A controllable bending calibration tube

Abstract

This utility model belongs to the field of medical device technology and discloses a controllable bending mapping catheter, including a catheter body and a support member. The catheter body includes a bendable section with a channel extending axially within it. The support member is fixedly disposed within the channel and extends axially along the channel. The support member includes at least three support segments, with the stiffness of the at least three support segments increasing axially from distal to proximal, so that the bendable section forms multiple stiffness segments axially. By setting a support member with gradually changing stiffness inside the bendable section, this utility model can enable the catheter to be delivered directly to the coronary sinus ostium after it is located, while ensuring that the mid-section electrode on the bendable section can effectively adhere to the curved physiological structure.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, and in particular to a controllable bending calibration catheter. Background Technology

[0002] Mapping catheters are interventional medical devices used to collect intracardiac biological signals and are widely used in cardiac electrophysiological examinations and radiofrequency ablation for arrhythmias. The routine surgical procedure for mapping catheters involves placing the catheter via puncture of the femoral vein or superior vena cava, then advancing it to the target site for signal extraction. Currently, commonly used mapping catheters in clinical practice are quadripolar and decapolar sizes. In routine procedures, two mapping catheters are often placed: a quadripolar catheter is typically placed in the right ventricle, and a decapolar catheter is typically placed in the coronary vein.

[0003] Coronary venous positioning electrode catheter placement is one of the classic locations for electrophysiological catheter placement. Coronary sinus catheter placement involves inserting the catheter from the coronary sinus ostium along the vein towards the upper left. Current mapping catheters are typically planar curved catheters. In clinical practice, after the catheter enters the right atrium, the catheter tip is pre-bent at approximately 60°, adjusting the tip to the left. Under auxiliary X-ray imaging, in the anteroposterior fluoroscopy, the coronary sinus should be 2–3 cm above the diaphragm, located between the midline of the spine and the left border; in the right anterior oblique fluoroscopy at 30°, the coronary sinus should be 2–3 cm upwards, located 2–3 cm lateral to the left border of the spine. The catheter is advanced appropriately. If no significant resistance is encountered, the catheter tip is rotated while it is advanced inwards, forming an angle of approximately 70° with the spine in the anterooblique view and approximately 45° in the anterior oblique view. In the left anterior oblique fluoroscopy at 30°, if the catheter is seen entering the spinal shadow nearly horizontally, it indicates that the catheter has reached the target location.

[0004] However, existing planar curved catheters have the following problems: 1. When in place, the catheter needs to be rotated and pushed along the side to reach the target site, which is difficult to operate clinically. If the rotation is excessive, the catheter can easily pop out of the sinus opening; 2. It is difficult to achieve complete contact between the electrode segments, resulting in inaccurate signal acquisition and affecting the diagnosis and treatment effect. Utility Model Content

[0005] The purpose of this application is to provide a controllable bending mapping catheter. By setting a support with gradually varying stiffness inside the bendable section, the catheter can be delivered directly to the coronary sinus ostium after it is located, while ensuring that the mid-section electrode on the bendable section can be effectively attached to the curved physiological structure.

[0006] The technical solution provided in this application is as follows:

[0007] A controllable bending calibration catheter, comprising:

[0008] The catheter body includes a bendable section, wherein the bendable section has a channel extending along its axial direction;

[0009] A support member is fixedly disposed within the channel and extends along the axial direction of the channel. The support member includes at least three support segments, the stiffness of which increases from the distal end to the proximal end along the axial direction, so that the bendable segment forms multiple stiffness segments along the axial direction.

[0010] In some embodiments, the at least three support segments include at least three layers of metal sheets, which are stacked sequentially in a direction perpendicular to the axial direction of the channel, and the length of the at least three layers of metal sheets gradually decreases along the stacking direction. The proximal end of the support is approximately flush with the distal end, and multiple steps are formed.

[0011] In some embodiments, at least two electrodes are also included, which are spaced apart along the axial direction of the bendable segment.

[0012] In some embodiments, it also includes electrode wires and bending control wires, the support dividing the channel into a first cavity and a second cavity, the electrode wires passing through the first cavity and electrically connected at their distal ends to the electrode;

[0013] The bending control line passes through the second cavity and its distal end is fixedly connected to the distal end of the support member.

[0014] In some embodiments, a retaining ring is also included, which is fixedly disposed at the distal end of the channel, and the distal end of the support member and the distal end of the control curve are respectively fixedly connected to the retaining ring.

[0015] In some embodiments, the catheter body further includes a main body segment and a bending control handle, the distal end of the main body segment being connected to the proximal end of the bendable segment; the bending control handle is disposed at the proximal end of the main body segment and is fixedly connected to the bending control line.

[0016] In some embodiments, at least two wire positioning elements are provided axially spaced along the bending control line.

[0017] In some embodiments, the pull-line positioning component includes a spring coil and a heat-shrink tubing, the spring coil being sleeved on the control bending line, and both ends of the spring coil being fixedly connected to the control bending line via the heat-shrink tubing; or;

[0018] The pull-line positioning component includes a heat-shrink tubing, which is fixedly sleeved onto the control bend line by a heat-shrink process.

[0019] In some embodiments, the support member has gaps between its two sides along its width direction and the inner wall of the channel, and the outer diameter of the pull-wire positioning member is larger than the width of the gaps.

[0020] In some embodiments, the distal end of the bendable segment is formed into a circular head by self-heating and melting.

[0021] In some embodiments, the support includes a first metal sheet, a second metal sheet, and a third metal sheet, which are stacked sequentially along a direction perpendicular to the axial direction of the channel, with their lengths decreasing sequentially. The proximal ends of the stacked first metal sheet, second metal sheet, and third metal sheet are approximately flush, while the distal ends form multiple steps, so that the bendable segment forms three segments with progressively increasing stiffness along the direction from its distal end to its proximal end.

[0022] In some embodiments, the length of the first metal sheet ranges from 40 to 200 mm; the length of the second metal sheet ranges from 15 to 40 mm; and the length of the third metal sheet ranges from 5 to 30 mm.

[0023] The technical advantages of this application are as follows: By axially arranging multiple support members with different stiffnesses within the bendable segment, the distal end of the bendable segment has high flexibility, which can reduce damage to the blood vessel wall or other tissues, while facilitating bending control; the middle section of the bendable segment has moderate support performance, ensuring that the middle electrode can effectively adhere to the curved physiological structure, improving the accuracy of signal acquisition, while the moderate stiffness will not lead to insufficient electrode-tissue contact, nor will it damage the tissue due to excessive stiffness; the proximal end of the bendable segment has strong support force, which not only ensures the overall structural stability and operational controllability of the catheter, but also eliminates the need for the operator to rotate the catheter when pushing it, improving the convenience of operation. Attached Figure Description

[0024] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0025] Figure 1 This is a schematic diagram of the structure of a controllable bending calibration tube provided in one embodiment of this application;

[0026] Figure 2 This is a schematic diagram of the structure of a support member provided in an embodiment of this application;

[0027] Figure 3 This is a schematic cross-sectional view of a bendable segment provided in an embodiment of this application;

[0028] Figure 4 This is a schematic diagram of the fixing method of the support member provided in one embodiment of this application;

[0029] Figure 5 This is a schematic diagram of the structure of a wire positioning component provided on a bending control line according to an embodiment of this application;

[0030] Figure 6This is a schematic diagram of the structure of a pull-wire positioning component provided in one embodiment of this application;

[0031] Figure 7 This is a schematic diagram of the tip structure of a catheter provided in one embodiment of this application.

[0032] Figure 8 This is a schematic diagram of the head end structure of a catheter in the prior art.

[0033] Explanation of icon numbers:

[0034] 10. Catheter body; 11. Bendable section; 111. Channel; 112. First cavity; 113. Second cavity; 114. Gap; 12. Main body section; 121. Inner tube; 13. Bending control handle; 14. Bending mark section; 15. Tip;

[0035] 20. Support component; 21. First metal sheet; 22. Second metal sheet; 23. Third metal sheet;

[0036] 30. Electrode; 40. Electrode lead; 50. Bending control wire; 60. Retaining ring;

[0037] 70. Pull-out positioning component; 71. Spring ring; 72. Heat shrink tubing. Detailed Implementation

[0038] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application can also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0039] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the specific implementation methods of this application will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without creative effort.

[0040] To keep the drawings concise, each drawing only schematically shows the parts relevant to this application, and they do not represent the actual structure of the product. Furthermore, for ease of understanding, in some drawings, only one of the components with the same structure or function is schematically shown, or only one is labeled. In this document, "one" not only means "only one," but can also mean "more than one."

[0041] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0042] In this document, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linkage" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; or they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0043] In the embodiments shown in the accompanying drawings, the directional indications (such as up, down, left, right, front, and back) are relative rather than absolute when describing the structure and movement of the various components, and are not intended to limit the direction of the product during actual use.

[0044] Furthermore, in the description of this application, ordinal numbers, such as "first" and "second," are used only to distinguish related objects and should not be construed as indicating or implying the relative importance or order between related objects.

[0045] In this application, the terms "proximal" and "distal" refer to the relative orientation, position, and direction of elements or movements relative to each other from the perspective of a physician using the medical device. Although "proximal" and "distal" are not restrictive, "proximal" generally refers to the end of the medical device that is closer to the physician during normal operation, while "distal" generally refers to the end that first enters the patient's body.

[0046] In existing mapping catheter technologies, the flexible section of the catheter is typically designed with low stiffness to facilitate flexible bending operations. However, this design has significant drawbacks in practical applications. When the mapping catheter is inserted into the body, the low stiffness of the flexible section results in insufficient support, requiring the operator to continuously rotate and push the catheter during delivery to ensure its smooth entry into the target site. This greatly increases the complexity and difficulty of the operation, causing significant inconvenience to clinical procedures. Furthermore, the electrodes on the flexible section are prone to deformation during operation due to the low stiffness. This deformation prevents the electrodes from fully adhering to the target tissue surface. Insufficient electrode-tissue contact directly affects the accuracy of signal acquisition, thereby impacting diagnostic and therapeutic outcomes.

[0047] To address this, this disclosure provides a controllable bending calibration tube, such as... Figures 1 to 3As shown, by setting a support member 20 within the bendable segment 11, the support member 20 is formed by multiple segments with different stiffnesses, giving the bendable segment 11 multiple stiffnesses along its length. This design gives the distal end of the bendable segment 11 good flexibility, allowing for better compliance of the catheter during intravenous advancement. It can adjust the distal position as the blood vessel travels, avoiding catheter damage to tissues and improving the bend control and advancement safety of the bendable segment 11. A medium-length metal plate is added to the middle section of the bendable segment 11 to improve its support. Appropriate support performance ensures that the electrode 30 in the middle of the bendable segment 11 can effectively adhere to the curved tubular vein, improving the accuracy of signal acquisition and thus enhancing diagnostic and treatment outcomes. A shorter metal plate is further added to the proximal end of the bendable segment 11, providing strong support and effective propulsion force. This allows for effective propulsion during catheter advancement, enabling the catheter to be smoothly advanced into place without twisting after entering the coronary sinus ostium, reducing the difficulty of clinical operation.

[0048] In one specific embodiment, such as Figures 1 to 3 As shown, the controllable bending calibration catheter includes a catheter body 10 and a support member 20. The catheter body 10 includes a bendable section 11, and a channel 111 extending axially within the bendable section 11. The support member 20 is fixedly disposed within the channel 111 and extends axially along the channel 111. The support member 20 includes at least three support segments, and the stiffness of the at least three support segments increases axially from the distal end to the proximal end, so that the bendable section 11 forms multiple stiffness segments axially.

[0049] Specifically, the bendable section 11 of the catheter body 10 can be a single-layer structure composed of common medical polymer materials such as polyurethane and PEBAX. Within this single-layer structure, a channel 111 extending axially is formed. A support member 20 is fixedly installed within the channel 111. The length direction of the support member 20 extends axially along the catheter body 10. The support member 20 includes at least three support segments to form a multi-segment stiffness with increasing stiffness from the distal to the proximal end along the axial direction. The following explanation uses a three-segment support as an example. Figure 2 As shown, the support member 20 includes a first support segment c1, a second support segment c2, and a third support segment c3 arranged sequentially from the distal end to the proximal end along the axial direction. The stiffness of the first support segment c1, the second support segment c2, and the third support segment c3 gradually increases. The first support segment c1 has lower stiffness and better flexibility, which facilitates bending control. The second support segment c2 (middle section) has moderate stiffness, which can improve the support in the middle and ensure effective contact of the electrode in the middle of the bendable segment 11. The third support segment c3 (proximal section) has greater stiffness, which can further improve the support force and thus provide effective propulsion force when pushing the catheter, so that the catheter can be pushed into place without twisting after entering the coronary sinus ostium.

[0050] This embodiment incorporates multiple support members 20 with varying stiffness within the bendable section 11. This design ensures high flexibility at the distal end of the bendable section 11, reducing damage to the vessel wall or other tissues and facilitating bending control. The middle section of the bendable section 11 provides adequate support, ensuring effective contact of the central electrode 30 within the curved physiological structure, thereby improving signal acquisition accuracy. The moderate stiffness prevents insufficient contact between the electrode 30 and the tissue, while also avoiding tissue damage due to excessive rigidity. The proximal end of the bendable section 11 provides strong support, ensuring not only the overall structural stability and operational controllability of the catheter but also eliminating the need for rotation during catheter insertion, thus enhancing operational convenience.

[0051] In some embodiments, the support member 20 includes at least three layers of metal sheets, which are stacked sequentially in a direction perpendicular to the axial direction of the channel 111, and the length of the at least three layers of metal sheets gradually decreases along the stacking direction. The proximal end of the support member 20 is approximately flush, and the distal end forms multiple steps, so that the bendable section 11 forms at least three support sections with different stiffnesses along the axial direction.

[0052] The support member 20 is formed by stacking at least three layers of metal sheets, which can be made of conventional materials such as nitinol or stainless steel. The support member 20 can have three, four, or more layers, with these metal sheets of different lengths, forming multiple segments of different stiffness after stacking. In this embodiment, the specific number of layers of the support member can be set according to the required number of stiffness segments. For example, when the bendable segment 11 needs to achieve three stiffness segments, the support member 20 can be formed by stacking three layers of metal sheets of different lengths; when the bendable segment 11 needs to achieve four stiffness segments, the support member 20 can be formed by stacking four layers of metal sheets of different lengths, and so on. This embodiment does not limit the specific number of layers of the support member 20. The following explanation uses the example of the support member 20 consisting of three layers of metal sheets of different lengths.

[0053] For example, such as Figure 2 As shown, the support member 20 includes a first metal sheet 21, a second metal sheet 22, and a third metal sheet 23. The first metal sheet 21, the second metal sheet 22, and the third metal sheet 23 are stacked sequentially along a direction perpendicular to the axial direction of the channel 111, with their lengths decreasing sequentially. That is, the first metal sheet 21 is the longest, the third metal sheet 23 is the shortest, and the length of the second metal sheet 22 is between that of the first metal sheet 21 and the second metal sheet 22. The proximal ends of the stacked first metal sheet 21, the second metal sheet 22, and the third metal sheet 23 are approximately flush, while the distal ends form multiple steps, causing the bendable section 11 to form three segments with progressively increasing stiffness along its distal to proximal direction. The distal end of the bendable section 11 is... Figure 1The a-end of the bendable segment 11 is supported by the support member 20, which forms three segments with different stiffnesses along the axial direction. These three segments are the first segment, the second segment, and the third segment along the direction from the distal end to the proximal end of the bendable segment 11. The first segment (distal segment) is supported only by the first metal plate 21, with low stiffness and good flexibility, which facilitates bending control. The second segment (middle segment) is supported by the first metal plate 21 and the second metal plate 22, with moderate stiffness, which can improve the support in the middle and ensure the effective contact of the electrode in the middle of the bendable segment 11. The third segment (proximal segment) is supported by the first metal plate 21, the second metal plate 22, and the third metal plate 23, with high stiffness, which can further improve the support force and thus provide effective propulsion force when pushing the catheter, so that the catheter can be pushed into place without twisting after entering the coronary sinus ostium.

[0054] In this embodiment, the length of the first metal sheet 21 ranges from 40 to 200 mm; the length of the second metal sheet 22 ranges from 15 to 40 mm; and the length of the third metal sheet 23 ranges from 5 to 30 mm. In practical applications, different lengths can be selected according to the different bending widths of the bendable section 11. Taking the commonly used D-bend in clinical practice as an example, the preferred length range of the first metal sheet 21 is 65 to 70 mm, the preferred length range of the second metal sheet 22 is 22 to 27 mm, and the preferred length range of the third metal sheet 23 is 15 to 20 mm.

[0055] In some embodiments, the support member 20 includes at least three integrally formed support segments of different thicknesses. By changing the thickness of the support segments, the stiffness of the support segments can be changed. For example, the support member 20 includes a first support segment c1, a second support segment c2, and a third support segment c3. The thickness of the first support segment c1, the second support segment c2, and the third support segment c3 increases from the distal end to the proximal end, so as to achieve an increasing stiffness of the first support segment c1, the second support segment c2, and the third support segment c3.

[0056] In some embodiments, such as Figure 1As shown, the controllable bending mapping catheter also includes at least two electrodes 30, which are arranged along the axial direction of the bendable section 11 with different electrode spacings. The shape of the electrodes 30 can be a ring electrode, a point electrode, or a spiral electrode, etc.; for example, a ring electrode can provide a 360-degree signal acquisition range, while a point electrode can more accurately locate specific tissue areas. The materials of the electrodes 30 are usually selected from metals with good biocompatibility and high conductivity, such as platinum, iridium, or their alloys. These metals can not only accurately conduct electrical signals, but also do not cause adverse reactions when used in the human body. Different electrode spacings can be adjusted as needed. In areas requiring high-resolution mapping, the electrode spacing can be set smaller to acquire electrophysiological signals more meticulously, thereby more accurately locating the origin of abnormal electrical signals; while in some preliminary screening areas or areas where high resolution is not required, the electrode spacing can be appropriately increased to reduce the number of electrodes. The number of electrodes 30 can be flexibly set according to actual needs. In some simple examinations or mapping tasks, the number of electrodes 30 can be reduced to reduce costs and operational complexity; while in complex cases, the number of electrodes 30 can be increased to obtain more comprehensive electrophysiological information.

[0057] like Figure 3 As shown, the controllable bending calibration catheter also includes an electrode wire 40 and a bending control wire 50. The support member 20 divides the channel 111 into a first cavity 112 and a second cavity 113. The electrode wire 40 passes through the first cavity 112 and its distal end is electrically connected to the electrode 30. The bending control wire 50 passes through the second cavity 113 and its distal end is fixedly connected to the distal end of the support member 20.

[0058] Electrode 30 is connected to an external mapping system via electrode leads 40. These electrode leads 40 are integrated inside the catheter body 10 to prevent them from being exposed externally and thus susceptible to interference or damage. The material of the electrode leads 40 also needs to have good conductivity and anti-interference capabilities to ensure that electrical signals can be transmitted to the mapping system accurately.

[0059] The bending control line 50 is fixedly connected to the distal end of the support member 20. The operator can control the bending direction and angle of the bendable section 11 by manipulating the bending control line 50. The bending control line 50 has good flexibility and tensile strength, which allows the bendable section 11 of the conduit body 10 to bend flexibly when the operator applies external force, without breaking or deforming.

[0060] In some embodiments, such as Figure 4As shown, the controllable bending measuring guide also includes a fixing ring 60, which is fixedly disposed at the distal end within the channel 111. The distal ends of the support member 20 and the bending control line 50 are respectively fixedly connected to the fixing ring 60. The support member 20 and the bending control line 50 can be fixed together with the fixing ring by resistance welding or soldering. The fixing ring 60 is fixed within the channel 111 and located at the distal end of the bendable section 11 by adhesive or welding to form a stable structure, ensuring that the distal end of the bendable section 11 maintains its integrity during the bending process, preventing relative displacement or loosening between the support member 20 and the bending control line 50. During bending, the bending control line 50 is pulled, thereby causing the entire head (distal end) of the bendable section 11 to move along the bending direction of the bending control line 11.

[0061] In some embodiments, such as Figure 1 As shown, the catheter body 10 also includes a main body segment 12 and a bending control handle 13. The distal end of the main body segment 12 is connected to the proximal end of the bendable segment 11. The bending control handle 13 is located at the proximal end of the main body segment 12 and is fixedly connected to the bending control line 50.

[0062] The main body segment 12 can be a single-layer or double-layer structure, depending on the design requirements of the conduit. When the main body segment 12 is a single-layer structure, it is integrally formed with the bendable segment 11, and the interior of the main body segment 12 communicates with the channel 111 inside the bendable segment 11 to accommodate the electrode wire 40 and the bending control wire 50. The proximal end of the support member 20 is fixedly connected to the inner wall of the main body segment 12. When the main body segment 12 is a double-layer structure, the outer tube of the main body segment 12 is integrally formed with the bendable segment 11, and the inner tube 121 of the main body segment 12 is fixedly installed inside the outer tube of the main body segment 12. Figure 4 As shown, the near end of the support member 20 is fixedly connected to the inner tube 121 of the main body section 12, and the electrode wire 40 and the bending control wire 50 are inserted inside the inner tube 121 of the main body section 12. The inner tube 121 of the main body section 12 can be a spring coil.

[0063] The bending control handle 13 is located at the proximal end of the main body section 12, and the proximal end of the bending control line 50 is fixed to the bending control handle 13. The bending control handle 13 typically includes a housing and a control mechanism located inside the housing. The control mechanism can be a simple pull ring or push rod, or it can be a complex joystick or knob. The operator controls the bending of the bendable section 11 by manipulating the bending control handle 13.

[0064] Furthermore, such as Figure 1 As shown, a bending mark section 14 is also provided between the proximal end of the main body section 12 and the bending control handle 13. The bending mark section 14 is used to display the bending shape when the bendable section 11 is controlled to bend.

[0065] In some embodiments, such as Figure 3 and Figure 5As shown, at least two wire positioning members 70 are provided axially spaced on the bending control line 50. The wire positioning members 70 are assembled on the outside of the bending control line 50, and their function is to increase the overall stability of the bending control line 50, and ensure that the bending control line 50 is always inside the bending arc of the support member 20 during the bending process, so as to ensure the stability and smoothness of the entire bending control system.

[0066] like Figure 3 and Figure 5 As shown, the support member 20 is connected to the inner wall of the bendable section 11 only at both ends along the length direction. The support member 20 has gaps 114 between its two sides along the width direction and the inner wall of the channel 111, facilitating controlled bending of the bendable section 11. A pull-line positioning member 70 is provided on the bending control line 50. The outer diameter of the pull-line positioning member 70 is larger than the width of the gap 114, ensuring that the bending control line 50 remains within the second cavity 113 during the bending process. This ensures the stability and smoothness of the entire bending control system, improves the stability of the bending control line 50 within the second cavity 113, and thus enhances the overall bending stability of the bendable section 11. Simultaneously, it prevents the bending control line 50 from entering the first cavity 112 and interfering with the normal operation of the electrode wire 40, improving signal transmission stability. In this embodiment, the pull-line positioning member 70 needs to be a hollow short tube with a certain degree of flexibility to ensure that the pull-line positioning member 70 can deform along with the bending control line 50 during the bending of the conduit, without affecting the overall bending shape of the conduit.

[0067] The drawbar positioning element 70 is designed as a hollow short tube with a certain degree of flexibility and is assembled on the outside of the bending control line 50. In one embodiment, such as Figure 6 As shown, the wire positioning component 70 includes a spring coil 71 and a heat shrink tubing 72. The spring coil 71 is sleeved on the bending control wire 50, and both ends of the spring coil 71 are fixedly connected to the bending control wire 50 via the heat shrink tubing 72. The spring coil 71 is an ultra-soft spring coil with an insulating coating. The material of the spring coil 71 is metal, the diameter of a single spring wire of the spring coil 71 ranges from 0.05 to 0.2 mm, and the outer diameter of the entire spring coil 71 ranges from 0.2 to 0.6 mm. In this embodiment, both ends of the spring coil 71 can be fixedly connected to the bending control wire 50 via the heat shrink tubing 72.

[0068] In another embodiment, the drawstring positioning component 70 includes a heat-shrink tubing. The heat-shrink tubing is fixedly sleeved on the outside of the bending control line 50 by a heat-shrinking process. The heat-shrink tubing with a larger outer diameter is provided on the outside of the bending control line 50, which also improves the overall stability of the bending control line 50, preventing it from entering the first cavity 112 from the second cavity 113. In this embodiment, the drawstring positioning component 70 can be a short section of heat-shrink tubing. The material of the heat-shrink tubing can be PET or PTFE. The heat-shrink tubing is fixed to the bending control line 50 by heat shrinking, and the outer diameter of the heat-shrink tubing ranges from 0.2 to 0.6 mm.

[0069] In some embodiments, such as Figure 7As shown, the distal end of the bendable segment 11 is formed into a circular head end 15 by self-heating and melting.

[0070] The distal end of the bendable section 11 is the tip 15 of the entire catheter. In the prior art, the tip 15 of the catheter is designed with various structures, such as... Figure 8 As shown, the first design is a head electrode design, where the tip 15 of the catheter directly serves as the electrode 30. The advantage of this design is that it can collect electrical signals from deeper sites. The disadvantage is that head electrodes are typically made of metal, which has high hardness and may damage tissue during operation, thus reducing safety. The second design is a spherical adhesive design, where a circular tip 15 is formed at the distal end of the catheter using adhesive and UV curing. Its advantage is that compared to the head electrode design, the hardness of the tip 15 is reduced, thus improving safety. However, the disadvantage is that to ensure the adhesive bonding strength, a relatively long catheter length is required at the distal end, resulting in a greater distance between the electrode on the bendable section 11 and the catheter tip 15. If the same signal needs to be measured at the same location, the catheter needs to be inserted deeper, which may cause inconvenience in some operations.

[0071] In this embodiment, in order to shorten the length of the catheter tip 15 and reduce the rigidity of the catheter tip 15, such as... Figure 7 As shown, the distal end of the entire catheter (flexible section) is heated and melted to form a circular tip 15. The circular tip 15 is made by directly melting the material of the flexible section itself, and its hardness is consistent with that of the flexible section 11 itself. This design reduces the hardness of the tip 15 while shortening the reserved length of the catheter tip 15 as much as possible, thereby improving the overall mapping effectiveness of the catheter.

[0072] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0073] It should be noted that the above embodiments can be freely combined as needed. The above description is only a preferred embodiment of this application. It should be pointed out that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the protection scope of this application.

Claims

1. A controllable bending calibration tube, characterized in that, include: The catheter body includes a bendable section, wherein the bendable section has a channel extending along its axial direction; A support member is fixedly disposed within the channel and extends along the axial direction of the channel. The support member includes at least three support segments, the stiffness of which increases from the distal end to the proximal end along the axial direction, so that the bendable segment forms multiple stiffness segments along the axial direction.

2. The controllable bending measuring tube according to claim 1, characterized in that, The at least three support segments include at least three layers of metal sheets, which are stacked sequentially in a direction perpendicular to the axial direction of the channel. The length of the at least three layers of metal sheets gradually decreases along the stacking direction. The proximal end of the support is approximately flush with the distal end, which forms multiple steps.

3. The controllable bending measuring tube according to claim 1, characterized in that, It also includes at least two electrodes, which are spaced apart along the axial direction of the bendable section.

4. The controllable bending measuring tube according to claim 3, characterized in that, It also includes electrode wires and bending control wires. The support member divides the channel into a first cavity and a second cavity. The electrode wires pass through the first cavity and are electrically connected to the electrode at their distal ends. The bending control line passes through the second cavity and its distal end is fixedly connected to the distal end of the support member.

5. The controllable bending measuring tube according to claim 4, characterized in that, It also includes a fixing ring, which is fixedly disposed at the far end of the channel, and the far end of the support member and the far end of the control line are respectively fixedly connected to the fixing ring.

6. The controllable bending measuring tube according to claim 4, characterized in that, The catheter body also includes a main body segment and a bending control handle. The distal end of the main body segment is connected to the proximal end of the bendable segment. The bending control handle is located at the proximal end of the main body segment and is fixedly connected to the bending control line.

7. The controllable bending measuring tube according to claim 4, characterized in that, At least two wire positioning elements are provided at axial intervals along the bending control line.

8. The controllable bending measuring tube according to claim 7, characterized in that, The pull-line positioning component includes a spring coil and a heat shrink tubing. The spring coil is sleeved on the control bending line, and both ends of the spring coil are fixedly connected to the control bending line through the heat shrink tubing; or; The pull-line positioning component includes a heat-shrink tubing, which is fixedly sleeved onto the control bend line by a heat-shrink process.

9. A controllable bending measuring tube according to claim 7, characterized in that, The support member has gaps between its two sides along its width direction and the inner wall of the channel, and the outer diameter of the pull-wire positioning member is larger than the width of the gaps.

10. A controllable bending calibration tube according to any one of claims 1-9, characterized in that, The distal end of the bendable section is formed into a circular head by self-heating and melting.

11. A controllable bending calibration tube according to any one of claims 1-9, characterized in that, The support includes a first metal sheet, a second metal sheet, and a third metal sheet. The first metal sheet, the second metal sheet, and the third metal sheet are stacked sequentially in a direction perpendicular to the axial direction of the channel, and their lengths decrease sequentially. The proximal ends of the stacked first metal sheet, the second metal sheet, and the third metal sheet are approximately flush, and multiple steps are formed at the distal ends, so that the bendable section forms three segments with progressively increasing stiffness from its distal end to its proximal end.

12. The controllable bending calibration tube according to claim 11, characterized in that, The length of the first metal sheet ranges from 40 to 200 mm; the length of the second metal sheet ranges from 15 to 40 mm; and the length of the third metal sheet ranges from 5 to 30 mm.

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