A mapping catheter tip and method of making the same

Abstract

This invention discloses a mapping catheter tip and its preparation method. The mapping catheter tip includes a flexible film, electrodes, electrode wires, a support member, and a tube body. The flexible film includes a surface film and a base film. The electrodes are arrayed on the base film, and each electrode is individually connected to an electrode wire. One end of the electrode wire is integrated into the flexible film, and the other end extends into the tube body. The surface film has a perforated structure, with the electrodes exposed from the perforations. The support member includes at least one support arm, at least one side of which is bonded to the flexible film. The proximal ends of the support arms converge and are bonded to a joint portion of the support member, which is then fixed within the tube body. Integrating the electrode and electrode wire components into the flexible film simplifies the electrode installation process for high-density mapping catheters with multiple electrodes, improving production efficiency. This invention distributes the electrodes within the flexible film, thus making the design independent of the support member. The support member can adopt various forms.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a mapping catheter head end and a preparation method thereof. BACKGROUND

[0002] Generally, the number of mapping electrodes of a high-density mapping catheter is relatively large, and the spacing between the electrodes is relatively small. The electrodes of the current high-density mapping catheter are mostly distributed on a small tube to form electrode arms. Different spatial configurations of the mapping head end, such as claw-shaped, spherical, planar, etc., are formed by combining different numbers and shapes of electrode arms. The shape of the electrodes is mostly ring-shaped. The traditional electrode installation method is to weld a single electrode and an electrode wire and then fix the electrode on the electrode arm. In this process, it is necessary to ensure that the electrode is installed in the correct position, the electrode is not deformed, and the electrode wire is not damaged. Because the number of electrodes of the high-density mapping catheter is relatively large, and the size of the electrodes is relatively small, it takes a lot of time and very fine operation to weld and install the electrodes using this method. Moreover, each electrode in this process may have problems, resulting in unqualified products. As the number of electrodes increases, the difficulty increases.

[0003] In addition, the head end structure of the high-density mapping catheter is generally more complex than that of the ordinary electrophysiological catheter, and is mostly a special-shaped structure. When in use, the head end needs to be expanded so that the electrodes can contact the endocardium to collect electrical signals. Before and after use, the head end needs to be able to fold and shrink into a sheath. In addition to considering the distribution of the electrodes, the shape of the electrode arm also needs to consider the problem of entering and exiting the sheath, and it is often difficult to balance the two.

[0004] The emergence of printed circuit boards simplifies the assembly and welding of electronic components, reduces labor intensity, improves work efficiency and product reliability. In the head end of the high-density mapping catheter, if the electrodes and electrode wires can be integrated on a flexible film like the manufacturing process of a printed circuit board, the above problems can be solved. SUMMARY

[0005] The present application aims to: in view of the problems in the prior art that the electrodes of the high-density mapping catheter are relatively small and the number is relatively large compared with the ordinary electrophysiological catheter, the traditional electrode installation method has a large time cost and is prone to errors, and the typical high-density mapping catheter mostly arranges the electrodes on the electrode arm, and the configuration of the electrode arm needs to meet the requirements of electrode distribution and the expansion and contraction of the overall structure, and it is often difficult to balance the two, the present application provides a mapping catheter head end and a preparation method thereof.

[0006] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is:

[0007] A mapping catheter tip includes a flexible film, electrodes, electrode wires, a support member, and a tube body. The flexible film includes a surface film and a base film. The electrodes are arrayed on the base film, and each electrode is individually connected to an electrode wire. One end of the electrode wire is integrated into the flexible film, and the other end extends into the tube body. The surface film has a perforated structure, and the electrodes are exposed from the perforated portion of the surface film. The support member includes at least one support arm, at least one side of which is coupled to the flexible film. The proximal ends of the support arms converge and are coupled to a joint portion of the support member, which is fixedly installed in the tube body.

[0008] This invention integrates the electrode and electrode wire structures into a flexible film, simplifying the electrode installation process of high-density mapping catheters with multiple electrodes and improving production efficiency. Compared to the conventional method of mounting electrodes on support components, this invention distributes the electrodes within the flexible film, making the design independent of the support component. The support component can adopt various forms to adapt to different needs. Furthermore, with the electrodes fixed within the flexible film, the movement of the flexible film in the expanded state is a whole-body movement, while the electrode positions remain relatively fixed, improving mapping accuracy. Finally, this invention also integrates at least one side of the support arm with the flexible film. Compared to integrating the end face of the support arm with the flexible film, the side contact area is larger, providing sufficient support and adhesion to the flexible film, ensuring consistent shape changes between the support arm and the flexible film, and allowing for more precise control of the flexible film by the surgeon.

[0009] In a preferred embodiment of the present invention, at least two sides of the support arm are bonded to the flexible film. This provides greater support and adhesion to the flexible film, making the shape changes of the support arm and the flexible film more consistent, and allowing the surgeon to have more precise control over the flexible film. More preferably, all sides of the support arm are bonded to the flexible film.

[0010] As a preferred embodiment of the present invention, the base film is provided with a channel, and the support arm is inserted into the channel and fixed, so that all sides of the support arm are combined with the flexible film, which can provide greater support and adhesion to the flexible film, making the shape changes of the support arm and the flexible film more consistent, and allowing the surgeon to control the flexible film more precisely.

[0011] As a preferred embodiment of the present invention, the support arm is hot-pressed and wrapped around the base film, so that all sides of the support arm are combined with the flexible film, which can provide greater support and adhesion to the flexible film, making the shape changes of the support arm and the flexible film more consistent, and allowing the surgeon to have more precise control over the flexible film.

[0012] As a preferred embodiment of the present invention, the flexible film further includes a fixing layer, wherein the base film is disposed between the surface film and the fixing layer, and the fixing layer is used to increase the strength and toughness of the flexible film.

[0013] As a preferred embodiment of the present invention, the fixing layer is provided with a channel, and the support arm is inserted into the channel, so that all sides of the support arm are combined with the flexible film, which can provide greater support and adhesion to the flexible film, making the shape changes of the support arm and the flexible film more consistent, and allowing the surgeon to control the flexible film more precisely.

[0014] As a preferred embodiment of the present invention, the support arm is hot-pressed and wrapped around the fixing layer, so that all sides of the support arm are combined with the flexible film, which can provide greater support and adhesion to the flexible film, making the shape changes of the support arm and the flexible film more consistent, and allowing the surgeon to have more precise control over the flexible film.

[0015] As a preferred embodiment of the present invention, the support arm has a smooth transition structure to obtain sufficiently low resistance when entering and exiting the sheath. It is understood that the more complex the support arm structure, the more bending points or joints it has, the less likely it is to be folded into a smaller size, and the greater the resistance when entering and exiting the sheath.

[0016] As a preferred embodiment of the present invention, the support arm has a flat structure to reduce lateral deformation, and more preferably, the aspect ratio of the support arm is 1-20.

[0017] As a preferred embodiment of the present invention, the electrode and the electrode wire are integrally formed components, which are easy to process, and the electrode wire extends along the contraction direction of the support component.

[0018] As a preferred embodiment of the present invention, the electrode wire is serrated or wavy in shape, providing a certain margin for deformation and reducing the probability of electrode wire breakage.

[0019] As a preferred embodiment of the present invention, the flexible thin film and the electrode are integrated by vapor deposition, which is easy to process and has high processing accuracy.

[0020] The present invention also discloses a mapping catheter, including the aforementioned mapping catheter tip.

[0021] This invention also discloses a method for preparing a mapping catheter tip, used to fabricate the aforementioned mapping catheter tip, comprising the following steps:

[0022] Step 1: Coat the base film with a layer of photoresist;

[0023] Step 2: Use a photolithography machine to etch a photolithographic portion onto the photoresist that matches the pattern of the electrode and the electrode lines;

[0024] Step 3: Deposit conductive material onto the photolithographic area using vapor deposition;

[0025] Step 4: Remove the photoresist.

[0026] This invention also discloses a method for preparing a mapping catheter tip, used to fabricate the aforementioned mapping catheter tip, comprising the following steps:

[0027] Step 1: Attach a layer of conductive material onto the base film by deposition or adhesion;

[0028] Step 2: Cover the surface of the conductive material with a layer of photoresist;

[0029] Step 3: Use a photolithography machine to remove the photoresist outside the electrodes and electrode lines to expose the conductive material;

[0030] Step 4: Remove the exposed conductive material using chemical etching or physical etching.

[0031] Step 5: Remove the remaining photoresist to expose the electrodes and electrode lines.

[0032] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0033] 1. This invention integrates the electrode and electrode wire structures into a flexible thin film, simplifying the electrode installation process of high-density multi-electrode mapping catheters and improving production efficiency.

[0034] 2. Compared to the conventional approach of mounting electrodes on a support member, this invention distributes the electrodes in a flexible film, thus making the design independent of the support member. The support member can take various forms to meet different needs.

[0035] 3. The electrodes are fixed in the flexible film. In the expanded state, the movement of the flexible film is as a whole, while the position of the electrodes remains relatively fixed, which improves the accuracy of the measurement.

[0036] 4. By combining at least one side of the support arm with the flexible film, compared to combining the end face of the support arm with the flexible film, the contact area of ​​the side is larger, which can provide sufficient support and adhesion to the flexible film, so that the shape change of the support arm and the flexible film are consistent, and the surgeon can have more precise control over the flexible film. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of the tip of a high-density mapping catheter according to the present invention.

[0038] Figure 2This is a schematic diagram of the structure of the base film with integrated electrodes described in this invention.

[0039] Figure 3 This is a schematic diagram of the structure of the film and its hollowed-out pattern described in this invention.

[0040] Figure 4 This is a structural schematic diagram of the fixing layer and supporting components fixing channel described in this invention.

[0041] Figure 5 This is a structural schematic diagram of a support member according to the present invention.

[0042] Figure 6 This is a structural schematic diagram of another support component described in this invention.

[0043] Figure 7 This is a structural schematic diagram of another support component described in this invention.

[0044] Figure 8 This is a structural schematic diagram of the cross-section of the support arm described in this invention.

[0045] Figure 9 This is a schematic diagram of a method for depositing electrodes and electrode lines on a base film according to the present invention.

[0046] Figure 10 This is a schematic diagram of a method for depositing electrodes and electrode lines on a base film according to the present invention.

[0047] Icons: 1-Flexible film, 11-Surface film, 111-Surface film cutout, 12-Base film, 13-Fixing layer, 131-Channel, 2-Electrode, 3-Electrode line, 4-Supporting component, 41-Supporting arm, 411-Proximal end of supporting arm, 412-First side of supporting arm, 413-Second side of supporting arm, 42-Joint of supporting component, 5-Tube body, 6-Photoresist, 7-Conductive material. Detailed Implementation

[0048] The present invention will now be described in detail with reference to the accompanying drawings.

[0049] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0050] Example 1

[0051] The catheter involved in this invention is a high-density mapping catheter, which can be used for cardiac electrophysiological signal mapping. The tip of the high-density mapping catheter consists of a flexible membrane 1, electrodes 2, electrode wires 3, a support member 4, and a tube body 5. The flexible membrane 1 has a multi-layered structure, including at least a surface membrane 11 and a base membrane 12. Electrodes 2 and electrode wires 3 are integrated on the base membrane 12. The surface membrane 11 has a perforated structure, providing protection for the electrodes 2 and electrode wires 3. Electrodes 2 are exposed from the perforated portion of the surface membrane 11 and are arrayed on the surface of the flexible membrane 1. Each electrode 2 is individually connected to an electrode wire 3. The support member 4 is made of highly elastic metal or plastic and includes at least one support arm 41. At least one side of the support arm 41 is bonded to the flexible membrane 1. The proximal ends 411 of the support arms converge and are bonded to a support member junction 42. The support member junction 42 is installed and fixed within the tube body 5.

[0052] The base film 12 and the surface film 11 are made of a polymer material with good electrical insulation properties, with a thickness of 0.01 mm to 1 mm. Electrodes 2 and electrode lines 3 are distributed on the base film 12 in a specific pattern. The surface film 11 has a perforated pattern that is basically consistent with the electrode distribution pattern and is attached to the surface of electrodes 2 and electrode lines 3. At this point, the perforated portion 111 of the surface film 11 just exposes the electrodes 3, while the electrode lines 3 are embedded between the two thin films. The combination of the surface film 11 and the base film 12 forms a flexible integrated electrode array. The flexible thin film 1 may also include a fixing layer 13, located below the base film 12, which is bonded to the base film 12 by adhesive bonding or hot pressing. The fixing layer 13 is used to increase the strength and toughness of the thin film, to bond with the support member 4, and to provide adhesion for the thin film. Figure 1 The figure shown is an overall schematic diagram of a catheter tip according to the present invention. Figure 2 for Figure 1 A schematic diagram of a base film integrating electrodes and electrode lines in its structure. Figure 3 This is a schematic diagram of the perforated pattern on the film. Figure 4 This is a schematic diagram of the fixed layer.

[0053] The support member 4 is made of a metal or non-metal material with good elasticity, which provides adhesion and support for the flexible film 1. Figures 5-7 The diagram shows several configurations of the support member. The support member 4 has two forms: a contracted state and an expanded state. In the contracted state, the support member 4 and the membrane 1 contract to facilitate entry and exit from the sheath. In the expanded state, the support member 4 expands the flexible membrane 1, and the electrodes 2 are laid out according to the designed spacing and pattern for electrophysiological signal acquisition. The support member 4 includes one or more support arms 41 and a support member connecting portion 42. The proximal ends 411 of the support arms converge and are fixed at the connecting portion, which is then fixed within the tube body 5. The support arms 41 and the connecting portion 42 can be integrally formed or combined to form the support member 4.

[0054] The shape of the support arm 41 is not limited, but preferably the support arm 41 should be a straight arm or an arm with a smooth transition to obtain sufficiently small resistance when entering and exiting the sheath. It is understood that the more complex the structure of the support arm 41, the more bending points or joints there are, the less likely it is to be folded into a smaller size, and the greater the resistance when entering and exiting the sheath.

[0055] The cross-sectional shape of the support arm 41 is not limited. Specifically, the support arm 41 is flattened to reduce lateral deformation, with an aspect ratio A / B of 1 to 20. The expansion and contraction of the flexible film 1 depends entirely on the surgeon's control over the configuration of the support arm 41. Therefore, the more fully the flexible film 1 is bonded to the support arm 41, the more consistent the morphological changes of the support arm 41 and the more precise the surgeon's control over the flexible film 1. For a slender support arm 41, bonding only to the end face or a portion thereof is insufficient to provide sufficient support and adhesion for the flexible film 1. Therefore, in this invention, the support arm 41 has at least one side bonded to the flexible film 1. Figure 8 The diagram shows a flat support arm 41 with a rectangular cross-section. The first side 412 and the second side 413 of the support arm 41 are shown; the third and fourth sides are not shown. One or more of these sides are bonded to a flexible film. When the support arm 41 is inserted into the channel 131 of the flexible film bonding layer, all four sides are bonded to the flexible film 1.

[0056] Furthermore, from a surface morphology perspective, smooth surfaces in a blood environment can reduce thrombus formation, while rough surfaces tend to facilitate thrombus formation. In this invention, the support arm 41 has a simple structure and can be completely enclosed in the flexible film 1, making it easier to achieve a smooth and flat surface on all surfaces exposed to the blood environment. Compared to complex (e.g., woven) and exposed support members 4, this can reduce thrombus formation to a certain extent.

[0057] The electrodes 2 can be distributed in any shape on the flexible film 1. The electrodes 2 can be evenly distributed or non-evenly distributed as needed, with a spacing of 0.1 mm to 10 mm between them. The electrodes 2 are generally sheet-like, and the shape of the surface in contact with the tissue is not limited. Specifically, they can be square, polygonal, circular, or one or more other shapes. The thickness of the electrodes 2 is 0.01 mm to 1 mm. Figure 1 The diagram shows an example of circular electrodes evenly distributed in the transverse and longitudinal directions of a circular thin film. Electrode 2 is made of a metal or non-metal material with good electrical conductivity, such as copper, gold, silver, or graphene. Specifically, if electrode 2 is made of copper, its surface requires anti-oxidation treatment.

[0058] Each electrode 2 is connected to an electrode wire 3. The electrode wire 3 is integrally formed with the electrode 2 and is made of the same material. The distribution of the electrode wires 3 within the flexible film 1 is designed according to the shape of the supporting member 4, extending along the contraction direction of the supporting member 4. Figure 2The diagram shows one arrangement of the electrode wires 3. The corresponding support member 4 for this arrangement is as follows: Figure 7 The structure is a centrally divergent type. As the support arm 41 contracts towards the center, the electrode wires 3 converge from the edge towards the center. In some configurations, the flexible film 1 deforms significantly during contraction and expansion, and some areas may need to withstand certain tension. The electrode wires 3 can be arranged in a serrated or wavy pattern to provide some margin for deformation and reduce the probability of electrode wire breakage. The electrode wires 3 in the film extend from the electrode end into the tube body 5.

[0059] After electrodes 2 and electrode lines 3 are distributed on the base film 12 according to the design pattern, a pre-prepared perforated surface film 11 is placed over the surfaces of electrodes 2 and electrode lines 3, so that electrodes 2 are just exposed from the perforated area 111, while electrode lines 3 are contained between the base film 12 and the surface film 11. Then, the fixing layer 13 is bonded to the base film 12. The fixing layer 13, base film 12, and surface film 11 are bonded together as a whole by hot pressing or bonding. The materials of the surface film 11 and base film 12 can be the same as or different from those of the fixing layer 13. The selection of materials for the surface film 11 and base film 12 mainly considers electrical insulation and bonding performance with the electrode materials. The fixing layer 13 mainly considers the overall flexibility of the film. When the strength and toughness of the surface film 11 and base film 12 meet the requirements, the fixing layer 13 is not needed, and the electrode lines 3 can be directly placed on the base film 12. The fixing layer 13 can be fixed to one surface of the support arm 41 of the support member 4 by adhesive bonding, or a channel 131 can be pre-drilled in the fixing layer 13 and the support arm 41 of the support member 4 can be inserted into the channel 131 for fixing. Alternatively, the support arm 41 of the support member 4 can be hot-pressed and wrapped in the fixing layer 13 during the film hot pressing process.

[0060] The aforementioned mapping catheter tip may also include one or more positioning sensors, preferably magnetic coil positioning sensors. The positioning sensors are distributed within the support member joint 42, or distributed on the support member joint 42 and one or more support arms 41. When used with a matching electrophysiological three-dimensional mapping system, the positioning sensors can transmit their location information to the host computer, and then display the position and morphology of the catheter tip through a series of algorithms.

[0061] Example 2

[0062] This invention also includes a method for fabricating a high-density mapping catheter tip. As described above, a flexible thin film integrated with electrodes is used. The integration of the electrodes and the thin film can be achieved through vapor deposition. Figure 9 This is a schematic diagram of a fabrication method. First, a layer of photoresist 6 is coated onto the base film 12. Figure 9 a). Then, a photolithography machine is used to etch the desired electrode 2 and electrode line 3 onto the photoresist. Figure 9b). Conductive material 7 is deposited on the photolithography section using vapor deposition. Figure 9 c). After removing the photoresist, electrode 2 and electrode line 3 are bonded to the base film according to the designed pattern. Figure 9 d).

[0063] Example 3

[0064] Unlike Example 2, this example discloses a method for preparing a high-density mapping catheter tip, which includes using photoresist in reverse. Figure 10 This is a schematic diagram. First, a layer of conductive material 7 is uniformly deposited on the surface of the base film 12 by deposition or adhesion. Figure 10 a). Then cover the surface with a layer of photoresist 6 ( Figure 10 b). Using a photolithography machine, the photoresist 6 outside of electrode 2 and electrode line 3 is removed to expose the conductive material 7. Figure 10 c). Remove the exposed conductive material 7 using chemical etching or physical etching. Figure 10 d). Finally, after removing the photoresist, electrode 2 and electrode lines 3 are distributed on the base film 12 according to the designed pattern. Figure 10 e). Plasma treatment can be used before depositing electrode material to increase the bonding strength between electrode 2 and base film 12. Electrode material deposition can only be performed on flat surfaces. For some more complex structures, the flexible film 1 may include curved sections, and the integration of electrode 2 and electrode line 3 may need to be completed in sections, ultimately assembled together by fixing layer 13.

[0065] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A mapping catheter tip, characterized in that, The device includes a flexible film (1), electrodes (2), electrode wires (3), a support member (4), and a tube (5). The flexible film (1) includes a surface film (11) and a base film (12). The electrodes (2) and electrode wires (3) are integrated on the base film (12). The electrodes (2) are arrayed on the base film (12). Each electrode (2) is individually connected to an electrode wire (3). One end of the electrode wire (3) is buried between the surface film (11) and the base film (12), and the other end extends into the tube (5). The electrode wire (3) extends along the contraction direction of the support member (4). The shape of the electrode wire (3) is serrated or wavy. The electrode (3) has a deformation allowance, the surface film (11) has a hollow structure, the electrode (2) is exposed from the hollow position of the surface film (11), the support member (4) includes at least one support arm (41), the flexible film (1) bonding layer is provided with a channel (131), the support arm (41) is inserted into the channel (131) and fixed, the support arm (41) has a flat structure, the length-to-width ratio of the support arm (41) is 1-20, the four sides of the support arm (41) are all combined with the flexible film (1), the near end of the support arm (41) converges and is combined with the support member bonding part (42), and the support member bonding part (42) is installed and fixed in the tube body (5).

2. The mapping catheter tip according to claim 1, characterized in that, The channel (131) is disposed on the base film (12).

3. The mapping catheter tip according to claim 1, characterized in that, The flexible film (1) further includes a fixing layer (13), and the base film (12) is disposed between the surface film (11) and the fixing layer (13).

4. The mapping catheter tip according to claim 3, characterized in that, The channel (131) is disposed on the fixed layer (13).

5. The mapping catheter tip according to claim 1, characterized in that, The support arm (41) has a smooth transition structure.

6. The mapping catheter tip according to claim 1, characterized in that, The electrode (2) and the electrode wire (3) are integrally formed components.

7. The mapping catheter tip according to claim 1, characterized in that, The flexible thin film (1) and the electrode (2) are integrated by vapor deposition.

8. A mapping catheter, characterized in that, Includes a mapping catheter tip as described in any one of claims 1-7.

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