CN211934271U - Radio frequency ablation catheter and radio frequency ablation system for implementing pulmonary nerve ablation - Google Patents

Abstract

The application discloses a radiofrequency ablation catheter and a radiofrequency ablation system for performing pulmonary nerve ablation, wherein the radiofrequency ablation catheter comprises a core tube assembly and a plurality of electrodes mounted on the core tube assembly, the core tube assembly comprises a core tube, the distal end part of the core tube is an expansion part, the expansion part has a loading state and an expansion state which are opposite, the expansion part in the expansion state is in a closed or open ring shape, and the plurality of electrodes are arranged on the expansion part at intervals; and a conveying channel is further arranged in the core tube assembly, one end of the conveying channel is used for being connected with a cooling medium conveying device, and the other end of the conveying channel extends to the expansion part and is provided with an output port for each electrode independently. The technical scheme that this application is disclosed has realized that the breathing pipeline of core pipe subassembly to different positions, form can both realize stable, convenient, accurate ablation operation through the setting of inflation portion, has improved the efficiency of operation and the effect of treatment.

Description

Radio frequency ablation catheter and radio frequency ablation system for implementing pulmonary nerve ablation

Technical Field

The application relates to the field of interventional therapy, in particular to a radio frequency ablation catheter and a radio frequency ablation system for carrying out pulmonary nerve ablation.

Background

Chronic Obstructive Pulmonary Disease (COPD) is the most common Disease of the respiratory system, and has been shown in our country to be around 10% in adults over 40 years of age, based on current epidemiological survey evidence.

Currently, COPD mainly depends on drug therapy, and most of the drugs are anticholinergic drugs for specific blocking of M receptors, which causes relaxation of airway smooth muscle, airway relaxation and reduction of mucus secretion, thereby alleviating airway obstruction and relieving symptoms of COPD patients, while ablation of pulmonary denervation Therapy (TLD) pulmonary denervation therapy aims at parasympathetic nerves, blocks the dominant action thereof, and achieves permanent anticholinergic action. This approach has completed a feasible clinical study in 2015, and further clinical trials are currently underway.

With the continuous improvement of society on COPD and the continuous development of interventional technology, the treatment of chronic obstructive pulmonary disease through airway interventional technology has gained various recognition, and TLD as one of the treatment methods has the advantages of more thorough and more efficient treatment compared with the drug treatment. Therefore, the development of the TLD ablation catheter and the matched equipment thereof is planned to provide technical support for a new method for treating the chronic obstructive pulmonary disease.

As a new trend in recent years to treat COPD, TLD ablation is required to ablate the parasympathetic nerves around the main bronchi, block their innervation, achieve permanent anticholinergic effects, reduce airway smooth muscle tone, reduce mucus secretion, and improve clinical symptoms of chronic obstructive pulmonary disease.

In the ablation process, the inner wall of the main bronchus needs to be ablated in a ring shape, and an ablation point forms a closed ring on the inner wall of the main bronchus, so that effective blocking can be performed.

The inventor finds that most of the ring-shaped catheters in the related technology are electrophysiology mapping catheters, and most of the ablation catheters are single-pole ablation catheters, so that multiple ablations are needed in the treatment process, and the ablations form a closed ring, so that the operation process is complicated, and the treatment effect is not easy to control. The ablation degree is insufficient, and the ablation points are not easy to form a closed ring and are difficult to effectively block; the degree of ablation is excessive, the injury is too large, and the recovery process of the patient is not favorable.

Meanwhile, the internal cavity diameter of the breathing pipeline is gradually reduced along with the deep intervention, the form of the ablation electrode in the related technology is relatively determined, the adaptability to different arranged target tissues is poor, the ablation position is too high easily, excessive nerve inactivation is caused, and the influence on a patient is large.

SUMMERY OF THE UTILITY MODEL

In order to solve the above problems, the present application discloses a radiofrequency ablation catheter for performing pulmonary nerve ablation, comprising a core tube assembly and a plurality of electrodes mounted on the core tube assembly, wherein the core tube assembly comprises a core tube, a distal end portion of the core tube is an expansion portion, the expansion portion has a loading state and an expansion state which are opposite to each other, the expansion portion in the expansion state is in a closed or open ring shape, and the plurality of electrodes are arranged on the expansion portion at intervals;

and a conveying channel is further arranged in the core tube assembly, one end of the conveying channel is used for being connected with a cooling medium conveying device, and the other end of the conveying channel extends to the expansion part and is provided with an output port for each electrode independently.

Several alternatives are provided below, but not as an additional limitation to the above general solution, but merely as a further addition or preference, each alternative being combinable individually for the above general solution or among several alternatives without technical or logical contradictions.

Optionally, the core tube is provided with a plurality of channels, one of the channels is a first channel and serves as the conveying channel, and the output ports are formed in the side wall of the core tube and are communicated with the first channel.

Optionally, the electrode is sleeved at the corresponding output port, and a plurality of infiltration holes communicated with the corresponding output ports are formed in the electrode.

Optionally, the outer wall of the core tube is provided with a distribution groove communicated with the output port, and the cooling medium from the output port is supplied to the infiltration holes on the corresponding electrodes through the distribution groove.

Optionally, one of the plurality of channels is a second channel, each electrode is connected to a first lead, and each first lead penetrates through the sidewall of the core tube, enters the second channel, and extends to the proximal end.

Optionally, a plastic part is arranged in the core tube, and the plastic part is used for keeping the posture of the expansion part in an expansion state; the installation positions of the plastic parts are as follows:

the core pipe is fixedly arranged on the inner wall of the core pipe in a penetrating way;

or the core tube is fixed in the interlayer of the wall of the core tube in a penetrating way;

or is adhered and fixed on the outer wall of the core tube.

Optionally, the expansion part is in an open ring shape, one end of the expansion part is a tail end, the other end of the expansion part starts, and the starting end is connected with other parts of the core pipe; the part of the expansion part adjacent to the tail end is a regulation section, the rest parts are working sections, and the electrodes are distributed on the working sections and avoid the regulation section.

The application also discloses a radio frequency ablation system, which comprises a radio frequency ablation catheter, a protective tube sleeved on the radio frequency ablation catheter in a sliding manner, and a handle connected to the near end of the radio frequency ablation catheter, wherein the radio frequency ablation catheter is the radio frequency ablation catheter, and an expansion part of the radio frequency ablation catheter can be contained in the protective tube;

and the handle is provided with a pipeline joint communicated with the delivery channel and a circuit joint connected with a circuit element in the radiofrequency ablation catheter through a lead.

Optionally, the radiofrequency ablation catheter further includes a pull wire for changing the posture of the expansion part, the handle is provided with a pull wire adjusting mechanism connected with the pull wire, and the pull wire adjusting mechanism includes:

a guide fixedly connected relative to the handle;

the traction piece is connected with the pull wire and is arranged on the guide piece in a sliding manner;

and the force application part is in running fit with the guide part and drives the traction part to do linear reciprocating motion in a rotating mode.

Optionally, the rf ablation system further includes a generator connected to each electrode in the rf ablation catheter to send a corresponding energy release driving signal, and a cooling medium delivery device for respectively providing a cooling medium to the plurality of electrodes.

This application has realized through the setting of inflation portion that core pipe subassembly can both realize stable, convenient, accurate the operation of melting to different positions, the breathing pipe of form, has improved the efficiency of operation and the effect of treatment.

Specific advantageous effects will be explained in the detailed description in conjunction with specific examples.

Drawings

FIGS. 1 a-1 c are schematic views of an exemplary RF ablation catheter;

FIGS. 2a to 2b are schematic views showing changes of the annular expansion part;

FIGS. 3a to 3b are schematic views showing the detailed arrangement of the annular expansion part;

FIG. 4 is a schematic view of a wetting hole on an electrode;

fig. 5 a-5 c are schematic views of a portion of a handle of a radiofrequency ablation system in one embodiment.

The reference numerals in the figures are illustrated as follows:

1. a core tube assembly; 11. an expansion part; 113. a first channel; 114. a second channel; 115. an end cap; 12. a core tube; 13. A delivery protection pipe 131 and an output port; 14. a control segment; 2. an electrode; 51. infiltrating the pores;

6. a stress relief tube; 61. a handle; 611. a pipe joint; 612. a circuit connector; 613. a threading channel; 614. an elastic clamping jaw; 615. tightening the nut; 62. a guide member; 621. a guide port; 63. a traction member; 631. a traction body; 632. a radial rod; 633. an anchor head; 634. avoiding the through hole; 64. a force application member; 641. a helical groove.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. When a component is referred to as being "disposed on" another component, it can be directly on the other component or intervening components may also be present. Unless defined otherwise, all technical and scientific terms used herein

The words have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the present application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In the embodiment disclosed with reference to fig. 1a to 1c, the present embodiment discloses a radiofrequency ablation catheter for performing pulmonary nerve ablation, comprising a core tube assembly 1 and a plurality of electrodes 2 mounted on the core tube assembly 1,

the distal end of the core tube assembly 1 is an expansion 11, the expansion 11 having opposite loaded and expanded states; a plurality of electrodes 2 are arranged at intervals on the expansion part 11;

a conveying channel is further arranged in the core tube assembly 1, one end of the conveying channel is used for connecting a cooling medium conveying device, and the other end of the conveying channel extends to the expansion part 11 and is provided with an output port 131 for each electrode 2.

The rf ablation catheter in this embodiment is entered through the bronchoscope through the airway to the target site. The respiratory tract has larger difference compared with other interventional paths, and the cavity diameter of other interventional paths has less change degree; while the airway lumen diameter varies to a greater extent. Therefore, the radiofrequency ablation catheter realizes treatment of different target positions through the core tube assembly 1 provided with the expansion part 11. The expansion part 11 can change the self-loop diameter, so that the electrode 2 arranged on the expansion part 11 is stopped at the position close to the target point to match respiratory tracts with different cavity diameters.

The expansion part 11 in the expanded state is annular, and may be pre-shaped by heat treatment, for example, and the diameter of the annular ring may be further adjusted in some embodiments, and when the expansion part 11 is in the loaded state, the annular ring is further deformed and straightened, so as to facilitate intervention and transportation.

During ablation, a cooling medium needs to be delivered. The cooling medium can prevent the target tissue from being over-heated in the ablation process to influence the treatment effect. In the embodiment, the output ports 131 are designed independently for the plurality of electrodes 2, so that the ablation parameters of the plurality of electrodes 2 can be controlled independently. The electrodes 2 are provided with independent output ports 131, so that a structural basis can be provided for independently controlling ablation parameters by the single electrode 2, and better ablation effect can be achieved.

During the ablation procedure, the ablation status of the electrode 2 and the extent of ablation need to be controlled by a number of parameters. In one embodiment, the radiofrequency ablation catheter further comprises a plurality of temperature sensors, each temperature sensor being applied against or embedded in a respective electrode 2.

The temperature is a parameter which is easier to observe in the ablation operation and is directly related to the ablation process, and the ablation degree and the process can be directly controlled through the temperature sensor. The temperature sensor is attached to or embedded in the electrode 2, so that the ablation state of the electrode 2 can be detected more accurately. Meanwhile, the electrodes 2 are provided with temperature sensors independently, and a structural basis is provided for independently controlling the ablation parameters of the electrodes 2.

Besides natural diffusion when the cooling medium diffuses to the target point, the electrode 2 body may be provided with a plurality of wetting holes 51 communicating with the output port 131, and the cooling medium from the output port 131 is distributed to the periphery of the electrode 2 through the wetting holes 51. The cooling medium enters the electrode 2 from the delivery pipe and flows into the electrode 2 from the delivery port of the inner pore passage of the electrode 2, and flows out from the infiltration hole 51, and a thin cooling medium film in a water film form is formed on the outer surface of the electrode 2, so that the surface of the electrode is infiltrated by the cooling medium (in the embodiment, the cooling medium is physiological saline), the scab of the ablation tissue is further avoided, and the loop impedance is reduced. Maintaining impedance balance allows the ablation process to continue until the target ablation volume is reached.

The pore size and density distribution of the wetting holes 51 can be set according to the flow demand of the heat exchange medium, so as to ensure that a uniform protective film is formed on the periphery of the electrode as much as possible, for example, all the wetting holes 51 have the same pore size, or are set according to the flow balance of the heat exchange medium.

I.e., the size of the wetting holes 51 in different areas can be varied to accommodate the need for uniform flow. In the same way, the distribution density of all the wetting holes 51 at different parts of the electrode 2 is the same, or the wetting holes are correspondingly arranged according to the flow balance of the heat exchange medium.

When the heat exchange medium flow rate is balanced and correspondingly set, the arrangement mode of the heat exchange medium flow channel outlet is mainly considered, for example, the aperture of the wetting hole 51 increases with the distance from the outflow hole.

Similarly, for example, the distribution density of the wetting holes 51 increases with distance from the outlet holes.

The wetting holes 51 may be arranged as desired during processing, for example, in one embodiment, the wetting holes 51 are distributed in a plurality of groups in the circumferential direction of the electrode 2.

In the embodiment disclosed with reference to figures 2a to 2b, the core tube assembly 1 comprises a core tube 12 and the distal portion of the core tube 12 constitutes an expansion 11, the expansion 11 being in the form of a closed or open ring in the expanded state;

the electrodes 2 are arranged at intervals on the expanded portion 11 in the extending direction of the core tube 12.

Referring to fig. 2 a-2 b, the ring sizes are compared. The annular shape has an advantage in that the size of the annular shape itself can be changed to realize the function of the expansion part 11. Because the stress direction of the self deformation of the annular expansion part 11 is radial on the section of the far end, the bending of the core pipe assembly 1 in the intervention process cannot be influenced, the respiratory tract position with smaller cavity diameter can be more conveniently entered, and the fine operation is convenient. Meanwhile, the expansion part 11 may be formed by bending the distal end of the core tube 12, and the entire structure is more complete.

The 11 circle footpaths of annular inflation portion are little, can realize the respiratory tract ablation of different chamber footpaths, and self deformation stress is little, and the implementation of convenient intervention process can realize more accurate ablation. Therefore, the design scheme disclosed by the application can be adjusted as required according to different treatment scenes and use requirements, the adaptability of the radiofrequency ablation catheter is improved, and the user experience is improved.

In the embodiment disclosed with reference to fig. 3a, the core tube 12 has a plurality of channels, one of which is the first channel 113 and serves as a conveying passage, and the output ports 131 are formed in the sidewall of the core tube 12 and are all communicated with the first channel 113.

The core tube 12 can function to protect the transport path. The core tube 12 is made of a material having high strength, and can effectively avoid the cooling failure caused by the rupture of the conveying channel. Meanwhile, because the expansion part 11 and the core tube 12 can adopt an integrated design, the cooling medium is directly transmitted to the vicinity of the electrode 2 from a conveying channel in the core tube 12, and the structure is simple and stable.

In one embodiment, the electrode 2 is sleeved on the corresponding output port 131, and a plurality of wetting holes 51 communicated with the corresponding output ports are formed on the electrode 2.

Besides natural diffusion when the cooling medium diffuses to the target point, the diffusion effect can be improved by designing the output ports 131 more frequently. In this embodiment, the cooling medium at the output port 131 is better diffused to the target point through the plurality of infiltration holes 51, especially between the contact surface of the electrode 2 and the target point, so as to optimize the ablation effect, prevent the tissue from scabbing in the ablation process, and facilitate the control of the ablation process.

In one embodiment, each electrode 2 is a cylindrical shape closed in the circumferential direction or a C-shape partially opened.

The electrode 2 is fixed to the expansion portion 11 and needs to have a certain strength. In some treatment scenarios, adhesion may occur between the electrode 2 and the ablated tissue, and the electrode 2 is subjected to a pulling force when the rf ablation catheter is moved. The cylindrical or C-shaped electrode 2 can ensure the structural strength and avoid the accidental situations such as the falling off of the electrode 2. Meanwhile, the C-shaped electrode 2 also has the advantage of convenience in installation, can reduce the production cost, and can be applied to products in some treatment scenes.

In one embodiment, the outer wall of the core tube 12 is provided with a distribution groove (not shown) communicating with the output ports 131, through which the cooling medium from the output ports 131 is supplied to the wetting holes 51 on the respective electrodes 2.

The function of the distribution groove is to pre-distribute the cooling medium, thereby improving the diffusion effect of the cooling medium. If the cooling medium is simply supplied to the wetting holes 51 through the output ports 131, more cooling medium may be obtained for the wetting holes 51 of the output ports 131, and the cooling medium diffusion effect may be poor. In an actual product, the distribution groove can be operated by changing the shape of the output opening 131.

The electrode 2 requires proximal delivery of radio frequency energy during ablation. Wires need to be arranged on the core tube 12. In the embodiment disclosed in fig. 3a, one of the plurality of channels is a second channel 114, and each electrode 2 is connected to a first lead wire, which extends through the sidewall of the core tube 12 into the second channel 114 and extends proximally.

The first wire is protected by the core tube 12 so as to avoid friction with the respiratory tract affecting the stability of the wire, which is important in the interventional field and often directly affects the efficacy of the treatment and the efficiency of the operation.

In one embodiment, the radiofrequency ablation catheter further comprises a plurality of temperature sensors, each temperature sensor being attached to or embedded in a corresponding electrode 2;

a second wire is connected to each sensor and extends proximally through the sidewall of the core tube 12 into the second lumen 114 or into a separately disposed third lumen.

The temperature is a parameter which is easier to observe in the ablation operation and is directly related to the ablation process, and the ablation degree and the process can be directly controlled through the temperature sensor. The temperature sensor is attached to or embedded in the electrode 2, so that the ablation state of the electrode 2 can be detected more accurately. Meanwhile, the electrodes 2 are provided with temperature sensors independently, and a structural basis is provided for independently controlling the ablation parameters of the electrodes 2.

In the path of the second conductive line, the second channel 114 can be selected to be shared with the first conductive line or the third channel can be configured independently, so that in some special scenarios, the rf energy of the first conductive line may interfere with the second conductive line.

In the embodiment disclosed with reference to fig. 3a, one of the plurality of channels is a wire channel for disposing a wire (not shown) connected to the expansion part 11 to change the posture of the expansion part 11, and the wire channel is shared with the second channel 114 or shared with the third channel or disposed separately.

The stay wire cavity channel and other cavity channels are shared, so that the external pipe diameter of the core pipe 12 can be effectively reduced, and the implementation of the intervention process is facilitated. At the time, the other pipelines are not moved, and the pull wire moves relative to the core tube 12, so that relative interference may be generated between the pull wire and the other pipelines, and in some scenes with high requirements on the movement precision of the pull wire, the cavity channel can be configured independently. In this embodiment, the first and second leads share a second lumen 114, and the puller wires are individually configured with puller wire lumens.

In the embodiment disclosed with reference to figure 3b, the distal end of the pull wire lumen extends to the tip of the core tube 12.

The pull wire needs to operate the expansion 11 and thus needs to extend to the distal end of the core tube 12. To avoid interference of the puller wire by other components of the rf ablation catheter or by tissue in the respiratory tract, a puller wire lumen is also disposed to the distal end of the core tube 12 to protect the puller wire. In the actual product, the swelling portion 11 is formed by the distal end portion of the core tube 12, so that the wire lumen is arranged in the core tube 12 up to the tip of the core tube 12, thereby achieving control of the tip of the swelling portion 11. In the actual product, the end of the expansion part 11 is provided with an end cover 115, and the stay wire is fixed on the end cover 115.

The deformation process of the expansion part 11 is controlled by the stay wire on one hand and is realized by the elasticity of the expansion part on the other hand. In order to ensure stability of the state transition, in an embodiment, a shaping element (not shown) is provided in the core tube 12, which shaping element is arranged to maintain the position of the expansion 11 in the expanded state.

In the free state of the stay wire, the expansion part 11 is kept in the expansion state under the action of the shaping piece, and the loop diameter is the largest in space so as to facilitate the implementation of the ablation operation; when the stay wire is tightened, the elasticity of the plastic part is overcome to drive the expansion part 11 to reduce the self space volume so as to facilitate the implementation of the intervention process, and the tightening degree of the stay wire is related to the space volume of the expansion part 11, so that the near end can accurately control the space state of the expansion part 11.

The mounting of the shaping element can be of various forms. In one embodiment, the shaping member is secured to the inner wall of the core tube 12. In one embodiment, the shaping member is inserted and fixed into the sandwich of the wall of the core tube 12. In other embodiments, the shaping member may be affixed to the outer wall of the core 12. (not shown in the figure)

The core function of the shaping piece is to drive the expansion part 11 into an expansion state and drive the electrode 2 to be close to the tissue from the target point so as to realize ablation, so that the specific installation position can be set according to the design index and the condition of the internal components of the radio frequency ablation catheter.

In one embodiment, the shaping member is a nickel titanium alloy. The nickel-titanium alloy has the characteristics of good elasticity, high stability and convenience for processing and shaping. The performance requirements of the plastic part in the embodiment are met.

Aiming at the situation that the esophagus needs to be avoided when the left and right main branches are ablated, the electrode 2 is arranged on the arrangement details of the expansion part 11, and in the embodiment disclosed by referring to fig. 3b, the expansion part 11 is in an open ring shape, one end is a tail end, the other end is a starting end, and the starting end is connected with the other part of the core tube 12; the part of the expansion part 11 adjacent to the tail end is a regulation section 14, the rest parts are working sections, and the electrodes 2 are distributed on the working sections and avoid the regulation section 14.

The expansion part 11 is in an open ring shape, and has the advantage of providing a larger deformation stroke to adapt to target points with different cavity diameters. This embodiment is implemented by the arrangement of the electrodes 2 distributed over the working section in order to avoid the esophagus. In the selection of specific parameters, in an embodiment, the central angle corresponding to the working segment is greater than or equal to 270 degrees.

When aiming at the branch in the deeper position, the side does not need to consider avoiding problem, at this moment, the electrodes 2 can be uniformly distributed on the expansion part 11, namely, the tail end part can also be provided with an electrode.

In one embodiment, there are four electrodes 2. The increase in the number of electrodes 2 is more convenient for ablation to form a closed loop, but the more lines there are in the core tube 12, the more the corresponding bending and other operations are required during intervention, and in the present embodiment, the number of electrodes 2 is preferably four when the two are combined with the requirements of the existing treatment environment.

In a specific operation process, the radiofrequency ablation catheter for implementing pulmonary nerve ablation disclosed by the application establishes an intervention passage through a bronchoscope, a sheath is arranged in the bronchoscope in advance, and after the bronchoscope reaches a focus (namely a target point), an operator straightens the expansion part 11 through the protective tube 13 to enter a loading state, so that the expansion part 11 can conveniently enter the sheath. During the course of passing through the sheath, the expansion part 11 is kept in a straightened loading state until reaching the lesion site from the distal end of the sheath. After the expansion part 11 penetrates out of the sheath tube, the self ring shape can be recovered through self deformation or stay wire drive and other forms, so that the expansion part enters an expansion state to facilitate the implementation of a treatment process.

In some embodiments, the diameter of the ring can be further adjusted by twisting the force application member 64 to drive the pull wire, so as to adjust the size of the ring diameter of the expansion part 11. While also enabling adjustment of the electrode 2 position by actuating a proximal handle. In the adjustment process, an operator can observe the expansion part 11 through a bronchoscope until the electrode 2 can be well attached to the inner wall of the focus.

Then, a cooling medium is introduced, in this embodiment, cold saline is adopted, then the radiofrequency instrument is turned on, the plurality of electrodes 2 perform ablation simultaneously (the cold saline pump should adjust the flow rate according to the ablation temperature of the radiofrequency instrument, if the temperature is higher than 60 ℃, the saline flow rate should be increased, the temperature does not exceed 60 ℃, the flow rate is kept unchanged, the saline flow rate is adjusted within the range of 3-15 ml/min), the ablation power range is 3-10W, the ablation time is 60s-120s, the bronchoscope is matched with and pumps out redundant saline in the lumen during ablation, after ablation is completed, the pull wire is tightened through the force application part 64, the loop diameter of the expansion part 11 is adjusted to conveniently adjust the ablation position, next round of ablation is performed, and finally, a closed loop is formed at the ablation point on the inner wall of the focus. If the ablation point is observed through the bronchoscope and the ablation point is not closed, the expansion part 11 is adjusted to enable one electrode 2 to be in the gap position, and the monopolar ablation is carried out until the ablation point forms a closed loop.

With reference to fig. 5a to 5c, the present application further discloses a radiofrequency ablation system for performing pulmonary nerve ablation, including any one of the radiofrequency ablation catheters in the above technical solutions, a protection tube 13 slidably sleeved on the radiofrequency ablation catheter, and a handle 61 connected to a proximal end of the radiofrequency ablation catheter, wherein the expansion portion 11 of the radiofrequency ablation catheter can be folded in the protection tube 13;

the handle 61 is provided with a tubing connector 611 which is communicated with the delivery channel, and a circuit connector 612 which is connected with the circuit elements in the radiofrequency ablation catheter through wires.

The radio frequency ablation system in the embodiment establishes the access path through the bronchoscope, the respiratory tract is greatly different from other access paths, and the change degree of the cavity paths of other access paths is less; while the airway lumen diameter varies to a greater extent. Therefore, the radiofrequency ablation catheter realizes the treatment of different target positions through the core tube assembly with the expansion part. The expansion portion is capable of changing its loop diameter, thereby matching the impedance of electrodes disposed on the expansion portion near the target site to respiratory tracts of different lumen diameters. When the protection tube 13 slides, the expansion part 11 can be stroked and stored in the protection tube, when the protection tube 13 is used, the protection tube 13 is butted with the near end of the sheath, and then the radiofrequency ablation catheter is communicated with the expansion part 11 and pushed into the sheath.

In one embodiment, the proximal end of the rf ablation catheter is further sleeved with a stress relief tube 6, the stress relief tube 6 is fixed to the handle 61 in such a manner that the handle 61 has a threading channel 613 passing through axially, the distal end of the handle 61 is provided with a plurality of elastic clamping jaws 614, and the proximal end of the stress relief tube 6 is inserted into the threading channel 613 and is tightly fixed by the plurality of elastic clamping jaws 614; the plurality of resilient clamping jaws 614 cooperate to clamp and secure the stress relief tube 6 therebetween by means of a threaded engagement of a tightening nut 615.

In one embodiment, the radiofrequency ablation catheter further comprises a pull wire for changing the posture of the expansion part, and the handle 61 is provided with a pull wire adjusting mechanism connected with the pull wire.

The function of the stay wire adjusting mechanism is to apply a pulling force to the stay wire, and the stay wire is used as a flexible component and can transmit the self pulling force to the other end, namely the expansion part. The expansion part can generate preset deformation under the action of the stay wire, so that the spatial position of the electrode at the far end is adjusted, and the requirement of ablation is met.

In one embodiment, the wire adjustment mechanism includes:

a guide 62 fixedly connected to the handle 61;

a traction member 63 connected to the wire and slidably mounted on the guide member 62;

the urging member 64 is rotationally engaged with the guide member 62, and rotationally drives the pulling member 63 to linearly reciprocate.

The force applying member 64 is formed to move in a direction of rotation of the guide member 62 by the force applying member 64, so that the force applying member 64 itself makes a linear reciprocating motion to apply a force to the wire by the pulling member 63 on the premise that the guide member 62 and the handle 61 are relatively fixed. The design has the advantage that stable acting force can not be applied to the stay wire, and more importantly, stable fine adjustment can be carried out on the acting force of the stay wire.

In one embodiment, the guiding element 62 includes a tube body, the pulling element 63 is located inside the tube body, the force applying element 64 is rotatably sleeved outside the tube body, a guiding hole 621 is formed in the tube wall and is disposed along an axis of the guiding element 62, and a portion of the pulling element 63 extends out of the guiding hole 621 and is linked with the force applying element 64.

In principle, the three components of the guiding component 62, the pulling component 63 and the force applying component 64 are required to be stably driven and not generate clamping stagnation, so that the guiding ports 621 and the like are required to be arranged to guide the moving direction of the pulling component 63, and the phenomenon that the clamping stagnation is generated in the compact space layout to influence the treatment process is avoided.

In one embodiment, the force applying member 64 has a spiral groove 641 formed on an inner wall thereof, and the portion of the pulling member 63 extending out of the guiding hole 621 is engaged in the spiral groove.

The spiral groove functions to convert the rotation of the force application member 64 into the reciprocation of the wire, and is a structure for changing the moment. The design has certain requirements on the pitch and the stroke of the spiral, and the self-locking is required to ensure that the stay wire cannot displace in the using process.

In one embodiment, the pulling member 63 includes:

a traction body 631 slidably arranged within the tube body;

a radial rod 632 fixed on the traction body 631 and extending out of the guide hole 621 to match with the spiral groove;

an anchor head 633 fixedly embedded in the traction body 631, the proximal end of the pull wire being connected to the anchor head 633.

The traction member 63 needs to have a good mechanical property as a structure for directly transmitting torque with the wire. Meanwhile, the spiral groove needs to be matched, so that the clamping condition under the stress condition cannot be generated, and the design is needed on the self shape, such as a round shape and the like.

In one embodiment, the guiding element 62 is a multi-petal structure that radially and mutually snap-fits, and at least one petal is fixed relative to the handle 61 and detachably snap-fits with the rest petals.

The multi-lobe structure can improve the stability of the installation of the two. Compared with other installation modes, the multi-petal structure also has the effect of improving the assembly precision under the condition of not improving the assembly difficulty, so that the influence on the operation process caused by some unnecessary errors can be avoided.

In one embodiment, the guide 621 is provided at the split of the adjacent petals.

The guide hole 621 is formed at the splicing portion of the adjacent petals to prevent stress concentration caused by the movement of the wire, thereby providing a smoother movement performance of the wire. The guide hole 621 of the split part of the adjacent petals is easy to realize from the aspect of processing and installation.

In one embodiment, the towing member 63 defines an evacuation passageway and an evacuation through-hole 634 for evacuating the guide wire.

The pulling element 63 acts directly on the wire and therefore needs to maintain at least a portion of the axial distribution of the wire and therefore is easily accessible to the coaxial conductors or feed channels, the provision of the through hole enables an efficient distribution of the internal structure and thus a reduction in the overall bulk.

In one embodiment, the radiofrequency ablation system further comprises a generator connected to each electrode in the radiofrequency ablation catheter for sending a corresponding energizing drive signal, and a cooling medium delivery device for providing a cooling medium to each of the plurality of electrodes.

During ablation, a cooling medium needs to be delivered. The cooling medium can prevent the target tissue from being over-heated in the ablation process to influence the treatment effect. In the embodiment, the output port 131 is designed independently for a plurality of electrodes, so that the ablation parameters of the plurality of electrodes can be controlled independently. The electrodes are provided with independent output ports 131 to provide structural basis for independent control of ablation parameters by the single electrode, so that better ablation effect can be achieved.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features. When technical features in different embodiments are represented in the same drawing, it can be seen that the drawing also discloses a combination of the embodiments concerned.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (10)

1. A radio frequency ablation catheter for carrying out pulmonary nerve ablation comprises a core tube assembly and a plurality of electrodes arranged on the core tube assembly, and is characterized in that the core tube assembly comprises a core tube, the distal end part of the core tube is an expansion part, the expansion part has a loading state and an expansion state which are opposite, the expansion part in the expansion state is in a closed or open ring shape, and the plurality of electrodes are arranged on the expansion part at intervals;

and a conveying channel is further arranged in the core tube assembly, one end of the conveying channel is used for being connected with a cooling medium conveying device, and the other end of the conveying channel extends to the expansion part and is provided with an output port for each electrode independently.

2. The rf ablation catheter for performing pulmonary nerve ablation according to claim 1, wherein the core tube has a plurality of lumens, one of which is a first lumen and serves as the delivery channel, and the output ports are formed in a sidewall of the core tube and are all communicated with the first lumen.

3. The rf ablation catheter according to claim 2, wherein the electrode is sleeved at the corresponding output port, and a plurality of infiltration holes are formed on the electrode and are communicated with the corresponding output port.

4. The rf ablation catheter for performing pulmonary nerve ablation according to claim 3, wherein the outer wall of the core tube is provided with a distribution groove communicating with the output port, and the cooling medium from the output port is supplied to the infiltration holes on the corresponding electrodes through the distribution groove.

5. The rf ablation catheter for performing pulmonary nerve ablation according to claim 2, wherein one of the plurality of lumens is a second lumen, and wherein each electrode has a respective first lead wire attached thereto, each first lead wire extending through a sidewall of the core tube into the second lumen and extending proximally.

6. The rf ablation catheter for performing pulmonary nerve ablation according to claim 1, wherein a plastic member is disposed in the core tube, the plastic member being configured to maintain the expanded portion in an expanded state; the installation positions of the plastic parts are as follows:

the core pipe is fixedly arranged on the inner wall of the core pipe in a penetrating way;

or the core tube is fixed in the interlayer of the wall of the core tube in a penetrating way;

or is adhered and fixed on the outer wall of the core tube.

7. The rf ablation catheter for performing ablation of pulmonary nerves according to claim 1, wherein the expansion portion is in the shape of an open loop, one end of which is a terminal end, and the other end of which is a starting end, and the starting end is connected to the other part of the core tube; the part of the expansion part adjacent to the tail end is a regulation section, the rest parts are working sections, and the electrodes are distributed on the working sections and avoid the regulation section.

8. The radiofrequency ablation system comprises a radiofrequency ablation catheter, a protective tube which is sleeved on the radiofrequency ablation catheter in a sliding mode, and a handle which is connected to the near end of the radiofrequency ablation catheter, and is characterized in that the radiofrequency ablation catheter is the radiofrequency ablation catheter in any one of claims 1 to 7, and an expansion part of the radiofrequency ablation catheter can be contained in the protective tube;

and the handle is provided with a pipeline joint communicated with the delivery channel and a circuit joint connected with a circuit element in the radiofrequency ablation catheter through a lead.

9. The rf ablation system of claim 8, further comprising a pull wire for changing the posture of the expansion portion, wherein the handle is provided with a pull wire adjusting mechanism connected to the pull wire, and the pull wire adjusting mechanism comprises:

a guide fixedly connected relative to the handle;

the traction piece is connected with the pull wire and is arranged on the guide piece in a sliding manner;

and the force application part is in running fit with the guide part and drives the traction part to do linear reciprocating motion in a rotating mode.

10. The rf ablation system of claim 8, further comprising a generator coupled to each electrode of the rf ablation catheter for sending a corresponding de-energizable drive signal, and a cooling medium delivery device for providing a cooling medium to each of the plurality of electrodes.

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