Radio frequency ablation catheter and radio frequency ablation equipment

Abstract

The embodiment of the invention provides a radiofrequency ablation catheter and radiofrequency ablation equipment. The radiofrequency ablation catheter comprises an electrode support capable of contracting and expanding in the radial direction, a connecting tube and a center wire. The near end of the connecting tube is connected with the far end of the electrode support, and the connecting tube is provided with a first cavity channel penetrating through the near end and the far end; the central wire is movably arranged in the electrode bracket and the first cavity in a penetrating manner; a first limiting part is arranged on the center wire, the first limiting part is located in the first cavity channel, and a second limiting part is correspondingly arranged on the inner wall of the first cavity channel; when the first limiting part abuts against the second limiting part and the center wire moves from the far end to the near end, the electrode support is switched from the contraction state to the expansion state. According to the technical scheme, the risk of damaging the blood vessel can be reduced, the precision of selecting the target branch blood vessel by the central wire is improved, and then the ablation efficiency of radiofrequency ablation is improved.

Description

Technical Field

[0001] The present application relates to the technical field of radiofrequency ablation, and in particular to a radiofrequency ablation catheter and a radiofrequency ablation device. Background Art

[0002] At present, radiofrequency ablation technology is widely used in the medical field. Radiofrequency ablation catheters carrying multiple electrodes can greatly improve radiofrequency efficiency. Radiofrequency ablation surgery to ablate overactive renal artery sympathetic nerves is a typical method for treating refractory hypertension. This surgery can use a catheter with radiofrequency electrodes to reach the ablation target location through the radial artery or femoral artery to ablate the sympathetic nerves, thereby achieving the effect of treating hypertension.

[0003] Before the operation begins, the radiofrequency ablation catheter needs to enter the blood vessel with the help of the central wire, and the ablation catheter is introduced into the target branch blood vessel for ablation using the central wire. After the ablation catheter moves to the ablation position, the central wire is withdrawn, and then radiofrequency ablation is performed. When multiple target ablation areas need to be ablated during the same operation, the central wire needs to be inserted and extracted multiple times, which is cumbersome and inconvenient, and easily increases the risk during the operation.

[0004] Of course, there are also technical solutions in the prior art that combine the center wire with radiofrequency ablation. The distal end of the center wire is provided with a limiting structure, and the center wire can move axially relative to the catheter and will not separate from the catheter under the action of the limiting structure. The distal end of the center wire extends out of the distal end of the catheter, and can enter the target branch blood vessel to play the function of branch superselection. When the limiting structure of the center wire abuts against the end of the electrode stent, the center wire continues to be withdrawn, and the expansion function of the electrode stent can be realized. However, in actual use, there are still problems such as low branch superselection accuracy and easy damage to blood vessels. Summary of the invention

[0005] The present application provides a radiofrequency ablation catheter and a radiofrequency ablation device, which can reduce the risk of damaging blood vessels, improve the accuracy of central wire selection of target branch blood vessels, and thus improve the ablation efficiency of radiofrequency ablation.

[0006] This application is achieved through the following technical solutions:

[0007] In a first aspect, an embodiment of the present application provides a radiofrequency ablation catheter, which includes an electrode holder that can radially contract and expand, a connecting tube and a center wire; the proximal end of the connecting tube is connected to the distal end of the electrode holder, and the connecting tube has a first lumen that runs through its proximal and distal ends; the center wire is movably arranged in the electrode holder and the first lumen; wherein a first limiting portion is provided on the center wire, the first limiting portion is located in the first lumen, and a second limiting portion is correspondingly provided on the inner wall of the first lumen; when the first limiting portion abuts against the second limiting portion, and the center wire moves from the distal end to the proximal end, the electrode holder switches from a contracted state to an expanded state.

[0008] In this solution, the center wire can be movably arranged in the electrode support and the first lumen, and the distal end of the center wire extends out of the connecting tube to guide the radiofrequency ablation catheter to enter the target branch blood vessel, so as to realize the function of branch superselection. A first limiting portion is arranged on the center wire, and a second limiting portion is correspondingly arranged on the inner wall of the first lumen. After the first limiting portion and the second limiting portion are blocked and matched, the center wire can be continuously withdrawn to realize the expansion function of the electrode support, so that the electrode on the electrode support is attached to the wall for radiofrequency ablation. By both the first limiting portion and the second limiting portion being built into the first lumen, compared with the method of setting a blocking structure at the distal end of the center wire and abutting the end face between the electrodes, when the distal end of the center wire is used for branch superselection, since the first limiting portion is built into the first lumen, the first limiting portion of the center wire will not be exposed outside the connecting tube, so that the size of the distal end of the center wire is relatively smaller, and the distal end of the center wire is not easy to scratch the blood vessel when selecting the target branch blood vessel, thereby reducing the risk of damaging the blood vessel. Furthermore, since the distal end of the center wire is smaller in size, it is less likely for the center wire to collide with or get stuck on the wall of the branch vessel and the center wire can be easily rotated or pulled back and forth. The movement or rotation of the center wire is smoother and the center wire is more controllable. The center wire can enter the target branch vessel more easily, reducing the difficulty of the center wire selecting the target branch vessel and improving the accuracy of the center wire branch superselection, thereby improving the efficiency of radiofrequency ablation.

[0009] According to some embodiments of the present application, a third limiting portion is provided on the central wire, and the third limiting portion and the first limiting portion are respectively located on opposite sides of the second limiting portion; when the third limiting portion abuts against the second limiting portion and the central wire moves from the proximal end to the distal end, the electrode bracket can switch from an expanded state to a contracted state.

[0010] In the above scheme, by providing a third limiting portion on the central wire, the third limiting portion can be abutted and matched with the second limiting portion. When the central wire moves from the proximal end to the distal end, on the one hand, it can play an auxiliary role for the electrode bracket, apply a contraction force toward the distal end to the electrode bracket, and switch the electrode bracket to a contracted state, so that the radial size of the electrode bracket after contraction is smaller, which is conducive to the movement of the electrode bracket in the blood vessel, and avoid the phenomenon that the contraction effect of the electrode bracket is not good due to the limited reset ability of the electrode bracket itself, thereby increasing the radial size of the electrode bracket, and the radiofrequency ablation catheter moves poorly in the blood vessel or even scratches the blood vessel. On the other hand, the third limiting portion abuts and cooperates with the second limiting portion, which can play a role in limiting the extension length of the distal end of the central wire, and avoid the phenomenon that the central wire and the connecting tube are separated.

[0011] According to some embodiments of the present application, the central wire includes a guidewire body and a soft guidewire disposed at the distal end of the guidewire body, and the first limiting portion is disposed on the guidewire body.

[0012] In the above scheme, the center wire includes a guide wire body and a soft guide wire. When the center wire selects the target branch blood vessel through the soft guide wire at its distal end, on the one hand, after the soft guide wire contacts the blood vessel wall, it will adaptively deform following the curvature of the blood vessel wall, so that the soft guide wire has a guiding function, which is beneficial for the center wire to enter the corresponding branch blood vessel through the soft guide wire, thereby improving the efficiency of branch superselection. On the other hand, the soft guide wire is made of a flexible material. After the soft guide wire contacts the blood vessel wall, the soft guide wire deforms, avoiding rigid contact between the center wire and the blood vessel, thereby reducing the probability of damage to the blood vessel.

[0013] According to some embodiments of the present application, along the radial direction of the soft guide wire, the soft guide wire includes an inner layer, an intermediate layer and an outer layer from the inside to the outside, the inner layer is made of nickel-titanium grinding alloy wire, the intermediate layer is a high-density metal alloy spring, and the outer layer is a stainless steel spring. In the above scheme, since the nickel-titanium grinding alloy wire is a superelastic shape memory alloy, it cannot be directly shaped. The springs of the intermediate layer and the outer layer are plastically deformable, and the shape of the extremely fine grinding wire of the inner layer can be changed by adjusting the shaping shape of the springs of the intermediate layer and the outer layer, thereby achieving the clinical shaping shape requirements of the surgeon. The soft guide wire has its own angle, and when the doctor wants to enter different blood vessel branches, there will be a need to adjust the angle of the front end of the center wire, which can achieve the angle change of the center wire to meet the requirements of entering different blood vessel branches and improve the efficiency of branch superselection.

[0014] According to some embodiments of the present application, the connecting tube includes a polymer material layer and an elastic structure layer, the elastic structure layer is embedded inside the polymer material layer, and the elastic structure layer encloses and defines a first cavity.

[0015] In the above scheme, the polymer material layer constitutes the main material of the connecting tube, so that the connecting tube has a certain strength and bending deformation ability, and can adapt to the tortuous path of the blood vessel. An elastic structural layer is arranged in the connecting tube, and the elastic structural layer encloses and forms the first cavity. When the connecting tube is bent and deformed due to adapting to the blood vessel, under the support of the elastic structural layer, the first cavity is not easily flattened or squeezed and deformed, thereby ensuring that the central wire has sufficient activity space in the first cavity, and the central wire can move smoothly (rotate or move axially) in the first cavity, and it is not easy to affect the branch superselection function of the central wire.

[0016] According to some embodiments of the present application, the elastic structural layer is a metal woven mesh layer.

[0017] In the above scheme, the elastic structural layer is made of a metal woven layer mesh, which encloses the first cavity to form a first cavity. The metal woven layer can provide support performance for the first cavity. When the connecting tube is bent and deformed due to adapting to the blood vessel, the first cavity is not easily flattened or squeezed and deformed under the support of the metal woven layer mesh, thereby ensuring that the central wire has sufficient space for movement in the first cavity, which is conducive to the smooth movement of the central wire in the first cavity and is not easy to affect the branch superselection function of the central wire.

[0018] According to some embodiments of the present application, the elastic structural layer is a spring.

[0019] In the above scheme, by using the elastic structural layer as a spring, due to the characteristics of the spring itself, the spring provides a certain elasticity and support performance to the connecting tube, so that the connecting tube not only has a certain toughness, but also has better bending performance. After the connecting tube enters the branch of the blood vessel, on the one hand, the spring can further enhance the bending performance and deformation recovery performance of the connecting tube, so that the connecting tube can more easily adapt to the bending of the branch blood vessel and adaptively bend and deform, reducing the probability of the connecting tube damaging the blood vessel. When the connecting tube loses the compression effect of the blood vessel wall, the connecting tube can be more easily and quickly reset under the reset effect of the spring, enhancing the bending performance and reset ability of the connecting tube. On the other hand, the spring encloses to form the first cavity. When the connecting tube bends and deforms due to adapting to the blood vessel, under the support of the spring, the first cavity is not easy to be flattened or squeezed, thereby ensuring that the center wire has sufficient activity space in the first cavity, which is conducive to the smooth movement of the center wire in the first cavity and is not easy to affect the branch superselection function of the center wire.

[0020] According to some embodiments of the present application, a lubricating layer is provided on the inner side of the elastic structural layer, and the lubricating layer is used to reduce the friction force when the central wire and the elastic structural layer slide relative to each other.

[0021] In the above scheme, a lubricating layer is provided on the inner side of the elastic structural layer, and the lubricating layer is in contact with the center wire. Compared with the contact between the center wire and the elastic structural layer, the lubricating layer can reduce the friction force when the center wire and the elastic structural layer slide relative to each other, so that the movement of the center wire in the first cavity is smoother, the adjustment of the center wire is smoother, and it is not easy to interfere with or hinder the elastic structural layer.

[0022] According to some embodiments of the present application, the lubricating layer is a polytetrafluoroethylene etched tube.

[0023] In the above scheme, by using a polytetrafluoroethylene etched tube as the lubricating layer, and compared with applying a lubricating coating on the inner wall of the first cavity, the polytetrafluoroethylene etched tube has better durability, so that the outer wall of the center wire contacts the inner wall of the polytetrafluoroethylene etched tube, the inner wall of the polytetrafluoroethylene etched tube is relatively smooth, the center wire can move more smoothly in the first cavity, and the center wire can more flexibly select the target branch blood vessel.

[0024] According to some embodiments of the present application, a connector is provided at the distal end of the electrode bracket, the connector is embedded in the proximal end of the connecting tube, and the connector is hot-melt connected to the polymer material layer of the connecting tube.

[0025] In the above scheme, a connector is provided at the distal end of the electrode holder, which acts as an intermediate transition, so that the mesh tube of the electrode holder can be pre-connected with the connector as a whole, and then hot-melt connected with the polymer material layer of the connecting tube, thereby reducing the difficulty of connecting the electrode holder and the connecting tube.

[0026] According to some embodiments of the present application, the connecting member is an annular metal sheet.

[0027] In the above scheme, the metal sheet is used as the connector, which is easy to be welded and fixed to the mesh tube of the electrode support, and the connection stability is good. The connector is an annular structure, which is convenient for the subsequent connector and the elastic structure layer to have sufficient welding area in the circumferential direction, and it is easy to ensure the connection strength between the elastic structure layer and the connector.

[0028] According to some embodiments of the present application, the elastic structural layer is welded to the connecting piece.

[0029] In the above scheme, during the assembly of the connecting pipe, the elastic structure layer can be welded to the connecting piece first to achieve pre-connection of the elastic structure layer and the connecting piece. When the polymer material layer of the connecting pipe is subsequently hot-melted, the position of the elastic structure layer is not easily changed, which is convenient for the molding accuracy of the connecting pipe. After the elastic structure layer and the connecting piece are welded, the installation stability of the elastic structure layer in the connecting pipe can be further enhanced.

[0030] According to some embodiments of the present application, from the proximal end to the distal end, the inner diameter of the first cavity is the same, and the outer diameter of the connecting tube gradually decreases.

[0031] In the above scheme, the outer diameter of the connecting tube is gradually reduced from the proximal end to the distal end, and the connecting tube is tapered. The distal end of the connecting tube serves as a guide, which is more conducive to the connecting tube entering the target branch blood vessel.

[0032] According to some embodiments of the present application, the radiofrequency ablation catheter also includes a catheter, which is connected to one end of the electrode holder away from the connecting tube, and has a second lumen extending along its axial direction, and the central wire is sequentially arranged in the second lumen, the electrode holder and the first lumen.

[0033] In the above scheme, the catheter can provide the function of accommodating various wires or central wires of the radiofrequency ablation catheter. The second lumen of the catheter can be used for the central wire to pass through. After the central wire passes through the second lumen, the electrode bracket and the first lumen in sequence, the central wire extends out of the connecting tube to provide the function of branch superselection.

[0034] According to some embodiments of the present application, the radiofrequency ablation catheter further includes an operating handle, which is disposed on the proximal side of the catheter and connected to the proximal end of the center wire for controlling the movement of the center wire relative to the catheter.

[0035] In the above scheme, through the setting of the operating handle, the operating handle is connected to the proximal end of the center wire, and the operating handle plays the role of controlling the movement of the center wire. It can drive the center wire to move or rotate axially relative to the catheter according to needs, thereby realizing the distal rotation of the center wire to explore the target branch blood vessel and realize the function of branch super selection.

[0036] In a second aspect, an embodiment of the present application further provides a radiofrequency ablation device, the radiofrequency ablation device comprising the radiofrequency ablation catheter of any of the aforementioned embodiments.

[0037] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0039] Figure 1 A schematic diagram of the structure of an electrode stent in an expanded state in a radiofrequency ablation catheter provided in some embodiments of the present application;

[0040] Figure 2 A schematic diagram of the structure of an electrode support in a radiofrequency ablation catheter in some embodiments of the present application in a contracted state;

[0041] Figure 3 for Figure 1 Sectional view of AA in the middle;

[0042] Figure 4 for Figure 3 A is an enlarged schematic diagram;

[0043] Figure 5 A schematic diagram of the structure of a radiofrequency ablation catheter provided in some embodiments of the present application;

[0044] Figure 6 for Figure 5 A magnified schematic diagram of B;

[0045] Figure 7 A schematic diagram of the structure of the operation handle and the central wire in the radiofrequency ablation catheter provided in some embodiments of the present application;

[0046] Figure 8 for Figure 7 Sectional view of AA in the middle;

[0047] Fig. 9 for Figure 8 An enlarged schematic diagram of the operating handle.

[0048] Icons: 100-radiofrequency ablation catheter; 10-catheter; 11-second cavity; 20-electrode holder; 21-connecting piece; 22-electrode; 30-connecting tube; 31-polymer material layer; 32-elastic structure layer; 33-lubricating layer; 34-first cavity; 35-second limiting part; 40-center wire; 41-first limiting part; 42-third limiting part; 43-guidewire body; 44-soft guidewire; 441-inner layer; 442-middle layer; 443-outer layer; 50-operating handle; 51-handle; 511-installing cavity; 52-operating piece; 521-main body; 522-rotating handle; 523-fixing piece. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0050] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0051] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0052] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0053] There are also technical solutions combining the center wire with radiofrequency ablation in the prior art, such as the patent with publication number CN111513837B. In this solution, a limiting structure is set at the distal end of the center wire, and the center wire can move axially relative to the catheter and will not separate from the catheter under the action of the limiting structure. The distal end of the center wire extends out of the distal end of the catheter, and can enter the target branch blood vessel to play the function of branch superselection. When the limiting structure of the center wire abuts against the end of the electrode stent, the center wire continues to be withdrawn, and the expansion function of the electrode stent can be realized. However, in actual use, there are still problems such as low branch superselection accuracy and easy damage to blood vessels.

[0054] Specifically, a blocking structure is provided at the distal end of the central wire, and the blocking structure at the distal end of the central wire abuts and cooperates with the end face of the distal end of the electrode holder, and the expansion function of the electrode holder can also be realized. Although the function of selecting branch superselection can be achieved by probing into the target branch blood vessel through the distal end of the central wire, when the distal end of the central wire is used for branch superselection, due to the narrow and tortuous space of the branch blood vessel, the blocking structure at the distal end of the central wire increases the size of the distal end of the central wire, and the blocking structure of the central wire is prone to abutment or blocking with the blood vessel wall, which not only affects the forward and backward movement of the central wire, but also when the central wire is rotated to select the corresponding branch blood vessel, the blocking structure is prone to contact with the blood vessel wall, affecting the rotation or rotation accuracy of the central wire, making the controllability of the central wire lower, affecting the accuracy of branch superselection, and even causing damage to the blood vessel.

[0055] For example, when the proximal end of the center wire rotates 50° along the preset direction, the blocking structure at the distal end of the center wire may abut against the blood vessel wall, so the rotation amplitude of the distal end of the center wire may be less than 50°, that is, the distal end of the center wire is twisted. Then, when the angle of the center wire is further rotated 50° along the preset direction, the distal end of the center wire suddenly overcomes the twisted state under the action of the rotation force, so that the distal end of the center wire is restored, and the rotation angle of the distal end of the center wire is greater than 50°. In this process, the center wire will suddenly swing too much, making the center wire or the blocking structure at the distal end of the center wire prone to damage the blood vessel. That is, in terms of the method of setting the blocking structure at the distal end of the center wire, the center wire is prone to uncontrollable swing amplitude during the adjustment process, the precision of the branch superselection of the center wire is low, and it is easy to cause damage to the blood vessel.

[0056] In view of this, the present application embodiment provides a radiofrequency ablation catheter, please refer to Figures 1 to 4 The radiofrequency ablation catheter 100 includes an electrode holder 20, a connecting tube 30 and a center wire 40 which can be radially contracted and expanded; the proximal end of the connecting tube 30 is connected to the distal end of the electrode holder 20, and the connecting tube 30 has a first lumen 34 which runs through its proximal and distal ends; the center wire 40 is movably arranged in the electrode holder 20 and the first lumen 34; wherein a first limiting portion 41 is arranged on the center wire 40, the first limiting portion 41 is located in the first lumen 34, and a second limiting portion 35 is correspondingly arranged on the inner wall of the first lumen 34; when the first limiting portion 41 abuts against the second limiting portion 35, and the center wire 40 moves from the distal end to the proximal end, the electrode holder 20 switches from a contracted state to an expanded state, Figure 1 The schematic diagram of the structure of the electrode stent in the expanded state is shown in FIG. Figure 2 FIG. 2 shows a schematic diagram of the structure of the electrode holder in a contracted state.

[0057] In this solution, the center wire 40 can be movably arranged in the electrode holder 20 and the first lumen 34, and the distal end of the center wire 40 extends out of the connecting tube 30 to guide the radiofrequency ablation catheter 100 to enter the target branch blood vessel, so as to realize the function of branch superselection. A first limiting portion 41 is arranged on the center wire 40, and a second limiting portion 35 is correspondingly arranged on the inner wall of the first lumen 34. After the first limiting portion 41 and the second limiting portion 35 are blocked and matched, the center wire 40 is continuously withdrawn to realize the expansion function of the electrode holder 20, so that the electrode 22 on the electrode holder 20 is attached to the wall for radiofrequency ablation. By embedding both the first limiting portion 41 and the second limiting portion 35 in the first lumen 34, compared with the method of setting a blocking structure at the distal end of the central wire 40 and abutting the end surface between the electrode 22, when using the distal end of the central wire 40 for branch superselection, since the first limiting portion 41 is embedded in the first lumen 34, the first limiting portion 41 of the central wire 40 will not be exposed outside the connecting tube 30, so that the size of the distal end of the central wire 40 is relatively smaller, and the distal end of the central wire 40 is not easy to scratch the blood vessel when selecting the target branch blood vessel, thereby reducing the risk of damaging the blood vessel. In addition, since the size of the distal end of the central wire 40 is smaller, the central wire 40 is not easy to conflict with or get stuck on the wall of the branch blood vessel, and the central wire 40 can be easily rotated or pulled forward and backward, and the movement or rotation of the central wire 40 is smoother, the controllability of the central wire 40 is stronger, and the central wire 40 can more easily enter the target branch blood vessel, reducing the difficulty of the central wire 40 selecting the target branch blood vessel, and improving the accuracy of the branch superselection of the central wire 40, thereby improving the efficiency of radiofrequency ablation.

[0058] The electrode bracket 20 may be in the shape of a mesh tube bracket, which is a mesh structure with a certain length, and is a mesh structure formed by a single wire or multiple wires being woven in a forward and reverse spiral. During the process of the electrode bracket 20 expanding and adhering to the wall, the braided wires interwoven around each node of the electrode bracket 20 provide support to each other, and the electrode bracket 20 is not prone to lodging.

[0059] The electrode holder 20 has a contracted state and an expanded state. One or more electrodes 22 are attached to the braided wire of the middle section of the electrode holder 20. The middle section of the electrode holder 20 can expand in all directions under the action of the central wire 40, so that the electrodes 22 on the electrode holder 20 adhere to the blood vessel wall. The electrode 22 can be a block electrode or a ring electrode. The outer surface of the electrode 22 is higher than the outer surface of the braided wire, so that the electrode 22 is fully in contact with the blood vessel wall, improving the wall adhesion effect.

[0060] The braided wire of the electrode holder 20 can be made of metal material or polymer material, such as stainless steel, nickel titanium or cobalt nickel. By pulling the center wire 40, after the first limiter 41 on the center wire 40 abuts against the second limiter 35 in the first lumen 34, the center wire 40 is continuously pulled toward the proximal direction, and the center wire 40 can drive the electrode holder 20 to move toward the proximal side to achieve the expansion of the electrode holder 20, so as to adjust the wall adhesion effect of the electrode 22 on the electrode holder 20, and the electrode holder 20 can be suitable for blood vessel lumens of different diameters.

[0061] The proximal end refers to the end close to the operator, and the distal end refers to the end far from the operator. Taking the proximal end and the distal end of the connecting tube 30 as an example, the proximal end of the connecting tube 30 refers to the end of the connecting tube 30 close to the operator, and the distal end of the connecting tube 30 refers to the end of the connecting tube 30 far from the operator. The proximal end and the distal end are respectively located at the two ends of the axial direction of the connecting tube 30.

[0062] The connecting tube 30 refers to an end structure disposed at the distal end of the electrode holder 20, and the proximal end of the connecting tube 30 is fixedly connected to the distal end of the electrode holder 20. The first lumen 34 refers to an internal lumen of the connecting tube 30, through which the central wire 40 is arranged. The first lumen 34 runs through the proximal end and the distal end of the connecting tube 30.

[0063] The distal end of the center wire 40 may be straight, curved or arc-shaped. Optionally, the distal end of the center wire 40 is curved, that is, the distal end of the center wire 40 has an elbow. The center wire 40 is movably arranged in the first lumen 34 of the electrode holder 20 and the connecting tube 30, which means that the center wire 40 can move or slide along the axial direction in the first lumen 34, and can also rotate around the central axis direction of the center wire 40 in the first lumen 34.

[0064] When using the distal end of the center wire 40 to select a target branch vessel, the center wire 40 can move axially to adjust the extension length of the distal end of the center wire 40 outside the connecting tube 30 to facilitate the selection and entry of the target branch vessel. The center wire 40 can also rotate around its central axis to allow the elbow at the distal end of the center wire 40 to rotate, so as to facilitate more flexible selection of the target branch vessel.

[0065] The first limiting portion 41 refers to a protruding structure protruding from the outer peripheral surface of the center wire 40. The material of the first limiting portion 41 can be metal or other materials. In this embodiment, the first limiting portion 41 is a metal sheet, and the first limiting portion 41 can be welded and fixed on the center wire 40.

[0066] The outer diameter of the first stopper 41 is smaller than the inner diameter of the first lumen 34, and the first stopper 41 can rotate in the first lumen 34 or move along the axial direction of the connecting tube 30 following the center wire 40. The second stopper 35 refers to a protruding structure protruding from the inner wall of the first lumen 34 in the first lumen 34 of the connecting tube 30.

[0067] According to some embodiments of the present application, a third limiting portion 42 is provided on the central wire 40, and the third limiting portion 42 and the first limiting portion 41 are respectively located on opposite sides of the second limiting portion 35; when the third limiting portion 42 abuts against the second limiting portion 35 and the central wire 40 moves from the proximal end to the distal end, the electrode bracket 20 can switch from the expanded state to the contracted state.

[0068] The third limiting portion 42 and the first limiting portion 41 are both located in the first cavity 34, and are respectively located on opposite sides of the second limiting portion 35. The structures of the third limiting portion 42 and the first limiting portion 41 can be the same or different. The third limiting portion 42 refers to a protruding structure protruding from the outer peripheral surface of the center wire 40, and the material of the third limiting portion 42 can be metal or other materials. In the present embodiment, the third limiting portion 42 is a metal sheet, and the third limiting portion 42 is welded on the center wire 40.

[0069] By providing the third limiting portion 42 on the center wire 40, the third limiting portion 42 can be abutted and matched with the second limiting portion 35. When the center wire 40 moves from the proximal end to the distal end, on the one hand, it can play an auxiliary role for the electrode holder 20, apply a contraction force toward the distal end to the electrode holder 20, and switch the electrode holder 20 to a contracted state, so that the radial dimension of the electrode holder 20 after contraction is smaller, which is conducive to the movement of the electrode holder 20 in the blood vessel, and avoid the limited reset ability of the electrode holder 20 itself, the poor contraction effect of the electrode holder 20, and thus increase the radial dimension of the electrode holder 20, resulting in the phenomenon that the radiofrequency ablation catheter 100 moves poorly in the blood vessel or even scratches the blood vessel. On the other hand, the third limiting portion 42 and the second limiting portion 35 abut and cooperate, which can play a role in limiting the extension length of the distal end of the center wire 40, and avoid the phenomenon that the center wire 40 and the connecting tube 30 are separated.

[0070] According to some embodiments of this application, please refer to Figure 1 The center wire 40 includes a guide wire body 43 and a soft guide wire 44 disposed at the distal end of the guide wire body 43 , and the first limiting portion 41 is disposed on the guide wire body 43 .

[0071] The guide wire body 43 is a metal wire, such as a nickel-titanium grinding alloy wire. During the movement of the center wire 40, the soft guide wire 44 is always located at or remains on one side outside the far end of the connecting tube 30.

[0072] The angle between the soft guide wire 44 and the guide wire body 43 is 45°. The shape of the distal end of the soft guide wire 44 can be a straight line, a curve, an arc, etc., including but not limited to an L-shape, a straight line or an arc, so that the target branch vessel can be selected more flexibly. Optionally, the distal end of the soft guide wire 44 is an arc.

[0073] The angle between the soft guide wire 44 and the guide wire body 43 can be 0° to 90°. That is, the angle between the soft guide wire 44 and the guide wire body 43 can be 10°, 20°, 30°, 40°, 45°, 50°, 55°, 60°, 70° or 80°.

[0074] The center wire 40 includes a guide wire body 43 and a soft guide wire 44. When the center wire 40 selects a target branch vessel through the soft guide wire 44 at its distal end, on the one hand, after the soft guide wire 44 contacts the vessel wall, it will deform adaptively following the curvature of the vessel wall, so that the soft guide wire 44 has a guiding function, which is beneficial for the center wire 40 to enter the corresponding branch vessel through the soft guide wire 44, thereby improving the efficiency of branch superselection. On the other hand, the soft guide wire 44 is made of a flexible material. After the soft guide wire 44 contacts the vessel wall, the soft guide wire 44 deforms, avoiding the center wire 40 from rigidly contacting the vessel, thereby reducing the probability of damage to the vessel.

[0075] According to some embodiments of this application, please combine Figure 5 and Figure 6 Along the radial direction of the soft guide wire 44, the soft guide wire 44 includes an inner layer 441, a middle layer 442 and an outer layer 443 from the inside to the outside. The inner layer 441 is made of nickel-titanium ground alloy wire, the middle layer 442 is a high-density metal alloy spring, and the outer layer 443 is a stainless steel spring.

[0076] The inner layer 441 is a shape memory alloy-nickel-titanium alloy, and the middle layer 442 can be a high-density metal alloy spring of a development-enhanced type, such as platinum-tungsten, platinum-nickel, etc. The outer layer 443 is a stainless steel spring-304, 316 stainless steel. Of course, the guide wire body 43 can be a single-layer structure, that is, the material of the guide wire body is nickel-titanium grinding alloy wire, which is the same as the material of the inner layer 441, and the inner layer 441 of the soft guide wire 44 is integrally formed with the guide wire body 43.

[0077] Since the nickel-titanium grinding alloy wire of the inner layer 441 is a superelastic shape memory alloy, it cannot be directly shaped. The springs of the middle layer 442 and the outer layer 443 are plastically deformable, and the shape of the extremely fine grinding wire of the inner layer 441 can be driven to change by adjusting the shaping shape of the springs of the middle layer 442 and the outer layer 443, thereby achieving the surgeon's clinical shaping shape requirements. The soft guide wire 44 has its own angle, and when the doctor wants to enter different blood vessel branches, he will need to adjust the angle of the front end of the center wire 40, which can achieve the angle change of the center wire 40 to meet the requirements of entering different blood vessel branches and improve the efficiency of branch superselection.

[0078] According to some embodiments of this application, please refer to Figure 4 The connecting tube 30 includes a polymer material layer 31 and an elastic structure layer 32 . The elastic structure layer 32 is embedded inside the polymer material layer 31 . The elastic structure layer 32 encloses and defines a first cavity 34 .

[0079] The polymer material layer 31 may be made of TPU or PEBAX. TPU (Thermoplastic Polyurethanes) is a type of elastomer that can be plasticized by heating and dissolved by solvents, and has excellent comprehensive properties such as high strength, high toughness, wear resistance, oil resistance, and good processing performance.

[0080] PEBAX (Poly Ether Block Amide) is composed of regular linear hard polyamide segments embedded with soft polyether segments.

[0081] The elastic structural layer 32 refers to a structural layer that can provide a certain rigidity to the first cavity 34 . The elastic structural layer 32 can be made of various materials. For example, the elastic structural layer 32 can be made of a spring or a metal braided layer.

[0082] The polymer material layer 31 constitutes the main material of the connecting tube 30, so that the connecting tube 30 has a certain strength and bending deformation ability, and can adapt to the tortuous path of the blood vessel. An elastic structure layer 32 is arranged in the connecting tube 30, and the elastic structure layer 32 encloses and forms the first cavity 34. When the connecting tube 30 is bent and deformed due to adapting to the blood vessel, under the support of the elastic structure layer 32, the first cavity 34 is not easily flattened or squeezed and deformed, thereby ensuring that the center wire 40 has sufficient activity space in the first cavity 34, and the center wire 40 can move smoothly (rotate or move axially) in the first cavity 34, and it is not easy to affect the branch superselection function of the center wire 40.

[0083] According to some embodiments of the present application, the elastic structure layer 32 is a metal woven mesh layer.

[0084] The metal braided mesh layer may be a mesh structure woven from metal wires. The metal braided mesh layer may play an auxiliary supporting role for the first cavity 34 , thereby reducing the probability of the first cavity 34 being flattened.

[0085] By using the elastic structural layer 32 as a metal braided layer mesh, the metal braided layer mesh encloses the first lumen 34, and the metal braided layer can provide support performance for the first lumen 34. When the connecting tube 30 bends and deforms due to adapting to the blood vessel, under the support of the metal braided layer mesh, the first lumen 34 is not easily flattened or squeezed and deformed, thereby ensuring that the center wire 40 has sufficient space for movement in the first lumen 34, which is conducive to the smooth movement of the center wire 40 in the first lumen 34 and is not easy to affect the branch superselection function of the center wire 40.

[0086] According to some embodiments of the present application, the elastic structural layer 32 is a spring. Figure 4 The schematic diagram shows a case where the elastic structural layer 32 is a spring.

[0087] By using the elastic structural layer 32 as a spring, due to the characteristics of the spring itself, the spring provides a certain elasticity and support performance to the connecting tube 30, so that the connecting tube 30 not only has a certain toughness, but also has better bending performance. After the connecting tube 30 enters the branch of the blood vessel, on the one hand, the spring can further enhance the bending performance and deformation recovery performance of the connecting tube 30, so that the connecting tube 30 can more easily adapt to the bending of the branch blood vessel and adaptively bend and deform, reducing the probability of the connecting tube 30 damaging the blood vessel. When the connecting tube 30 loses the compression effect of the blood vessel wall, the connecting tube 30 can be more easily and quickly reset under the reset effect of the spring, enhancing the bending performance and reset ability of the connecting tube 30. On the other hand, the spring encloses to form the first lumen 34. When the connecting tube 30 bends and deforms due to adapting to the blood vessel, under the support of the spring, the first lumen 34 is not easy to be flattened or squeezed, thereby ensuring that the center wire 40 has sufficient activity space in the first lumen 34, which is conducive to the smooth movement of the center wire 40 in the first lumen 34, and is not easy to affect the branch superselection function of the center wire 40.

[0088] According to some embodiments of this application, please continue to refer to Figure 4 A lubricating layer 33 is disposed on the inner side of the elastic structural layer 32 , and the lubricating layer 33 is used to reduce the friction force when the center wire 40 and the elastic structural layer 32 slide relative to each other.

[0089] The lubricating layer 33 refers to a lubricating structure disposed on the surface of the elastic structural layer 32. The central wire 40 contacts the lubricating layer 33 to reduce the friction force when the central wire 40 moves or rotates in the first cavity 34. The lubricating layer 33 can be a lubricating coating or a lubricating pipe.

[0090] By providing a lubricating layer 33 on the inner side of the elastic structural layer 32, the lubricating layer 33 contacts the center wire 40. Compared with the contact between the center wire 40 and the elastic structural layer 32, the lubricating layer 33 can reduce the friction force when the center wire 40 and the elastic structural layer 32 slide relative to each other, so that the movement of the center wire 40 in the first cavity 34 is smoother, the adjustment of the center wire 40 is smoother, and it is not easy to interfere with or hinder the elastic structural layer 32.

[0091] According to some embodiments of the present application, the lubricating layer 33 is a polytetrafluoroethylene etched tube.

[0092] PTFE is a polymer compound made of tetrafluoroethylene. It is widely used because of its excellent chemical stability, corrosion resistance, sealing, high lubricity, electrical insulation and good anti-aging resistance.

[0093] When the lubricating layer 33 is a polytetrafluoroethylene etched tube, in order to facilitate the molding of the connecting tube 30 , the lubricating layer 33 may be disposed at a position from the distal end of the connecting tube 30 to the second limiting portion 35 in the first cavity 34 .

[0094] By using a polytetrafluoroethylene etching tube as the lubricating layer 33, and compared with applying a lubricating coating on the inner wall of the first cavity 34, the polytetrafluoroethylene etching tube has better durability. In this way, the outer wall of the center wire 40 contacts the inner wall of the polytetrafluoroethylene etching tube, and the inner wall of the polytetrafluoroethylene etching tube is relatively smooth. The center wire 40 can move more smoothly in the first cavity 34, and the center wire 40 can more flexibly select the target branch blood vessel.

[0095] According to some embodiments of the present application, a connector 21 is provided at the distal end of the electrode bracket 20 , the connector 21 is embedded in the proximal end of the connecting tube 30 , and the connector 21 is hot-melt connected to the polymer material layer 31 of the connecting tube 30 .

[0096] By providing a connector 21 at the distal end of the electrode holder 20, the connector 21 acts as an intermediate transition, so that the mesh tube of the electrode holder 20 can be pre-connected with the connector 21 as a whole, and then hot-melt connected with the polymer material layer 31 of the connecting tube 30, thereby reducing the difficulty of connecting the electrode holder 20 and the connecting tube 30.

[0097] According to some embodiments of the present application, the connecting member 21 is an annular metal sheet.

[0098] By using a metal sheet as the connector 21, the metal sheet is easy to be welded and fixed to the mesh tube of the electrode holder 20, and the connection stability is good. In addition, the connector 21 is an annular structure, which facilitates the subsequent connector 21 and the elastic structure layer 32 to have sufficient welding area in the circumferential direction, and it is easy to ensure the connection strength between the elastic structure layer 32 and the connector 21.

[0099] According to some embodiments of the present application, the elastic structure layer 32 is welded to the connecting member 21 .

[0100] When the polymer material layer 31 is formed on the elastic structure layer 32, since the elastic structure layer 32 is a mesh structure or a spring with gaps, part of the material of the polymer material layer 31 will enter the gaps of the elastic structure layer 32 after hot melting, so that the elastic structure layer 32 is embedded in the polymer material layer 31, and the elastic structure layer 32 and the polymer material layer 31 are integrated.

[0101] During the assembly of the connecting tube 30, the elastic structure layer 32 can be welded to the connecting piece 21 first to achieve pre-connection of the elastic structure layer 32 and the connecting piece 21. When the polymer material layer 31 of the connecting tube 30 is subsequently hot-melted, the position of the elastic structure layer 32 is not easily changed, which is convenient for the molding accuracy of the connecting tube 30. After the elastic structure layer 32 is welded to the connecting piece 21, the installation stability of the elastic structure layer 32 in the connecting tube 30 can be further enhanced.

[0102] According to some embodiments of the present application, the inner diameter of the first cavity 34 is the same from the proximal end to the distal end, and the outer diameter of the connecting tube 30 gradually decreases.

[0103] The length of the connecting tube 30 may be 6 mm to 12 mm, and the specific size of the connecting tube 30 may be selected according to the actual situation.

[0104] From the proximal end to the distal end, the outer diameter of the connecting tube 30 is gradually reduced, and the connecting tube 30 is tapered. The distal end of the connecting tube 30 serves as a guide, which is more conducive to the connecting tube 30 entering the target branch blood vessel.

[0105] According to some embodiments of the present application, the radiofrequency ablation catheter 100 also includes a catheter 10, which is connected to one end of the electrode holder 20 away from the connecting tube 30, and the catheter 10 has a second lumen 11 extending along its axial direction, and the center wire 40 is sequentially arranged in the second lumen 11, the electrode holder 20 and the first lumen 34.

[0106] The catheter 10 refers to a tubular structure that accommodates and supports various wires and the central wire 40 of the radiofrequency ablation catheter 100. The catheter 10 can also deliver gas or liquid to the target blood vessel at the distal end. The catheter 10 can be a multi-hole tube, wherein part of the lumen of the catheter 10 is used to accommodate radiofrequency wires, thermocouple wires and other wires for achieving measurement functions, and the second lumen 11 is used to accommodate the central wire 40.

[0107] The catheter 10 can provide the function of accommodating various wires or central wire 40 of the radiofrequency ablation catheter 100. The second lumen 11 of the catheter 10 can be used for the central wire 40 to pass through. After the central wire 40 passes through the second lumen 11, the electrode bracket 20 and the first lumen 34 in sequence, the central wire 40 extends out of the connecting tube 30 to provide a branch superselection function.

[0108] According to some embodiments of this application, please refer to Figure 7 , Figure 8 and Fig. 9 The radiofrequency ablation catheter 100 further includes an operating handle 50 , which is disposed on the proximal side of the catheter 10 and connected to the proximal end of the center wire 40 to control the movement of the center wire 40 relative to the catheter 10 .

[0109] The operating handle 50 refers to an operating component disposed at the proximal end of the catheter 10 . The operating handle 50 controls the central wire 40 , and controls the rotation or axial movement of the central wire 40 .

[0110] The operating handle 50 includes a handle 51 and an operating member 52, and the handle 51 is connected to the proximal end of the catheter 10. The handle 51 has an installation cavity 511 inside, and the proximal end of the center wire 40 extends into the installation cavity 511 after passing through the catheter 10. The operating member 52 is connected to the proximal end of the center wire 40 through a fixing member 523, and the operating member 52 is movably arranged in the installation cavity 511 to realize the control function of the center wire 40, and drive the center wire 40 to move axially or rotate.

[0111] Please refer to Fig. 9 The operating member 52 may include a body 521 and a rotating handle 522. The rotating handle 522 is fixedly connected to the body 521. The body 521 is movably arranged in the installation cavity 511. The body 521 can axially move or rotate in the installation cavity 511. One side of the installation cavity 511 has an opening, and the opening allows the rotating handle 522 to extend out of the handle 51. The operator can directly act on the rotating handle 522 to drive the operating member 52 to move axially or rotate.

[0112] By setting the operating handle 50, the operating handle 50 is connected to the proximal end of the center wire 40, and the operating handle 50 plays a role in controlling the movement of the center wire 40. It can drive the center wire 40 to move axially or rotate relative to the catheter 10 according to needs, thereby realizing the distal end of the center wire 40 to rotate and explore to find the target branch blood vessel, thereby realizing the function of branch superselection.

[0113] An embodiment of the present application also provides a radiofrequency ablation device, which includes the radiofrequency ablation catheter 100 of any of the aforementioned embodiments and a control host, wherein the operating handle 50 is controlled by the operator, and can operate the central wire 40 and the electrode holder 20 to switch the working mode of the electrode holder 20 or use the central wire 40 for branch superselection, and the control host is used to control the radiofrequency ablation of the electrode holder 20, as well as perform temperature control, energy control, etc., to realize the radiofrequency ablation function.

[0114] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present application. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A radiofrequency ablation catheter, characterized in that: include: An electrode holder capable of radial contraction and expansion; A connecting tube, the proximal end of which is connected to the distal end of the electrode support, and the connecting tube has a first lumen running through the proximal end and the distal end; A central wire, movably inserted into the electrode support and the first cavity; Among them, a first limiting portion is provided on the central wire, the first limiting portion is located in the first cavity, and a second limiting portion is correspondingly provided on the inner wall of the first cavity; when the first limiting portion and the second limiting portion are abutted, and the central wire moves from the distal end to the proximal end, the electrode bracket switches from a contracted state to an expanded state.

2. The radiofrequency ablation catheter according to claim 1, characterized in that: A third limiting portion is provided on the central wire, and the third limiting portion and the first limiting portion are respectively located on two opposite sides of the second limiting portion; when the third limiting portion abuts against the second limiting portion and the central wire moves from the proximal end to the distal end, the electrode bracket can switch from the expanded state to the contracted state.

3. The radiofrequency ablation catheter according to claim 1, characterized in that: The central wire comprises a guide wire body and a soft guide wire arranged at the distal end of the guide wire body, and the first limiting portion is arranged on the guide wire body.

4. The radiofrequency ablation catheter according to claim 3, characterized in that: Along the radial direction of the soft guide wire, the soft guide wire includes an inner layer, a middle layer and an outer layer from inside to outside, the inner layer is a nickel-titanium grinding alloy wire, the middle layer is a high-density metal alloy spring, and the outer layer is a stainless steel spring.

5. The radiofrequency ablation catheter according to claim 1, characterized in that: The connecting tube comprises a polymer material layer and an elastic structure layer. The elastic structure layer is embedded inside the polymer material layer. The elastic structure layer encloses and defines the first cavity.

6. The radiofrequency ablation catheter according to claim 5, characterized in that: The elastic structure layer is a metal woven mesh layer.

7. The radiofrequency ablation catheter according to claim 5, characterized in that: The elastic structural layer is a spring.

8. The radiofrequency ablation catheter according to claim 5, characterized in that: A lubricating layer is arranged on the inner side of the elastic structural layer, and the lubricating layer is used to reduce the friction force when the central wire and the elastic structural layer slide relative to each other.

9. The radiofrequency ablation catheter according to claim 8, characterized in that: The lubricating layer is a polytetrafluoroethylene etching tube.

10. The radiofrequency ablation catheter according to claim 5, characterized in that: A connecting piece is arranged at the distal end of the electrode support, the connecting piece is embedded in the proximal end of the connecting tube, and the connecting piece is connected to the polymer material layer of the connecting tube by thermal melting.

11. The radiofrequency ablation catheter according to claim 10, characterized in that: The connecting piece is an annular metal sheet.

12. The radiofrequency ablation catheter according to claim 10, characterized in that: The elastic structural layer is welded to the connecting piece.

13. The radiofrequency ablation catheter according to claim 1, characterized in that: From the proximal end to the distal end, the inner diameter of the first cavity is the same, and the outer diameter of the connecting tube gradually decreases.

14. The radiofrequency ablation catheter according to claim 1, characterized in that: The radiofrequency ablation catheter further comprises: The catheter is connected to one end of the electrode support away from the connecting tube. The catheter has a second lumen extending along its axial direction. The center wire is sequentially arranged in the second lumen, the electrode support and the first lumen.

15. The radiofrequency ablation catheter according to claim 14, characterized in that: The radiofrequency ablation catheter further comprises: An operating handle is arranged on the proximal end of the catheter, and the operating handle is connected to the proximal end of the center wire to control the movement of the center wire relative to the catheter.

16. A radiofrequency ablation device, characterized in that: Comprising a radiofrequency ablation catheter according to any one of claims 1-15.

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