivered through the central rod. Furthermore, in some other embodiments, the central rod is not a necessary structure and may be omitted, with the shape of the balloon body 310 changed solely by inflating or deflated fluid.

[0064] The specific structures of the aforementioned operating handle 100, insertion tube 200, electrode plate 322, center rod, and other components can be referred to existing structures in related technologies. Considering that they are not directly related to the innovative content of this application and the technical problem to be solved, they will not be described in detail here.

[0065] It should be noted that the balloon catheter in the embodiments of this application can be an ablation catheter used to ablate the target tissue, for example, it can be used for pulsed electric field ablation; in addition, in some other embodiments, the balloon catheter in the embodiments of this application can also be a mapping catheter used to collect electrophysiological signals of the target tissue.

[0066] During repeated inflation and deflation of the balloon catheter, the flexible circuit board 320 may separate from the balloon 310. In addition, the flexible circuit board 320 may also limit the smaller diameter of the balloon 310 after it is deflated. Since the balloon catheter generally needs to enter and exit through a sheath, and the diameter of the sheath is small, the outer diameter of the catheter electrode assembly 300 of the balloon catheter is also limited, for example, it needs to be less than 4 mm, or even less than 3 mm.

[0067] In addition to considering improving the adhesion strength between the flexible circuit board 320 and the capsule 310 and reducing the number of parts inside the capsule 310, the embodiments of this application have designed the conductive lines 323 of the electrode sheet 322 in the flexible circuit board 320, which is beneficial to improving the compliance of the flexible circuit board 320, facilitating the improvement of the connection reliability between the flexible circuit board 320 and the capsule 310, and enabling the conduit electrode assembly 300 to form a smaller diameter after shrinking.

[0068] In some embodiments, referring to Figures 4 to 6, the flexible circuit board 320 may mainly include an insulating substrate 321, an electrode sheet 322, a conductive line 323, an edge insulating layer 324, and a line insulating layer 325.

[0069] The conductive line 323 is attached to the surface of the insulating substrate 321 and is connected to the electrode sheet 322 to realize power transmission. The conductive line 323 can be made of materials and forming methods commonly used in the field of flexible circuit boards, such as copper foil, and formed on the insulating substrate 321 by etching, laser cutting or engraving. The specific material and forming method are not limited.

[0070] The insulation layer 325 is configured corresponding to the conductive line 323, meaning its shape and size match the conductive line 323 to primarily cover it. The insulation layer 325, covering the side of the conductive line 323 away from the insulating substrate 321, prevents the conductive line 323 from being exposed. The insulating substrate 321 has exposed areas not covered by the insulation layer 325. The insulation layer 325 provides insulation for the conductive line 323, ensuring reliable power transmission, preventing contact between the conductive line 323 and other lines or conductive structures, and also preventing unwanted discharges from contact with blood or patient tissue. The method of forming the insulation layer 325 is not limited, as long as it effectively covers and insulates the conductive line 323. For example, the circuit insulation layer 325 can be a PI film, which is bonded to the insulating substrate 321 and the conductive circuit 323 by means of bonding, hot pressing, etc.; or the circuit insulation layer 325 can be a coating layer, and the material can be solder resist ink, photoresist, polyimide, acrylic resin, silicon dioxide, etc.

[0071] Using the above method, the conductive line 323 is directly formed on the flexible circuit board 320, without the need for separate wiring. The structure is simple and helps to reduce the number and types of parts in the conduit electrode assembly 300. At the same time, the circuit insulation layer 325 provided corresponding to the conductive line 323 not only meets the insulation requirements of the conductive line 323, but also avoids the overall thickness of the insulation substrate 321 from increasing. This helps the flexible circuit board 320 to have higher compliance, facilitates the reliable adhesion between the flexible circuit board 320 and the capsule 310, and also makes it easier for the flexible circuit to shrink with the capsule 310, thereby enabling the conduit electrode assembly 300 to have a smaller diameter after shrinkage.

[0072] In some embodiments, the electrode sheet 322 is attached to the surface of the insulating substrate 321. The flexible circuit board 320 includes an edge insulating layer 324 corresponding to the edge of the electrode sheet 322. The shape of the edge insulating layer 324 is consistent with the shape of the edge of the electrode sheet 322. The edge insulating layer 324 has an electrode covering portion 3241 and a substrate connecting portion 3242. The electrode covering portion 3241 covers the edge surface of the electrode sheet 322. The substrate connecting portion 3242 and the electrode covering portion 3241 form a stepped structure. The stepped structure is used to match the thickness of the edge of the electrode sheet 322. The substrate connecting portion 3242 is connected to the insulating substrate 321. The edge insulating layer 324 can prevent electric arcing at the edge of the electrode sheet, which is beneficial to improving the uniformity of the electric field and the reliability of operation. Referring to FIG4, the edge insulating layer 324 around the near-end electrode sheet can be integrated with the line insulating layer of the first line.

[0073] In some embodiments, the flexible circuit board 320 has an edge portion located around the electrode sheet 322, and at least a portion of the edge portion has through holes 3211 distributed thereon. The through holes 3211 can reduce the strength of the edge portion and improve its compliance, thereby better preventing the insulating portion of the edge of the flexible circuit board 320 from peeling off from the capsule 310.

[0074] Referring to Figures 4 and 5, in one embodiment, the flexible circuit board 320 includes a proximal portion 3281, a distal portion 3282, and an intermediate connecting portion 3283. The proximal portion 3281 and the distal portion 3282 are respectively disposed on the proximal side and the distal side of the capsule 310. The intermediate connecting portion 3283 connects the proximal portion 3281 and the distal portion 3282. The width of the intermediate connecting portion 3283 is smaller than the width of the proximal portion 3281 and the distal portion 3282. The electrode sheet 322 includes a proximal electrode sheet 3221 disposed on the proximal portion 3281 and a distal electrode sheet 3222 disposed on the distal portion 3282.

[0075] The aforementioned proximal electrode 3221 and distal electrode 3222 are arranged along the proximal-distal direction of the catheter electrode assembly 300, creating conditions for a uniform electric field to be formed throughout the entire catheter electrode assembly 300. This allows the catheter electrode assembly 300 to adhere to the target tissue in a more flexible manner, such as with the distal end facing the target tissue, the distal end obliquely facing the target tissue, the side facing the target tissue, or the proximal end obliquely facing the target tissue. Simultaneously, the intermediate connecting portion 3283 can position the relative positions between the proximal portion 3281 and the distal portion 3282, thus better ensuring the relative positions of each electrode 322. The circumferential dimension of the intermediate connecting portion 3283 along the capsule 310 can be smaller than that of the proximal portion 3281 and the distal portion 3282. Since the diameter of the middle part of the capsule 310 changes significantly in the proximal-distal direction during the inflation and deflation of the balloon electrode assembly, a thinner intermediate connecting portion 3283 helps reduce the stress between the flexible circuit board 320 and the capsule 310 during inflation and deflation, thus helping to prevent the flexible circuit board 320 from peeling off. In one specific embodiment, the proximal electrode 3221 and the distal electrode 3222 can be symmetrically arranged on both sides of the capsule 310 in the proximal-distal direction.

[0076] In addition, the aforementioned thin strip-shaped intermediate connecting portion 3283 allows the catheter electrode assembly 300 to form a cylindrical shape with high axial strength when the capsule 310 is in a contracted state. When the surgeon pushes the catheter electrode assembly 300 into the sheath, it helps the catheter electrode assembly 300 to always maintain a cylindrical shape, preventing abnormal bulging of the catheter electrode assembly 300 in the sheath due to a long pushing path, and preventing the electrode pad 322 from scraping the inner wall of the sheath.

[0077] In one embodiment, the proximal electrode 3221 forms a proximal gradient region (as shown in Figure 4, the region between two double-dotted lines on the proximal electrode 3221), the size of which gradually narrows from the middle of the proximal end of the capsule 310 towards the proximal end of the capsule 310 along the circumferential direction; the distal electrode 3222 forms a distal gradient region (as shown in Figure 4, the region between two double-dotted lines on the distal electrode 3222), the size of which gradually narrows from the middle of the proximal end of the capsule 310 towards the distal end of the capsule 310 along the circumferential direction of the capsule 310.

[0078] By simultaneously setting proximal electrode 3221 and distal electrode 3222, and making proximal electrode 3221 form a proximal gradient region and distal electrode 3222 form a distal gradient region, the balloon electrode assembly can generate an electric field in the proximal, distal, and proximal-distal directions. The shape of the electric field matches the shape of the balloon body, and the electric field coverage is comprehensive. Furthermore, the proximal and distal gradient regions can adapt to the characteristic that the diameter is large in the proximal-distal direction after the balloon electrode assembly is inflated, and the diameter gradually decreases towards the proximal and distal ends. The electric field distribution is more uniform, which makes it easier for the balloon catheter to achieve ablation in a more flexible posture. In addition, since the proximal electrode 3221 and the distal electrode 3222 are respectively located on the proximal and distal sides of the balloon body 310, and in conjunction with the proximal and distal gradient regions, when the balloon electrode assembly contracts, as shown in Figure 7, the middle part of the balloon electrode assembly in the proximal-distal direction can form higher structural stability by relying on the proximal electrode 3221 and the distal electrode 3222. The proximal and distal ends can form a smaller outer diameter, which facilitates the passage through the narrow sheath. This allows the balloon catheter to move more smoothly back and forth in the sheath, making it easier for the balloon catheter to enter and exit the human body, reducing vascular access damage, and at the same time achieving continuity of ablation and large-area coverage.

[0079] The aforementioned proximal and distal gradient regions can be arranged symmetrically or asymmetrically on both sides of their width direction (i.e., along the circumference of the balloon body 310). For example, one side of the width direction can be straight relative to the axis of the balloon electrode assembly, while the other side can be inclined relative to the axis of the balloon electrode assembly. A symmetrical arrangement is more conducive to ensuring the morphological stability of the balloon electrode assembly during inflation and deflation.

[0080] In one embodiment, referring to Figures 4 and 5, both the proximal and distal ends of the proximal electrode 3221 are arc-shaped, with a proximal gradient region located between the two arcs; both the proximal and distal ends of the distal electrode 3222 are arc-shaped, with a distal gradient region located between the two arcs. The arc-shaped structure at the distal end of the electrode 322, as described above, is more conducive to the contraction of the balloon body 310 and can also form a guiding structure, facilitating the entry and exit of the balloon catheter from the sheath.

[0081] The aforementioned proximal electrode 3221 and distal electrode 3222 respectively form the first electrode and the second electrode. In order to realize the separate connection of different electrode plates 322 with the corresponding ablation host or mapping host, the conductive line 323 on the flexible circuit board 320 includes the first line 3231 and the second line 3232, which are respectively connected to the first electrode and the second electrode.

[0082] Each conductive line 323 can be disposed on the same side of the insulating substrate 321 or on different sides of the insulating substrate 321. In the case where there are two or more electrode plates 322 on a single flexible circuit board 320, the conductive line 323 connected to the electrode plate 322 located at the far end can pass through the side of the insulating substrate 321 away from the electrode plate 322 located at the near end.

[0083] Please refer to Figures 4 and 5. In one specific embodiment, the first line 3231 is located on the side of the insulating substrate 321 where the electrode sheet 322 is provided, and the second line 3232 is located on the side of the insulating substrate 321 opposite to the electrode sheet 322. The second line 3232 and the second electrode sheet are electrically connected by a conductive structure passing through the insulating substrate 321. Both the first line 3231 and the second line 3232 extend to one end of the insulating substrate 321 along the arrangement direction of the first electrode sheet and the second electrode sheet, for example, the proximal end of the insulating substrate 321, i.e., the lead-out portion 3284.

[0084] Compared to placing the conductive lines 323 on the edge of the electrode sheet 322 and arranging them side-by-side with the electrode sheet 322 along the surface of the capsule 310, in the illustrated embodiment, placing the conductive lines 323 on different sides of the insulating substrate 321 helps to reduce the width of the strip-shaped flexible circuit board 320. This allows the electrode sheet 322 of the flexible circuit board 320 to have a larger size along the circumference of the capsule 310, which is beneficial for forming a more balanced electric field and also helps to prevent the electrode sheet 322 from being damaged due to excessive current concentration during discharge.

[0085] In addition, the conductive line 323 connected to the distal electrode 3222 can pass through the intermediate connection portion 3283, which can enhance the overall axial strength of the flexible circuit board 320 where the intermediate connection portion 3283 is provided, and help the conduit electrode assembly 300 to better maintain its cylindrical shape.

[0086] It should be noted that the conductive structure used to achieve the conductive connection between the front and back sides of the insulating substrate 321 can adopt existing methods in the field of flexible circuit boards, and the specific structural form is not limited. For example, it can be a via 327 passing through the insulating substrate 321, i.e., a metallized via. Alternatively, a conductive layer can be provided on the lateral surface of the edge of the insulating substrate 321 where it intersects with the surface of the insulating substrate 321, and the conductive connection between the front and back sides of the insulating substrate 321 can be achieved by relying on the conductive layer. Referring to Figures 4 and 5, multiple vias 327 can be provided between the distal electrode 322 and the second line 3232 for conduction to ensure the current flow area.

[0087] In some embodiments, the flexible circuit board 320 may include a lead-out portion 3284 disposed at the proximal end of the flexible circuit board 320, through which conductive lines 323 are led out, and the width of the lead-out portion 3284 is smaller than the width of the adjacent portion. During balloon catheter assembly, the conductive lines 323 on each flexible circuit board 320 can be connected to wires at the proximal end of the catheter electrode assembly 300, and then led along the insertion tube 200 to the operating handle 100, thereby realizing the circuit connection between the catheter electrode assembly 300 and the ablation host or mapping host.

[0088] The flexible circuit board 320 may include pads fixed on an insulating substrate 321. The pads are connected to the end of the conductive line 323 furthest from the electrode plate 322, and the pads are used for soldering wires to transmit electrical energy. The pads facilitate conductive connection between the conductive line 323 and the wires; the technology is mature and easy to manufacture. Considering the ease of soldering the wires, in some embodiments, the first pad 3261 connected to the first line 3231 and the second pad 3262 connected to the second line 3232 may be located on the same surface of the insulating substrate 321. A corresponding conductive structure (e.g., multiple vias 327) may be provided between the second pad 3262 and the second line 3232 to ensure sufficient current flow area. Of course, in some other embodiments, the first pad 3261 and the second pad 3262 may also be located on two opposite surfaces of the insulating substrate 321.

[0089] In some embodiments, the pads corresponding to the first and second electrodes are both disposed on the lead-out portion 3284 near the end of the flexible circuit board 320, which facilitates the connection of the conductive line 323 to the wire in the insertion tube 200. At least a portion of the first line 3231 and the second line 3232 may be spaced apart in the width direction of the flexible circuit board 320, which avoids the first line 3231 and the second line 3232 overlapping in the thickness direction of the flexible circuit board 320, resulting in a larger thickness in the corresponding part. In a specific embodiment, referring to FIG4, the second line 3232 is located on the back side of the insulating substrate 321 in the figure, indicated by a dashed line, and a section of the second line 3232 on the lead-out portion 3284 is spaced apart from the first line 3231 in the width direction of the flexible circuit board 320.

[0090] In the above embodiments, the flexible circuit board 320 includes a proximal portion 3281 and a distal portion 3282, with the first electrode and the second electrode respectively disposed on the proximal portion 3281 and the distal portion 3282 of the flexible circuit board 320. In some other embodiments, the flexible circuit board 320 may also adopt other arrangements. For example, the flexible circuit board 320 may only be disposed on the distal side of the capsule 310, or the flexible circuit board 320 may only be disposed on the distal side of the capsule 310, or it may partially extend to the proximal portion 3281 of the capsule 310. In addition, in some other embodiments, the number of electrode pieces 322 on a single flexible circuit board 320 may be only one, or more than three may be provided.

[0091] By placing the conductive lines 323 of the electrode pads 322 onto the insulating substrate 321 and providing a circuit insulation layer 325 for the conductive lines 323, the flexible circuit board 320 of the catheter electrode assembly 300 exhibits better compliance and more reliable connection with the capsule 310. This facilitates a denser circumferential distribution of the electrode pads 322, forming a more uniform and stable ablation area. Furthermore, the catheter electrode assembly 300 achieves a smaller outer diameter after contraction, making it easier to pass through narrow sheaths and allowing for easier entry and exit from the human body, thus reducing vascular access damage.

[0092] Embodiments of the catheter electrode assembly in this application:

[0093] The catheter electrode assembly includes a balloon body 310 and a flexible circuit board 320. The specific structure of the catheter electrode assembly 300 can be the same as that of the catheter electrode assembly 300 in any embodiment of the balloon catheter described above, and will not be described again here.

[0094] An embodiment of the flexible circuit board for the catheter electrode assembly in this application:

[0095] The specific structure of the flexible circuit board of the catheter electrode assembly can be the same as that of the flexible circuit board 320 in any embodiment of the balloon catheter described above, and will not be repeated here.

[0096] The above examples illustrate this application only to aid understanding and are not intended to limit its scope. Those skilled in the art to which this application pertains can make various simple deductions, modifications, or substitutions based on the ideas presented.

Claims

1. A flexible circuit board for a catheter electrode assembly, characterized in that, include: An insulating substrate, said insulating substrate being attached to the balloon surface of the balloon catheter; Electrode plates, which are fixed on the insulating substrate, are used to transmit electrical energy; A conductive line is attached to the surface of the insulating substrate and connected to the electrode sheet to achieve electrical energy transmission; And a line insulation layer corresponding to the conductive line, the line insulation layer covering the conductive line, the insulating substrate having an exposed area not covered by the line insulation layer.

2. The flexible circuit board as described in claim 1, characterized in that, The electrode sheet includes a first electrode sheet and a second electrode sheet, and the conductive line includes a first line and a second line, wherein the first line and the second line are respectively connected to the first electrode sheet and the second electrode sheet; The first line is located on the side of the insulating substrate where the electrode sheet is located, and the second line is located on the side of the insulating substrate opposite to the electrode sheet. The second line is electrically connected to the first electrode sheet by means of a conductive structure passing through the insulating substrate. Both the first line and the second line extend to one end of the insulating substrate along the arrangement direction of the first and second electrode sheets.

3. The flexible circuit board as described in claim 2, characterized in that, At least a portion of the first line and the second line are spaced apart in the width direction of the flexible circuit board.

4. The flexible circuit board as described in claim 2, characterized in that, The flexible circuit board includes pads fixed on the insulating substrate, the pads being connected to the end of the conductive line away from the electrode sheet, and the pads being used for soldering wires to transmit electrical energy.

5. The flexible circuit board as described in claim 4, characterized in that, The first pad connected to the first line and the second pad connected to the second line are located on the same surface of the insulating substrate.

6. The flexible circuit board as described in claim 4, characterized in that, The flexible circuit board includes a lead-out portion disposed near the proximal end of the flexible circuit board, the lead-out portion for the conductive lines to be led out, the width of the lead-out portion being smaller than the width of the adjacent portion, and the pads being disposed on the lead-out portion.

7. The flexible circuit board as described in any one of claims 1 to 6, characterized in that, The flexible circuit board includes a proximal portion, a distal portion, and an intermediate connecting portion. The proximal portion and the distal portion are respectively disposed on the proximal side and the distal side of the capsule. The intermediate connecting portion connects the proximal portion and the distal portion, and the width of the intermediate connecting portion is smaller than the width of the proximal portion and the distal portion. The electrode includes a proximal electrode disposed on the proximal portion and a distal electrode disposed on the distal portion. The conductive line connected to the distal electrode passes through the intermediate connecting portion.

8. The flexible circuit board as described in any one of claims 1 to 6, characterized in that, The electrode sheet is attached to the surface of the insulating substrate. The flexible circuit board includes an edge insulating layer corresponding to the edge of the electrode sheet. The shape of the edge insulating layer is consistent with the shape of the edge of the electrode sheet. The edge insulating layer has an electrode covering portion and a substrate connecting portion. The electrode covering portion covers the edge surface of the electrode sheet. The substrate connecting portion and the electrode covering portion form a stepped structure. The stepped structure is used to match the thickness of the edge of the electrode sheet. The substrate connecting portion is connected to the insulating substrate.

9. A catheter electrode assembly, characterized in that, include: A capsule, which can expand and contract; And a flexible circuit board, wherein the flexible circuit board is any one of claims 1 to 8.

10. A balloon catheter, characterized in that, include: Operating handle; An insertion tube is connected to the distal end of the operating handle; And a catheter electrode assembly, the balloon assembly being connected to the distal end of the insertion tube, the catheter electrode assembly including a balloon body and a flexible circuit board, the balloon body being inflatable and contractible, the flexible circuit board being attached to the balloon body, the flexible circuit board being the flexible circuit board of any one of claims 1 to 8.

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