ablation catheter

Abstract

This invention provides an ablation catheter, relating to the field of medical device technology. The ablation catheter includes a catheter body and an ablation component. The ablation component is connected to the catheter body and includes a support frame and ablation elements disposed on the support frame. The support frame includes multiple support elements. The ablation component can switch between a contracted state and an expanded state, causing the multiple support elements to converge radially inward or expand radially outward relative to the axis of the support frame. This allows the support frame to switch to the desired point or ring shape for ablation, thereby enabling the ablation catheter to achieve ring, point, or linear ablation according to actual needs, quickly and accurately ablate lesions, achieve better ablation effects, improve the flexibility of the ablation catheter, and significantly reduce costs.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to an ablation catheter. Background Technology

[0002] Atrial fibrillation (AF) is a common and persistent cardiac arrhythmia. Tissue ablation is commonly used to treat various arrhythmias, including atrial fibrillation. To treat arrhythmias, an ablation catheter can be used to ablate a target tissue area to stop the propagation of abnormal electricity and / or disrupt abnormal electrical conduction through the heart tissue, thereby achieving the therapeutic goal. The target tissue area can be a point, a complete line, or a complete closed loop.

[0003] However, in current practice, although point ablation catheters can ablate point by point to form a line or a closed loop, they are prone to incomplete ablation between two points, resulting in many problems such as long operation time, inconvenience of use, and high cost. While some complex ablation catheters can ablate a closed loop, they cannot flexibly achieve point ablation. Using multiple ablation catheters to achieve point, line, or ring ablation will undoubtedly greatly increase costs. Summary of the Invention

[0004] Therefore, it is necessary to provide an ablation catheter that can perform ring-shaped, point-shaped, or linear ablation according to actual needs, and quickly and accurately ablate lesions.

[0005] This invention provides an ablation catheter, comprising:

[0006] Catheter body;

[0007] An ablation assembly is disposed at the distal end of the catheter body. The ablation assembly includes a support frame and at least one ablation element disposed on the support frame. The support frame includes a plurality of support elements, which are arranged circumferentially around the axis of the support frame. The proximal and distal ends of the support elements are spaced apart in the radial direction of the support frame.

[0008] The support frame is capable of switching between a contracted state and an expanded state. When the support frame switches to the contracted state, the plurality of support members converge radially inward relative to the axis of the support frame. When the support frame switches to the expanded state, the plurality of support members expand radially outward relative to the axis of the support frame.

[0009] As can be seen from the above technical solution, the present invention has at least the following advantages and positive effects: The ablation catheter of the present invention can ablate the target ablation area through a shrinkable or expandable support frame and ablation elements disposed on the support frame; the support frame includes multiple support elements, the proximal and distal ends of the support elements are spaced apart radially in the support frame, and the multiple support elements can be radially converged inward or radially expanded outward to allow the support frame to switch to the desired point or ring shape for ablation, thereby enabling the ablation catheter to achieve ring, point or linear ablation according to actual needs, quickly and accurately ablate the lesion tissue, achieve better ablation effect, improve the flexibility of the ablation catheter, and greatly save costs. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the ablation catheter when the supporting skeleton is in an expanded state according to an embodiment of the present invention;

[0011] Figure 2 for Figure 1 The front view;

[0012] Figure 3 for Figure 1 A top view of

[0013] Figure 4 This is a schematic diagram of the ablation catheter when the supporting skeleton is in a contracted state according to one embodiment of the present invention;

[0014] Figure 5 for Figure 4 A top view of

[0015] Figure 6 This is a schematic diagram of the ablation catheter when the supporting skeleton is in a contracted state, according to another embodiment of the present invention;

[0016] Figure 7 This is a schematic diagram of the ablation catheter when the supporting skeleton is in an expanded state, according to another embodiment of the present invention.

[0017] The attached diagram lists the components represented by each number as follows:

[0018] 1. Ablation catheter;

[0019] 10. Catheter body; 100. First axial lumen; 110. Second axial lumen;

[0020] 20. Support component; 200. First arm; 210. Second arm; 220. Bearing arm; 230. Channel; 21. Ablation component; 22. Ablation assembly; 23. Support frame; 24. Movable hole;

[0021] 30. Driving components; 31. Linkage components. Detailed Implementation

[0022] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the specific details described below are only a part of the embodiments of the present invention, and the present invention can be implemented in many other embodiments different from those described herein. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0023] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0025] In the description of this invention, "proximal end" refers to the end closer to the operator during surgery, and "distal end" refers to the end farther from the operator during surgery. Axial direction refers to the direction of the central axis of the device, and radial direction is the direction perpendicular to the central axis. This definition is for convenience only and should not be construed as a limitation of the invention.

[0026] The ablation catheter provided in this invention is used to ablate a target ablation area using pulsed ablation, radiofrequency ablation, or any other suitable form of ablation energy to achieve electrical isolation. It is delivered to the target ablation area percutaneously via a delivery device (sheath). The target ablation area can be located in the heart, including but not limited to pulmonary veins, or in areas with typical atrial flutter or triggering foci not originating from pulmonary veins (such as the left atrial appendage, superior vena cava, or coronary sinus ostium). It is understood that the target ablation area is not limited to the heart and can also be located in other body tissues; this is not limited here.

[0027] Example 1, see Figures 1 to 5 The structure shown.

[0028] See also Figures 1 to 5 The present invention provides an ablation catheter 1, which includes a catheter body 10 and an ablation component 22. The ablation component 22 includes a support frame 23 and at least one ablation element 21 disposed on the support frame 23.

[0029] Specifically, the catheter body 10 is a tubular structure. It is understood that the catheter body 10 can also be of any suitable construction and can be made of any suitable material. One construction includes an outer wall made of a polymeric material such as polyurethane or PEBAX (polyether-block-amide). The catheter body 10 has a degree of flexibility, enabling it to bend radially to adapt to the curved structures within the heart.

[0030] The support frame 23 is located at the distal end of the catheter body 10. The support frame 23 is elastic and can be retracted into the delivery device so that the support frame 23 can easily pass through the delivery device. When the target ablation area is reached by the delivery device, both the distal and proximal ends of the support frame 23 can be exposed from the distal end of the delivery device.

[0031] The support frame 23 can be made by cutting elastic metal tubing, weaving elastic metal wire, or a combination of partial weaving and partial tubing cutting. Different parts can be welded or fixed together with connectors. The tubing material can be metal or non-metal, preferably shape memory metal or nickel-titanium alloy. In this embodiment, the support frame 23 can be cut and shaped from a single nickel-titanium alloy tubing.

[0032] See also Figure 1 , Figure 2 and Figure 4 The support frame 23 includes multiple support members 20, which are arranged circumferentially around the axis of the conduit body 10. Each support member 20 is a screw-type structure, and its cross-sectional shape can be circular, semi-circular, bulging, or other shapes, without specific limitation. The proximal and distal ends of the support members 20 are spaced apart radially from each other in the support frame 23. The number of support members 20 used in the support frame 23 can be two, three, four, five, six, seven, eight, or any other suitable number. The support members 20 can be uniformly or non-uniformly distributed circumferentially.

[0033] The support frame 23 can switch between a contracted state and an expanded state. When the support frame 23 switches to the expanded state, the multiple support members 20 open radially outward relative to the axis of the support frame 23, and the radial dimension of the support frame 23 increases. When the support frame 23 switches to the contracted state, the multiple support members 20 converge radially inward relative to the axis of the support frame 23, and the radial dimension of the support frame 23 decreases.

[0034] The ablation element 21 is disposed on the support 20. When the distal end of the support 20 is attached to the inner wall of the tissue inside the heart, the ablation element 21 can be used to provide ablation energy to perform tissue ablation. The ablation element 21 can also be used for electrophysiological signal mapping, thereby realizing other functions such as cardiac mapping.

[0035] In some embodiments, the ablation element 21 can be an ablation electrode, and the material of the ablation electrode can be medical metals such as platinum, iridium, gold, and silver that can be used for interventional therapy. Figure 1 As shown, the ablation element 21 is an ablation electrode, and it is a ring-shaped electrode. It is understood that the ablation electrode can be a ring-shaped electrode, a sheet-like electrode, a point-like electrode, or a spherical electrode, etc., and this embodiment does not impose a specific limitation. The ablation electrode can be used for both ablation and electrophysiological signal mapping. For example, in one time period, all ablation electrodes are used for ablation, and in another time period, all are used for mapping; or some ablation electrodes are always used for ablation, and some are always used for mapping. In some embodiments, the ablation electrode can be used to perform other functions such as cardiac pacing. The number of ablation electrodes can be one or more. When the number of ablation electrodes is one, the ablation electrode can be disposed on any one of the support elements 20. When there are multiple ablation electrodes, the multiple ablation electrodes can be set on the same support 20, or they can be set on some of the support 20 respectively, or each support 20 can be set with ablation electrodes. For example, each support 20 can be set with at least three ablation electrodes. The ablation electrodes can be evenly distributed along the support 20 to facilitate the acquisition of ablation or electrophysiological signals.

[0036] In some embodiments, a portion of the support member 20 may also be used as the ablation element 21. Specifically, the support member 20 is made of a conductive metal material, the exposed portion of the support member 20 serves as the ablation element 21, and the remaining portion is provided with an insulating layer. The support member 20 conducts an electrical signal to ablate the exposed portion. For example, an insulating coating may be formed on the surface of a nickel-titanium wire by vacuum deposition, and the portion of the nickel-titanium wire surface without the insulating coating serves as the ablation element 21.

[0037] The ablation energy in this embodiment can be pulse, radio frequency, microwave, etc., and is not specifically limited here.

[0038] In the embodiment employing radio frequency ablation, the exposed portion of the support member 20 serves as the ablation element 21, and the support member 20 conducts electrical signals to perform ablation. The surface of the support member 20, except for the ablation element 21, undergoes vacuum coating.

[0039] In the embodiment employing pulsed ablation, the ablation element 21 is an ablation electrode, which is disposed on the support element 20. Each ablation electrode has an insulating wire welded to its inner wall. The support element 20 includes a rod and an insulating sleeve fitted over the rod. The insulating sleeve is made of PEBAX tubing or other polymer insulating materials, ensuring insulation between the ablation electrode and the rod. The insulating sleeve can be one, two, or multiple layers, and is not limited here. The cross-sectional shape of the rod can be circular, semi-circular, convex, or other shapes, and is not limited here. In this embodiment, the rod is made of nickel-titanium wire, giving it excellent elasticity and strength, allowing it to adhere well to the target tissue. It is understood that the rod can also be made of other materials, such as stainless steel or polymer materials. The ablation electrode is fitted onto an insulating sleeve, ensuring insulation between the ablation electrode and the rod. An insulating wire is placed between the rod and the insulating sleeve or other polymer material. That is, an insulating wire passes through the surface of the insulating sleeve through the inner surface of each ablation electrode and connects to the ablation electrode connector on the handle connected to the conduit body 10 along the rod. The ablation electrode connector is electrically connected to an external pulse signal source. The ablation electrode and the wire are connected by welding or other special processes.

[0040] In one embodiment, the voltage range of the pulse signal received by the ablation electrode is 500V to 2400V, including all values ​​and sub-ranges therebetween, and the pulse frequency is 1kHz to 500kHz, including all values ​​and sub-ranges therebetween. The pulse energy can be a unipolar high-voltage pulse power supply or a bipolar high-voltage pulse power supply. The energy pulse received by the ablation electrode includes single-phase pulses or biphase pulses, and each ablation electrode can be configured with single-phase or biphase pulses with different parameters such as voltage, pulse width, repetition frequency, duty cycle, and number of pulses.

[0041] During the process of switching the support frame 23 to the expansion state, the multiple support members 20 expand radially outward relative to the axis of the support frame 23, and the radial dimension of the support frame 23 increases. At this time, the support frame 23 has the shape of an annular opening, which can be used for annular ablation. For example, the ablation member 21 on the support frame 23 can be used to perform annular ablation on the pulmonary vein opening. During the process of switching the support frame 23 to the contraction state, the multiple support members 20 converge radially inward relative to the axis of the support frame 23, and the radial dimension of the support frame 23 decreases. The entire support frame 23 can be regarded as a point to achieve targeted point ablation or point-by-point line ablation. For example, point ablation (focal ablation) or point-by-point line ablation can be performed on the inside of the heart (such as the mitral isthmus, tricuspid isthmus, and left atrial roof).

[0042] In this embodiment, the radial dimension of the support frame 23 can be flexibly adjusted, allowing the support frame 23 to achieve point, linear, or annular ablation using the ablation element 21 under any appropriate radial dimension according to actual needs. This enables rapid and precise ablation of lesions, resulting in better ablation effects. Furthermore, this embodiment can achieve point, linear, or annular ablation using a single ablation catheter, making the ablation catheter more flexible and significantly reducing costs.

[0043] The aforementioned multiple support members 20 can be radially converged inward or radially expanded outward relative to the axis of the support frame 23 through various movement methods, so that the support frame 23 can switch between a contracted state and an expanded state.

[0044] In one embodiment, the support member 20 is slidably connected to the catheter body 10 by means of interpenetration and sliding, so that the support frame 23 switches between a contracted state and an expanded state. In this embodiment, multiple support members 20 are movably interpenetrated in the catheter body 10, and the proximal ends of the multiple support members 20 converge and connect together at the proximal end of the catheter body 10, and are connected to a handle (not shown in the figure) connected to the catheter body 10, so as to control the sliding of the multiple support members 20 in the catheter body 10 by means of the handle.

[0045] Specifically, the catheter body 10 has an axial inner cavity along its axial direction, and multiple support members 20 are movably inserted into the axial inner cavity. As the multiple support members 20 move proximally relative to the catheter body 10 along the axial inner cavity, they radially converge inward and longitudinally retract relative to the axis of the support frame 23, causing the support frame 23 to switch to a contracted state and its radial dimension to decrease. Conversely, as the multiple support members 20 move distally relative to the catheter body 10 along the axial inner cavity, they radially expand outward relative to the axis of the support frame 23, causing the support frame 23 to switch to an expanded state and its radial dimension to increase.

[0046] Please refer to Figures 1 to 5 In some embodiments, the support member 20 includes a first arm 200, a second arm 210, and a bearing arm 220. The first arm 200 and the second arm 210 are spaced apart, and the first arm 200, the second arm 210, and the bearing arm 220 form a hollow hole by surrounding the distal end face of the catheter body 10. The two ends of the bearing arm 220 are respectively connected to the distal ends of the first arm 200 and the second arm 210, and at least one of the first arm 200 and the second arm 210 is movably inserted into the axial cavity. At least one of the first arm 200 and the second arm 210 can move proximally or distally relative to the catheter body 10 along the axial cavity, so that the plurality of support members 20 converge radially inward or expand radially outward relative to the axis of the support frame 23.

[0047] In one feasible embodiment, the first arm 200 is fixedly connected to the catheter body 10 by welding or as an integrally formed structure, and the second arm 210 is movably inserted into the axial inner cavity. The operator can control the second arm 210 of each support member 20 to move axially relative to the catheter body 10 along the axial inner cavity, thereby adjusting the radial inward convergence or radial outward expansion of the multiple support members 20 relative to the axis of the support frame 23. Similarly, in one feasible embodiment, the second arm 210 can also be fixedly connected to the catheter body 10 by welding or as an integrally formed structure, with the first arm 200 movably inserted into the axial inner cavity. The operator can then control the first arm 200 of each support member 20 to move axially relative to the catheter body 10 along the axial inner cavity, thereby adjusting the radial inward convergence or radial outward expansion of the multiple support members 20 relative to the axis of the support frame 23.

[0048] In another feasible embodiment, both the first arm 200 and the second arm 210 are movably inserted into the axial inner cavity of the catheter body 10. The operator can control either the first arm 200 or the second arm 210 of each support member 20, or simultaneously control the first arm 200 and the second arm 210 to move axially relative to the catheter body 10 along the axial inner cavity, thereby adjusting the plurality of support members 20 to converge radially inward or expand radially outward relative to the axis of the support frame 23. In this embodiment, compared to the previous embodiment, the operator can selectively control at least one of the first arm 200 and the second arm 210 to move axially relative to the catheter body 10 along the axial inner cavity, thereby adjusting the plurality of support members 20 to converge radially inward or expand radially outward relative to the axis of the support frame 23.

[0049] The first arm 200 and the second arm 210 can move within the same axial cavity of the catheter body 10, or they can move within different axial cavities. When the first arm 200 and the second arm 210 move within the same axial cavity of the catheter body 10, they can be spaced apart or not spaced apart. When the first arm 200 and the second arm 210 are spaced apart within the same axial cavity, two spaced guide tubes can be provided within that axial cavity, with the first arm 200 and the second arm respectively located within the two spaced guide tubes. When the first arm 200 and the second arm 210 are not spaced apart within the same axial cavity, the two guide tubes are not required.

[0050] See also Figure 3 and Figure 4In some embodiments, the first arm 200 and the second arm 210 can move within two spaced axial cavities of the catheter body 10. Specifically, the catheter body 10 has a first axial cavity 100 and a second axial cavity 110, which extend axially through the catheter body 10. The first arm 200 moves through the first axial cavity 100, and the second arm 210 moves through the second axial cavity 110. The first arm 200 and the second arm 210 can respectively pass through the first axial cavity 100 and the second axial cavity 110 and extend from the proximal end of the catheter body 10, facilitating operator control of the first arm 200 and / or the second arm 210 of the support member 20 to adjust the position of the support member 20.

[0051] As the multiple first arms 200 or multiple second arms 210 move proximally along the first axial inner cavity 100, the multiple support members 20 radially converge inward relative to the axis of the support frame 23, and the support frame 23 switches to a contracted state, with its radial dimension decreasing. Conversely, as the multiple first arms 200 or multiple second arms 210 move distally along the first axial inner cavity 100, the multiple support members 20 radially expand outward relative to the axis of the support frame 23, and the support frame 23 switches to an expanded state, with its radial dimension increasing. It is understood that, since both the first arms 200 and the second arms 210 can move axially, both the first arms 200 and the second arms 210 can also move proximally or distally, allowing the support frame 23 to switch between a contracted state and an expanded state.

[0052] In some embodiments, a plurality of support members 20 are arranged circumferentially around the axis of the support frame 23, and each support member 20 has adjacent support members 20 on its left and right sides. Figure 1 As shown, the first arm 200 of a support member 20 is cross-connected to the first arm 200 of the adjacent left support member 20, and the second arm 210 of the support member 20 is cross-connected to the second arm 210 of the adjacent right support member. The cross-connection serves to prevent misalignment of the positions of the two adjacent support members 20, allowing the support frame 23 in its expanded state to maintain its shape.

[0053] The cross-connection method can include various methods. In one feasible implementation, the first arm 200 or the second arm 210 of two adjacent support members 20 can be fixedly connected by welding or integral molding. During the process of the support member 20 moving towards the proximal or distal end relative to the conduit body 10, the fixed connection can make the connection between the two support members 20 more stable, avoid the position of the two adjacent support members 20 from shifting, and enable the support frame 23 to maintain its overall structural shape more stably.

[0054] In another feasible embodiment, please refer to Figure 1 In one of two adjacent support members 20, the first arm 200 of one support member 20 has a movable hole 24, and the first arm 200 of the other support member 20 is cross-connected to it through the movable hole 24. Alternatively, in another of the two adjacent support members 20, the second arm 210 of one support member 20 has a movable hole 24, and the second arm 200 of the other support member 20 is cross-connected to it through the movable hole 24. Connecting adjacent support members 20 through the movable hole 24 serves two purposes: firstly, it prevents the two support members 20 from separating and shifting; secondly, the movable hole allows for fine-tuning of the relative position of the two support members 20, making it convenient to use.

[0055] In another feasible embodiment, please continue to refer to Figure 1 A channel 230 can be provided on the bearing arm 220 of any of the two adjacent support members 20, which radially penetrates the bearing arm 220 and extends along the axial direction of the bearing arm 220. Another support member 20 passes through the channel 230. The two adjacent support members 20 are slidably connected through the channel 230. The two support members 20 can move relative to each other through the channel 230, so that the relative position of the two support members 20 can be adjusted within a large range without being separated.

[0056] Please continue reading Figures 1 to 5 In one embodiment, there are four support members 20 arranged circumferentially around the axis of the support frame 23. The ablation element 21 is an ablation electrode, and the ablation electrode is a ring electrode, which is sleeved on the support arm 220. An ablation electrode is provided at the midpoint of each support arm 220. The support frame 23 can switch between a contracted state and an expanded state. When the support frame 23 is switched to the contracted state, the structure formed by the four support arms 220 approaching the distal end face of the catheter body 10 presents a grid shape. The ablation electrodes on the four support arms 220 form an ablation ring with a smaller diameter (smaller than the outer diameter of the catheter body 10), thereby enabling local ablation of the lesion tissue. When the support frame 23 is switched to the expanded state, the multiple support members 20 open radially outward relative to the axis of the support frame 23. At this time, the ablation electrode on each support arm 220 forms a ring around the axis of the support frame, thereby enabling ring ablation of the pulmonary vein orifice.

[0057] It is understood that the number of support members 20 can be any suitable number, and the number of ablation electrodes on the same support arm 220 can also be two, three, or more, depending on the needs and the specific length of the support arm 220. It is also understood that in other embodiments, the ablation electrodes can be disposed on the first arm 200 or the second arm 210, or both the first arm 200 and the second arm 210 can be provided with ablation electrodes. The ablation electrodes can be arranged in an alternating circumferential positive and negative polarity configuration, or all electrodes can be positive with the negative electrode located outside the body. Furthermore, the ablation electrodes in this embodiment can also employ radiofrequency ablation energy.

[0058] In this embodiment, by controlling the first arm 200 and / or the second arm 210, the multiple supports 20 can switch between an expanded state and a contracted state, so that the ablation catheter 1 can perform both focal ablation and annular ablation, eliminating the need to prepare multiple ablation catheters for focal ablation and annular ablation respectively, which greatly saves costs.

[0059] Example 2, see Figures 6 to 7 The structure shown.

[0060] Figure 6 This is a schematic diagram of the ablation catheter when the supporting skeleton of the second embodiment of the present invention is in a contracted state. Figure 7 This is a schematic diagram of the ablation catheter when the supporting skeleton is in an expanded state according to the second embodiment of the present invention.

[0061] See also Figures 6 to 7 and combined Figures 1 to 5 The ablation catheter of this embodiment has the same basic structure as the ablation catheter of the first embodiment. The main difference lies in the structure of the supporting skeleton 23 and the method of contraction and expansion.

[0062] In this embodiment, the proximal ends of multiple support members 20 are rotatably connected to the distal ends of the catheter body 10. The support frame 23 also includes a drive member 30, which is movably inserted into the catheter body 10. The drive member 30 can move relative to the catheter body 10 along the axial direction of the catheter body 10 to drive the multiple support members 20 to converge radially inward or expand radially outward relative to the axis of the support frame 23. The drive member 30 can be configured as an inner liner tube, the inner lumen of which allows a guide wire to be inserted, so that an intervention channel can be established through the guide wire when the ablation catheter 1 is inserted into the blood vessel.

[0063] The shape of the support member 20 is not limited and can be sheet-like, rod-like or block-like. In this embodiment, the support member 20 is preferably sheet-like, as the sheet-like support member 20 has a larger surface area, which facilitates the installation of the ablation member 21.

[0064] In one embodiment, the support frame 23 further includes multiple linkages 31, each linkage 31 being connected to a support 20 in a one-to-one correspondence. One end of each linkage 31 is rotatably connected to a drive 30, and the other end is rotatably connected to the corresponding support 20. During the movement of the drive 30 relative to the catheter body 10 along its axial direction, the drive 30 can, through the multiple linkages 31, drive the multiple support 20 to radially converge inward or radially expand outward relative to the axis of the support frame 23. This allows for flexible adjustment of the radial dimensions of the support frame 23, enabling it to switch to the desired ablation ring or dot shape. Consequently, the ablation catheter 1 can achieve ring, dot, or linear ablation according to actual needs, rapidly and accurately ablating the lesion tissue with better ablation results.

[0065] See also Figure 7 In one embodiment, the two ends of the linkage 31 are spaced apart axially from the drive member 30. The linkage 31 extends obliquely from one end to the other. Multiple linkages 31 extend obliquely towards the circumferential side of the drive member 30 and towards the proximal end of the support frame 23. Understandably, the distal end of the linkage 31 is closer to the axis of the drive member 30 than the proximal end of the linkage 31. During the movement of the drive member 30 axially relative to the catheter body 10 towards the distal end, the drive member 30 can, through multiple linkages 31, cause multiple support members 20 to converge radially inward relative to the axis of the support frame 23, thus reducing the radial dimension of the support frame 23. During the movement of the drive member 30 axially relative to the catheter body 10 towards the proximal end, the drive member 30 can, through multiple linkages 31, cause multiple support members 20 to expand radially outward relative to the axis of the support frame 23, thus increasing the radial dimension of the support frame 23.

[0066] In another embodiment, the two ends of the linkage 31 are spaced apart axially from the drive member 30. The linkage 31 extends obliquely from one end to the other. Multiple linkages 31 extend obliquely towards the circumferential side of the drive member 30 and towards the distal end of the support frame 23. Understandably, the proximal end of the linkage 31 is closer to the axis of the drive member 30 than its distal end. During the movement of the drive member 30 proximally relative to the catheter body 10 along its axial direction, the drive member 30 can, through the multiple linkages 31, cause the distal ends of multiple supports 20 to converge radially inward relative to the axis of the support frame 23. During the movement of the drive member 30 distally relative to the catheter body 10 along its axial direction, the drive member 30 can, through the multiple linkages 31, cause the distal ends of multiple supports 20 to expand radially outward relative to the axis of the support frame 23.

[0067] In addition to rotatably connecting the support member 20 and the driving member 30 at both ends, the ends of the linkage member 31 can also be slidably connected to either the driving member 30 or the support member 20. In one embodiment, one end of the linkage member 31 is rotatably and slidably connected to the support member 20, while the other end is rotatably connected only to the driving member 30. In another embodiment, one end of the linkage member 31 is rotatably and slidably connected to the driving member 30, while the other end is rotatably connected only to the support member 20. In yet another embodiment, one end of the linkage member 31 is rotatably and slidably connected to the driving member 30, while the other end is rotatably and slidably connected to the support member 20. Compared to the method where the two ends of the linkage member 31 are only rotatably connected, the above three embodiments allow for a smoother process in which the driving member 30 drives the support member 20 to separate or converge via the linkage member 31.

[0068] The aforementioned multiple support members 20 may have ablation elements 21 installed on a portion of the support members 20, or all support members 20 may have ablation elements 21 installed on them. The number of ablation elements 21 installed on each support member 20 is not limited; it may be one or more.

[0069] like Figure 7 As shown, in one embodiment, each support member 20 is provided with an ablation element 21, which is an ablation electrode. The position of the ablation electrode on the support member 20 is not limited; it can be positioned near the proximal end or the distal end of the support member 20. In this embodiment, the ablation electrode is positioned near the distal end of the support member 20. When the multiple supports 20 are in the open state, the ablation electrodes on each support member 20 form an ablation ring with a larger diameter (greater than the outer diameter of the catheter body 10), thereby enabling circumferential ablation of the pulmonary vein orifice. When the multiple supports 20 are in the contracted state, the ablation electrodes on each support member 20 form an ablation circle with a smaller diameter (equal to the outer diameter of the catheter body 10), thereby enabling local ablation of the lesion tissue.

[0070] Since multiple support members 20 are arranged circumferentially around the axial direction of the catheter body 10, multiple ablation electrodes are also arranged circumferentially around the axial direction of the catheter body 10. The relative positions of the multiple ablation electrodes are not limited; they may not be located in the same plane or may be located in the same plane. In this embodiment, the plane in which the multiple ablation electrodes are located is a plane perpendicular to the axial direction of the catheter body 10. That is, the multiple ablation electrodes form a ring around the axis of the catheter body 10 in the circumferential direction, so that the multiple ablation electrodes can uniformly ablate the target tissue area, which is convenient for operation.

[0071] In an optional embodiment, the support member 20 can also automatically rotate and radially expand relative to the catheter body 10. Specifically, the proximal end of the support member 20 and the distal end of the catheter body 10 can be connected by an elastic body, such as a torsion spring, elastic gel, or spring sheet. The support member 20 is rotatably connected to the catheter body 10 via the torsion spring, so that the multiple support members 20 tend to converge radially inward relative to the support frame 23 in their natural state, that is, in their natural state, the multiple support members 20 converge towards each other. When the operator applies a force to the multiple support members 20 through the drive member 30, the multiple support members 20 radially expand outward relative to the axis of the support frame 23. Alternatively, the multiple support members 20 can be configured to tend to expand radially outward relative to the support frame 23 in their natural state, and only converge radially inward relative to the axis of the support frame 23 when the operator applies a force to the multiple support members 20 through the drive member 30. With the above configuration, it is more convenient for the operator to control the ablation catheter 1.

[0072] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0073] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications, substitutions, and improvements without departing from the concept of the present invention, and these should all be covered within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the claims.

Claims

1. An ablation catheter, characterized in that, include: Catheter body; An ablation assembly is disposed at the distal end of the catheter body. The ablation assembly includes a support frame and at least one ablation element disposed on the support frame. The support frame includes a plurality of support elements, which are arranged circumferentially around the axis of the support frame. The proximal and distal ends of the support elements are spaced apart in the radial direction of the support frame. The support member includes two support arms and a load-bearing arm. The two ends of the load-bearing arm are respectively connected to the distal ends of the two support arms. The two support arms are movably inserted into the catheter body and can move proximally or distally along the catheter body, so that the multiple support members can converge radially inward or expand radially outward relative to the axis of the support frame. A channel is formed in the bearing arm of any one of two adjacent support members, extending radially through the bearing arm and along the axial direction of the bearing arm. The other support member passes through the channel, so that the two adjacent support members are slidably connected through the channel. The support frame is capable of switching between a contracted state and an expanded state. When the support frame switches to the contracted state, multiple support members converge radially inward relative to the axis of the support frame. The bearing arm and the ablation element disposed on the bearing arm are located at the distal end of the catheter body for local ablation. When the support frame switches to the expanded state, multiple support members expand radially outward relative to the axis of the support frame.

2. The ablation catheter according to claim 1, characterized in that, The catheter body has an axial inner cavity, and the support member is movably inserted into the axial inner cavity; As the plurality of support members move proximally along the axial inner cavity, the plurality of support members converge radially inward relative to the axis of the support frame. As the plurality of support members move toward the distal end along the axial inner cavity, the plurality of support members open radially outward relative to the axis of the support frame.

3. The ablation catheter according to claim 2, characterized in that, The two support arms are movably inserted into the axial cavity, and the two support arms can move proximally or distally along the axial cavity.

4. The ablation catheter according to claim 3, characterized in that, The two support arms are spaced apart, and the two support arms, the bearing arm, and the distal end face of the catheter body form a hollow hole.

5. The ablation catheter according to claim 4, characterized in that, The axial inner cavity includes a first axial inner cavity and a second axial inner cavity. One of the two support arms is movably inserted through the first axial inner cavity, and the other support arm is movably inserted through the second axial inner cavity. One of the two arms is movable proximally along the first axial cavity, and / or the other arm is movable proximally along the second axial cavity; or One of the two arms is movable distally along the first axial cavity, and / or the other arm is movable distally along the second axial cavity.

6. The ablation catheter according to any one of claims 3-5, characterized in that, At least one of the ablation elements is disposed on the support arm, and the ablation element is an electrode.

7. The ablation catheter according to claim 6, characterized in that, At least one electrode is provided on each of the support arms; When the support frame is in the expanded state, at least one electrode on each of the bearing arms forms a ring around the axis of the support frame in the circumferential direction.

8. The ablation catheter according to claim 7, characterized in that, The electrode includes a positive electrode and a negative electrode, which are alternately arranged in the circumferential direction around the axis of the support frame.

9. The ablation catheter according to claim 1, characterized in that, The ablation catheter also includes a traction element, the distal end of which is connected to the proximal end of a plurality of the support elements. The traction element can drive the plurality of support elements to move relative to the catheter body, so that the support frame switches between the contracted state and the expanded state.

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