CN112294430B

CN112294430B - Radio frequency ablation catheter and preparation method thereof

Info

Publication number: CN112294430B
Application number: CN202010982505.8A
Authority: CN
Inventors: 秦翔翔; 王耀辉; 徐宏; 叶亚彬
Original assignee: Hangzhou Kunbo Biotechnology Co Ltd
Current assignee: Hangzhou Kunbo Biotechnology Co Ltd
Priority date: 2020-09-17
Filing date: 2020-09-17
Publication date: 2022-05-13
Anticipated expiration: 2040-09-17
Also published as: CN112294430A

Abstract

The application discloses a radio frequency ablation catheter and a preparation method thereof, wherein the radio frequency ablation catheter comprises a relative far end and a relative near end, and the preparation method comprises the following steps: the elastic wire and the traction wire are arranged in the inner sleeve in a penetrating mode side by side, the far ends of the elastic wire and the traction wire are fixed in advance, and the inner sleeve is thermally shrunk to obtain a stay wire assembly; an output hole and a wire guide hole are formed in the side wall of the pipe body, a fluid cavity channel and a main cavity channel are arranged in the pipe body, the output hole is communicated with the fluid cavity channel, and the wire guide hole is communicated with the main cavity channel; sleeving the electrode on the tube body, and enabling a lead connected with the electrode to enter the main cavity channel through the lead hole and extend towards the near end; butting the support sleeve with a deformation restraint tube with an inner cavity, then penetrating the support sleeve into an outer sleeve, thermally shrinking the outer sleeve to obtain a shaping component, and then penetrating the shaping component into the main cavity channel; the pull wire assembly penetrates through the inner cavity of the deformation restriction pipe, and the far end of the pull wire assembly extends out of the deformation restriction pipe until the far end part of the pipe body and is fixed.

Description

Radio frequency ablation catheter and preparation method thereof

Technical Field

The application relates to the field of medical equipment, in particular to a radio frequency ablation catheter and a preparation method thereof.

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.

At present, COPD mainly depends on drug therapy, and anticholinergic drugs are mostly used for specific blocking of M receptors to cause relaxation of airway smooth muscle, airway relaxation and reduction of mucus secretion, so that airway obstruction is relieved, and symptoms of COPD patients are relieved. 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. For example, chinese patent publication No. CN111067617A discloses a radio frequency closed catheter, which mainly includes: the heating tube comprises a tube body, a handle device, a connecting cable and a connector, wherein the tube body, the handle device, the connecting cable and the connector are sequentially connected from a far end to a near end, the tube body is sequentially provided with a rubber head, a heating section and a main tube from the far end, the surface of the heating section is provided with an insulating outer sleeve with insulating and smooth functions, a coil used for heating and formed by alloy wires in a winding mode is arranged inside the heating section, the coil comprises a near-end coil and a far-end coil, extension lines of the near-end coil and the far-end coil respectively pass through an inner cavity of the main tube and extend to the handle device, the connecting cable is connected to the connector, and the connector is connected with external equipment to provide radio-frequency current.

In the prior art, the matching relation of all parts is complex, and adverse effects are caused on production and assembly.

Disclosure of Invention

In order to solve the above technical problem, the present application discloses a method for manufacturing a radio frequency ablation catheter, the radio frequency ablation catheter including a relatively distal end and a proximal end, the method comprising:

the method comprises the following steps of (1) penetrating an elastic wire and a traction wire into an inner sleeve side by side, fixing the far ends of the elastic wire and the traction wire in advance, and thermally shrinking the inner sleeve to obtain a pull wire assembly;

an output hole and a wire guide hole are formed in the side wall of the pipe body, a fluid cavity channel and a main cavity channel are arranged in the pipe body, the output hole is communicated with the fluid cavity channel, and the wire guide hole is communicated with the main cavity channel;

sleeving an electrode on the tube body, and enabling a lead connected with the electrode to enter the main cavity channel through the lead hole and extend towards the near end;

butting a support sleeve and a deformation restraint tube with an inner cavity, then penetrating the support sleeve into an outer sleeve, thermally shrinking the outer sleeve to obtain a shaping component, and then penetrating the shaping component into the main cavity channel; and the pull wire assembly is arranged in the inner cavity of the deformation restraining tube in a penetrating way, and the far end of the pull wire assembly extends out of the deformation restraining tube until the far end part of the tube body and is fixed.

Compared with the prior art, the stay wire assembly pre-assembly can avoid the influence of the post-assembly on the motion path of the traction wire, and the optimization of the production process can improve the product assembly quality while improving the production efficiency and reducing the cost.

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 distal end portion of the elastic wire is pre-shaped into a ring shape, and when the elastic wire and the distal end of the pull wire are fixed to each other, the elastic wire and the distal end of the pull wire include:

covering a connecting cap on the far end sides of the elastic wire and the traction wire, and adjusting the traction wire to the inner side of the ring shape of the elastic wire;

filling materials are added into gaps among the connecting cap, the elastic wire and the traction wire, and the elastic wire and the traction wire are hooped by applying force to the connecting cap.

The connecting cap functions as the third-party component above and realizes the forced connection of the traction wire and the elastic wire. Connect the cap and can realize the centre gripping of elastic wire and traction wire through the deformation of self, but in order to guarantee to connect the intensity behind the cap deformation, consequently the deformation degree of connecting the cap under the conventional material selection is limited, consequently is limited to the centre gripping dynamics of elastic wire and traction wire. This problem is overcome in the present embodiment by the filler. Under the condition that the driving force for realizing the deformation of the connecting cap is the same, the filling material can increase the contact area and the holding force among the connecting cap, the elastic wire and the traction wire, thereby ensuring the connecting effect of the connecting cap.

Optionally, after the shaping assembly is inserted into the main channel, the tube body is further molded to fix the electrode.

In the assembly process of the shaping assembly, the deformation restraint tube can assist the elastic wire to keep the shape of the tube body, and can also ensure the integral shape of the main cavity, so that the inner part of the tube body in the deformation process is prevented from collapsing.

Optionally, before the molding, the method further comprises:

inserting a first liner member into the fluid delivery tube, bonding the fluid delivery tube to the proximal side of the fluid lumen;

and penetrating a second lining piece into the fluid cavity from the distal end side of the tube body.

Similar to the main channels that may be forced to collapse during the molding process, the fluid delivery tube and the fluid channels may also be forced to collapse during the molding process. The difference is that the deformation restriction pipe needs to be arranged in the main channel originally, so that the problem can be overcome by the penetration of the deformation restriction pipe. But in the fluid delivery tube and fluid channel, there is originally a fluid delivery path, so no components can be pre-assembled to overcome the collapse problem.

The first and second liner members are functionally identical and may or may not be identical in structure or size. In use, the two are brought into the molding position from different directions. In the actual entering process, the order of entering the first lining member and the second lining member may be different, and therefore, attention needs to be paid to the interference of the two.

Optionally, before the outer sleeve is heat-shrunk, a third lining member is arranged in the deformation restraining tube in a penetrating manner.

As described above, the deformation constraining tube is able to counter the tendency of the main lumen to collapse. However, the deformation constraining tube itself is an elastic component, so that the main cavity still has the possibility of being partially collapsed during the molding process. In this embodiment, the third liner inhibits collapse of the primary lumen by inhibiting collapse of the deformation constraining tube.

Optionally, the preparation method further comprises:

and the elastic piece is arranged in the elastic conduit in a penetrating manner, the far end side of the elastic conduit is connected with the deformation constraint pipe, and the far end side of the elastic conduit is fixedly bonded with the fluid conveying pipe, the elastic wire and the conducting wire.

The tube body above is mainly characterized in that the distal end of the catheter can change the size of the catheter, and the connection between the tube body and the operating handle and the penetration of each part are mainly realized through the elastic catheter in the process that the catheter enters a human body. Therefore, the elastic conduit needs to be in stressed connection with the pipe body, and a channel for the penetration of each part needs to be arranged inside the elastic conduit.

Optionally, the fluid delivery tube, the pull wire and the guide wire extend proximally through the flexible catheter.

In performance, the elasticity of the elastic conduit is provided primarily by the elastic member. The material of the elastic conduit can be the same as or different from that of the tube body.

Optionally, the preparation method further comprises:

and penetrating the conducting wire, the fluid conveying pipe and the elastic conduit into a braided pipe, thermally shrinking the braided pipe, bonding and fixing the conducting wire, the fluid conveying pipe, the elastic conduit and the braided pipe, and bonding and fixing the conducting wire, the fluid conveying pipe and the elastic conduit.

The flexible catheter is used as a main force transmission component of the radio frequency ablation catheter in the interventional process, and has the advantages of good stability, convenience in operation and assembly quality inspection.

Optionally, the preparation method further comprises:

connecting the braided tube with a handle body, and penetrating the conducting wire and the fluid conveying pipe through the handle body;

the traction wire is connected with a connecting piece, the connecting piece is installed with the handle body in a sliding mode, and a driving piece used for driving the connecting piece to slide relative to the handle body is installed on the handle body.

The application also discloses a radio frequency ablation catheter which is manufactured according to the preparation method of the radio frequency ablation catheter in the technical scheme.

The technical scheme disclosed in the application realizes the pre-assembly of each part through the optimized cooperation of each part, is convenient and efficient in the production and assembly process, can obtain a simple and stable product structure simultaneously, and has higher popularization value.

Specific advantageous technical effects will be further explained in conjunction with specific structures or steps in the detailed description.

Drawings

FIG. 1a is a schematic view of an exemplary RF ablation catheter;

FIGS. 1b and 1c are schematic views of the operation of the distal end portion of the RF ablation catheter;

FIG. 2a is a schematic view of the internal structure of a tube

FIG. 2b is an enlarged schematic view of A in FIG. 2 a;

FIG. 2c is an enlarged view of B in FIG. 2 a;

FIG. 3a is a schematic view of the structure of the outer sleeve;

FIG. 3b is an enlarged view of the point C in FIG. 3 a;

FIG. 3c is an enlarged view of D in FIG. 3 a;

FIG. 3d is a schematic structural view of a deformation constraining tube;

FIG. 3e is a schematic diagram of an electrode structure;

FIG. 4a is a schematic view of the inner sleeve structure;

FIG. 4b is an enlarged view of E in FIG. 4 a;

FIG. 4c is an enlarged view of F in FIG. 4 a;

FIG. 5a is a schematic view of an output hole in a tube;

FIG. 5b is a schematic sectional view taken along line G-G' of FIG. 5 a;

FIG. 5c is a schematic end view of the tube;

fig. 5d is an enlarged schematic view of the output aperture of fig. 5 b.

FIG. 6a is a schematic view of the engagement of the annular section of the tubular body with the braided tube;

FIG. 6b is a partially enlarged view of FIG. 6 a;

FIG. 6c is a schematic view of the inner structure of the fitting portion of the annular section and the braided tube;

FIG. 6d is a partially enlarged view of FIG. 6 c;

FIG. 7a is an exploded view of the operating handle;

FIG. 7b is a schematic view of the internal structure of the operating handle;

FIG. 7c is a schematic view of the internal structure of the operating handle from another perspective;

FIG. 7d is a schematic view of the end cap configuration;

fig. 7e is a schematic view of the end cap and driver mating.

The reference numerals in the figures are illustrated as follows:

100. a pipe body; 101. a distal end; 102. a proximal end; 103. an electrode; 1031. infiltrating the pores; 1032. welding positions; 104. an inner sleeve; 105. an outer sleeve; 106. drawing wires; 1061. drawing the outer sleeve; 107. an elastic yarn; 108. a wire; 109. a main lumen; 110. a fluid lumen; 111. an output aperture; 112. a wire guide hole; 113. a connecting cap; 114. protecting the tube; 115. an elastic conduit; 116. an elastic member; 117. weaving a tube; 118. heat-shrinkable tubing; 119. a glass sleeve; 120. a fluid delivery tube; 121. a fluid rear end delivery pipe;

200. a deformation constraining tube; 201. an annular segment; 202. a reed section; 203. a reed dredging section; 204. a threading channel; 205. supporting a tube;

300. an operating handle; 301. a handle body; 302. a connecting member; 303. mounting holes; 304. avoiding the channel; 305. a cock; 3051. a drive slot; 306. a drive member; 307. gripping the sheath; 308. a traction installation channel; 3081. a first channel; 3082. a second channel; 309. a docking channel; 311. a guide bar hole; 312. a guide key; 314. a cover body; 315. splicing the seams; 316. a positioning ring; 317. an end cap; 3171. a positioning end; 3172. a line hole.

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 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 prior art, a plurality of components such as a fluid delivery pipe for delivering a cooling medium, a lead for delivering radio frequency energy, a traction wire for operating the deformation of the annular section and the like are arranged in the radio frequency ablation catheter. Each component is typically disposed through a different lumen.

The inventor finds that the matching relation of all parts in the related technical scheme is complex, and the adverse effect is caused on production and assembly.

The application discloses a method for preparing a radiofrequency ablation catheter, the radiofrequency ablation catheter comprises a relative far end 101 and a near end 102, and the method for preparing comprises the following steps:

the elastic wire 107 and the pull wire 106 are arranged in the inner sleeve 104 in parallel in a penetrating manner, the far ends 101 of the elastic wire 107 and the pull wire 106 are fixed in advance, and the inner sleeve 104 is thermally shrunk to obtain a wire pulling assembly;

an output hole 111 and a wire guide 112 are formed in the side wall of the tube body 100, a fluid channel 110 and a main channel 109 are arranged in the tube body 100, the output hole 111 is communicated with the fluid channel 110, and the wire guide 112 is communicated with the main channel 109;

the electrode 103 is sleeved on the tube body 100, and a lead 108 connected with the electrode 103 enters the main cavity 109 through a lead hole 112 and extends towards the proximal end 102;

abutting the support sleeve with the deformation constraining tube 200 with the inner cavity, then penetrating the support sleeve into the outer sleeve 105, thermally shrinking the outer sleeve 105 to obtain a shaping component, and then penetrating the shaping component into the main cavity channel 109; the pulling wire assembly is arranged in the inner cavity of the deformation restraining tube 200 in a penetrating mode, and the far end 101 of the pulling wire assembly extends out of the deformation restraining tube 200 to the far end 101 of the tube body 100 and is fixed.

The steps in the present application may or may not be performed in sequence. For example, the wire pulling assembly and the shaping assembly are pre-assembled to obtain the corresponding components, facilitating the arrangement of the processes and the unfolding of the assembly process.

In one embodiment, the main channel 109 and the fluid channel 110 are formed by using a dual-lumen tube with an integrated structure for the tube 100, wherein one of the two channels is the fluid channel 109 and the other is the main channel 110.

In another embodiment, the main channel 109 and the fluid channel 110 are formed by nesting the tubular body 100 inside and outside, wherein the inner tube is the fluid channel 109 and the radial gap between the inner tube and the outer tube is the main channel 110.

In another embodiment, the main channel 109 and the fluid channel 110 are formed as a single piece, dual lumen tube in one portion of the tube, and a nested double lumen tube in one portion of the tube 100, wherein the inner tube interfaces with one of the dual lumen tubes to define the fluid channel 109 and the radial gap between the inner and outer tubes communicates with the other of the dual lumen tubes to define the main channel 110.

The ablation function of the distal end 101 is mainly achieved by matching the components in the main lumen 109. in a specific form, referring to an embodiment, the elastic wire 107 is pre-shaped in a ring shape at the distal end of the tube 100 and correspondingly shapes the distal end of the tube 100. in the cross section of the distal end of the tube 100, the main lumen 109 is eccentrically disposed compared to the central axis of the tube 100 and is close to the inner edge of the ring.

During the assembly of the wire assembly, the elastic wire 107 is used to maintain the shape of the pipe body 100, and the pulling wire is used to drive the deformation of the elastic wire 107 to realize the deformation of the pipe body 100. Functionally, therefore, the pull wire needs to move relative to the body 100 and the inner sleeve 104, and the elastic wire 107 may or may not be selectively fixed to the inner sleeve 104. Referring to one embodiment, the resilient wire 107 is secured to the inner sleeve 104 or the body 100. Accordingly, in another embodiment, the resilient wire 107 is provided separate from the inner sleeve 104 or the body 100. The elastic wire 107 and the traction wire 106 can be fixed by direct welding, crimping and other operations, or can be fixed by a third part. Referring to an embodiment, the portion of the distal end 101 of the elastic wire 107 is pre-shaped in a ring, and the fixing of the distal ends 101 of the elastic wire 107 and the pulling wire 106 to each other includes:

covering the connection cap 113 on the distal end 101 side of the elastic wire 107 and the pull wire 106, and adjusting the pull wire 106 to the inner side of the ring shape of the elastic wire 107;

filling material is added into the gap between the connecting cap 113, the elastic wire 107 and the pull wire 106, and the connecting cap 113 is forced to clamp the elastic wire 107 and the pull wire 106.

In this embodiment, the connection cap 113 functions as the third party part as described above, and realizes the force-receiving connection of the pull wire 106 and the elastic wire 107. The connection cap 113 can clamp the elastic wire 107 and the pull wire 106 by self deformation, but in order to ensure the strength of the connection cap 113 after deformation, the deformation degree of the connection cap 113 is limited under the selection of conventional materials, and therefore the clamping force on the elastic wire 107 and the pull wire 106 is limited. This problem is overcome in the present embodiment by the filler. Under the condition that the driving force for realizing the deformation of the connecting cap 113 is the same, the arrangement of the filling material can increase the contact area and the holding force among the connecting cap 113, the elastic wire 107 and the traction wire 106, thereby ensuring the connecting effect of the connecting cap 113. In one embodiment, the filler is a hot melt material. The filling material can change its form by heat melting, for example, from a solid phase to a liquid phase, so as to penetrate into the gaps among the connecting cap 113, the elastic wire 107 and the pulling wire 106, and when the filling material is changed back to the solid phase, the filling material can fill the gaps among the three. In one embodiment, the filler is solder. The solder has the advantages of good fluidity in liquid state, good compatibility with the elastic wire 107 and the drawing wire 106, high strength in solid state, low cost, and easy availability and satisfaction of the relevant requirements of industrial production.

The pull wire assembly also stabilizes the assembly itself by heat shrinking the inner sleeve 104. The heat shrinking of the inner sleeve 104 may effect the tightening of the elastic wire 107 and the pull wire. Thereby determining the relative position of the two. For example, the pull wire 106 is located on one side of the elastic wire 107. The inner sleeve 104 may also reduce the resistance to pull wire movement by its own material.

During the assembly of the shaping assembly, the deformation constraining tube 200 can help the elastic wire 107 to maintain the shape of the tube 100, and can also ensure the overall shape of the main lumen 109 to prevent the inner part from collapsing during the deformation of the tube 100. Referring to an embodiment, after the molding member is inserted into the main channel 109, the tube 100 is further molded to fix the electrode 103.

In this embodiment, the electrode 103 is annular and is disposed on the tube 100. Before assembly, the inner diameter of the electrode 103 is larger than that of the tube body 100, so that the sleeving of the electrode 103 and the connection of the lead 108 are conveniently realized. The die pressing of the electrode 103 is realized through the tool, the overall size or shape of the electrode 103 is changed, and the electrode 103 and the tube body 100 are fixed. Moulding subassembly wears to establish in main chamber way 109 before the mould pressing, can mode mould pressing in-process main chamber way 109 collapse, guarantees the stability of assembly.

Similar to the main channel 109 that may be forced to collapse during the molding process described above, the fluid delivery tube 120 and the fluid channel 110 may also be forced to collapse during the molding process. In contrast, the deformation restraining tube 200 is originally required to be disposed in the main channel 109, so that the problem can be overcome by inserting the deformation restraining tube 200. But in the fluid delivery tube 120 and fluid channel 110, there is inherently a delivery path for the fluid, and therefore no components can be pre-assembled to overcome the collapse problem. To overcome this problem, the fluid delivery tube 120 and the fluid delivery cavity may be filled with a fluid to maintain its shape and prevent it from collapsing during the molding process, as also referred to in one embodiment, the molding process further includes:

inserting a first liner member into the fluid delivery tube 120, bonding the fluid delivery tube 120 to the proximal end 102 of the fluid channel 110;

a second liner is inserted through the fluid channel 110 from the distal end 101 side of the tube 100.

As described above, the deformation constraining tube 200 is able to counter the tendency of the main lumen 109 to collapse. However, the deformation constraining tube 200 is itself an elastic member, so that the main channel 109 may be partially collapsed during the molding process. In one embodiment, a third liner is inserted into the deformation restraint tube 200 before the heat shrink sleeve 105. In this embodiment, the third liner inhibits collapse of the primary lumen 109 by inhibiting collapse of the deformation constraining tube 200.

In connection with the above embodiments, the first, second, and third liners function in concert to counter the tendency of the tract or member to collapse. The three are consistent or inconsistent in structure, material and size. In one embodiment, the first, second and third lining members are all nickel titanium wires. The nickel titanium material has excellent elasticity, and can avoid damage or hidden danger caused by large stress while ensuring the internal size of the cavity or the component.

In a subsequent assembly process, referring to an embodiment, the preparation method further includes:

the elastic member 116 is inserted into the elastic tube 115, the distal end 101 of the elastic tube 115 is connected to the strain restricting tube 200, and the fluid transport tube 120, the elastic wire 107, and the lead wire 108 are bonded and fixed to the distal end 101 of the elastic tube 115.

The tube 100 above focuses on the portion of the distal end 101 of the catheter that can change its size, and the connection between the tube 100 and the operating handle 300 and the penetration of the components are mainly achieved by the elastic catheter 115 during the introduction of the catheter into the human body. Therefore, the flexible conduit 115 needs to be connected to the tube 100 under stress, and a passage for each component to pass through is required to be provided inside. Referring to one embodiment, the fluid delivery tube 120, pull wire 106, and guide wire 108 extend through the flexible catheter 115 toward the proximal end 102.

In performance, the elasticity of the elastic conduit 115 is provided primarily by the elastic member 116. The flexible conduit 115 may or may not be of the same material as the tube 100.

In order to fix and assemble the components inside the elastic tube 115, referring to an embodiment, the preparation method further includes: the lead wire 108, the fluid delivery tube 120, and the elastic tube 115 are inserted into the braided tube 117, the braided tube 117 is heat-shrunk, the lead wire 108, the fluid delivery tube 120, the elastic tube 115, and the braided tube 117 are bonded and fixed, and the lead wire 108, the fluid delivery tube 120, and the elastic tube 115 are bonded and fixed.

To achieve relative movement between the pull wire 106 and the tube 100, in one embodiment, the manufacturing method further includes:

the braided tube 117 is connected with the handle body 301, and the lead 108 and the fluid delivery pipe 120 are arranged through the handle body 301;

the pull wire 106 is connected to the connector 302, the connector 302 is slidably mounted to the handle body 301, and the handle body 301 is provided with a driving member 306 for driving the connector 302 to slide with respect to the handle body 301.

In the specific arrangement of the handle, referring to an embodiment, the connecting member 302 is provided with a traction installation channel 308 penetrating through the hole wall of the installation hole 303, and the proximal portion of the traction wire 106 enters the radial gap through the traction installation channel 308; the avoidance channel 304 is disposed parallel to the hitch mount channel 308 and below the hitch mount channel 308. In the embodiment, the lower part refers to fig. 7b, the avoiding channel 304 is located below the traction installation channel 308, and the extending directions of the avoiding channel and the traction installation channel are parallel to each other, so that the pipeline can be conveniently inserted in the assembling process.

In addition to the sliding constraint of the inner wall of the handle body 301 to the connecting member 302, in an embodiment, the handle body 301 is a cylindrical structure, and the sidewall is provided with a guide bar hole 311 extending along the axial direction, the connecting member 302 is slidably mounted inside the cylindrical structure, the connecting member 302 is provided with a guide key 312 extending out of the guide bar hole 311 along the radial direction, the driving member 306 is rotatably sleeved on the periphery of the handle body 301, and the inner wall of the driving member 306 has a threaded structure matching with the guide key 312.

The guide bar holes 311 and guide keys 312 provide sliding pairs for limiting movement of the connector 302. Meanwhile, the thread structure can accurately determine the position of the guide key 312 relative to the guide bar hole 311, thereby determining the relative position of the connecting piece 302 relative to the handle body 301 and realizing the driving.

In the specific arrangement of the handle body 301, referring to an embodiment, a part of the side wall of the cylindrical structure is a detachable cover 314, the guide strip hole 311 is located at a seam 315 between the cover 314 and the rest of the cylindrical structure, and the cock 305 is located on the side of the connecting member 302 facing the cover 314.

The removable cover 314 in effect provides an access opening in the handle body 301 to facilitate assembly of the components, and similarly, the tap 305 is located on the side of the connector 302 facing the cover 314. Meanwhile, the guide strip holes 311 are formed in the abutted seam 315, so that mechanical weak areas on the handle body 301 can be reduced.

The driving force of the connector 302 comes from the rotation of the driver 306, and therefore the relative position of the driver 306 with respect to the handle body 301 needs to be determined. Referring to an embodiment, the cylindrical structure extends from its material to form a positioning ring 316 relative to the proximal side of the other portion of the cover 314, an end cap 317 is disposed on the driving member 306 and is engaged with the positioning ring 316, one end of the end cap 317 extends through the driving member 306 and is engaged with the positioning ring 316, the other end of the end cap is expanded to form a positioning end 3171, the positioning end 3171 is used for determining the relative position between the driving member 306 and the handle body 301, and a pipeline hole 3172 is disposed on the positioning end 3171.

The following is an exemplary production embodiment of the rf ablation catheter with specific operating steps and process parameters.

1. Shaping the elastic yarn 107

The elastic wire 107 in this embodiment is made of nickel titanium, and in an actual product, it is represented as a nickel titanium wire, and the operation is performed according to the following steps:

step 1, cutting a nickel-titanium wire by using a pair of cutting pliers;

winding the nickel-titanium wire on a mold core of a shaping mold, and mounting a mold sleeve;

step 3, placing the mold into a high-temperature furnace for shaping;

and 4, taking out the mold and taking down the shaped nickel-titanium wire, namely the elastic wire 107, wherein the elastic wire 107 is used for shaping the far end of the tube body 100 into the annular section 201.

2. Electrode 103 welding

Step 1, fixing an electrode 103 on an electrode clamp, placing the electrode 103 in a field area of a microscope, and adjusting the microscope to ensure that the ring electrode 103 can be seen clearly;

step 2, gently scraping the insulating layer at the distal end 101 of the lead 108 by using a blade;

step 3, dipping a proper amount of soldering flux by a solder wire, and smearing the soldering flux on a welding position 1032 of the electrode 103 (the position on the inner side of the electrode 103 where the infiltration holes 1031 are not arranged is the welding position 1032);

step 4, cutting a proper amount of solder wires, and welding the electrodes 103 and the leads 108 together by using a tool;

step 5, taking the electrode 103 from the fixture for self-inspection;

3. pull wire 106 welding

Step 1, intercepting the corresponding length of the elastic wire 107 with the number of self-winding turns of 1.25 turns, penetrating the traction wire 106 and the far end 101 of the shaped elastic wire 107 into a connecting cap 113, and adjusting the position of the traction wire 106 to enable the traction wire 106 to be positioned on the inner side of the self-winding shape of the elastic wire 107;

step 2, clamping the elastic wire 107 and the traction wire 106 on the side of the near end 102 of the connecting cap 113 by using flat tongs, cutting off a proper amount of solder wires, namely the filling material in the text, smearing the soldering flux on the far end 101 of the connecting cap 113, and welding the soldering flux on the far end 101 of the connecting cap 113;

step 3, checking whether solder flows into the proximal end 102 of the connecting cap 113, if not, welding the proximal end 102 of the connecting cap 113;

step 4, flattening the connecting cap 113 by using annular pressing pliers, and pulling the traction wire 106 and the elastic wire 107 by force to check whether the connection is firm;

step 5, cutting a proper amount of PTFE heat shrinkable film, namely the inner sleeve 104 in the above, wherein the length of the inner sleeve 104 is the same as or slightly shorter than that of the tube body 100, penetrating the traction wire 106 and the elastic wire 107 into the inner sleeve 104, and adjusting the position of the traction wire 106 to ensure that the traction wire 106 is positioned at the inner edge of the ring shape without kinking;

step 6, setting parameters of hot air equipment to be 400 ℃, clamping a hot air outlet of the connecting cap 113 by using flat tongs, keeping away from a hot air area at a corresponding position of the connecting cap 113, and thermally shrinking the inner sleeve 104 to tighten the pull wire 106 and the elastic wire 107;

and 7, penetrating the traction wire 106 into the traction outer sleeve 1061 to a position contacting with the inner sleeve 104 to obtain the pull wire assembly.

4. Die pressing

4.1 perforating the tubular body 100

Step 1, cutting a pipe body 100 with the length of 90-100 mm by using a blade;

and 2, punching on the punching machine by using the corresponding die.

4.2 mounting electrode 103

Step 1, machining a wire guide 112 on the corresponding side of an output hole 111 on a pipe body 100 by using a tool, wherein the requirement on the precision of the wire guide 112 is low, common tools such as tweezers, a drill bit, a drill point and the like can be used for machining conveniently, and the wall between a main cavity channel 109 and a fluid cavity channel 110 is not required to be punctured;

step 2, intercepting the length of the pipe body 100: the proximal end 102 side of the tube 100 is about 20mm from the first output aperture 111 (making the vertical section below the corresponding inflection point 122 in fig. 2a about 15 mm), the distal end 101 of the tube 100 is beveled to facilitate mounting of the electrode 103, and the proximal end 102 of the tube 100 is thinned to facilitate take-over;

step 3, installing the electrode 103 on the tube body 100, intercepting the length of the tube body 100: the distance between the far end 101 of the tube body 100 and the nearest electrode 103 is less than or equal to 2 mm.

4.3 Heat-shrinkable deformation constraining tube 200

Step 1, intercepting the length of a deformation restraining tube 200, wherein the deformation restraining tube 200 is made of springs with different densities made of flat wire materials, the thickness of the flat wire materials is 0.051 mm, the width of the flat wire materials is 0.3mm, the gap of the flat spring materials is 0.6mm, the length of a flat spring section 203 is 40 mm to 70mm, the length of a flat spring section 202 is 10mm to 25mm, the distance between the flat spring section 202 and a nearest electrode 103 is about 5mm to 7mm, the near end 102 of the flat spring section 202 exceeds the near end 102 of a tube body 100 by about 1mm to 2mm or is flush with the near end 102 of the tube body 100, the far end 101 of the flat spring section 203 exceeds the far end 101 of the tube body 100 by at least 15mm, and a threading channel 204 in the deformation restraining tube 200 is penetrated into a third lining member, wherein in the embodiment, the third lining member is a nickel titanium wire with the diameter of 0.6 mm;

step 2, intercepting the supporting tube 205 by about 25mm, dripping 4011 glue on the reed section 202, and penetrating the supporting tube 205 into the reed section 202 by about 10 mm;

and 3, cutting the outer sleeve 105, preferably a PTFE33# heat shrinkable tube in the embodiment, covering the sparse spring section 203 and the exposed reed section 202 in length, sleeving the outer sleeve 105 and performing heat shrinkage to obtain a shaping component, wherein the proximal end 102 of the outer sleeve 105 is subjected to heat shrinkage on the support tube 205, and the hot air equipment parameters are set to be 400 ℃.

4.4 electrode 103 embossing

Step 1, penetrating a first lining member in the fluid conveying pipe 120, wherein the first lining member is preferably a nickel-titanium wire with the diameter of 0.35mm in the embodiment;

step 2, penetrating the fluid delivery pipe 120 into the near end 102 of the fluid cavity 110 by about 8mm, dripping 4011 glue on the fluid cavity 110, penetrating the fluid delivery pipe 120 by about 2mm, and wiping the 4011 glue;

step 3, penetrating the deformation restriction tube 200 into the main cavity 109 of the tube body 100 from the proximal end 102, after the joint of the support tube 205 and the outer sleeve 105 penetrates into the main cavity 109, dropwise adding and smearing 4011 glue on the support tube 205, continuously penetrating the deformation restriction tube 200 into the main cavity 109 until the proximal end 102 of the deformation restriction tube 200 is about 1mm left compared with the proximal end 102 of the main cavity 109 or is flush with the proximal end 102 of the main cavity 109, and wiping off the surface glue;

step 4, threading a second lining member, preferably a nickel titanium wire with a diameter of 0.3mm in this embodiment, from the distal end 101 of the fluid channel 110, taking care not to push out the first lining member in the fluid delivery tube 120, and placing the tube body 100 into a molding press for molding;

step 5, taking out the pipe body 100 after mould pressing, dipping 75% alcohol by using dust-free cloth, wiping the pipe body clean, and pulling out a second lining part and a third lining part;

and 6, cutting the length of the distal end 101 of the sparse spring section 203, wherein the cutting standard is that the sparse spring section 203 is exposed out of the distal end 101 side of the pipe body 100 for about 3 circles, and peeling off the exposed part of the outer sleeve 105.

5. Braided tube 117 welding

5.1 distal end 101 fixation

Step 1, penetrating a stay wire assembly into a shaping assembly, placing a connecting cap 113 in a deformation restraint tube 200, and dropwise coating a small amount of 4011 glue and UV glue between the connecting cap 113 and the deformation restraint tube 200 for fixation;

step 2, adjusting the position of the fluid cavity 110 to ensure that the fluid cavity 110 is positioned at the annular outer edge of the tube body 100, dripping and smearing a small amount of 4011 glue outside the connecting cap 113, inserting the connecting cap 113 into the main cavity 109 of the tube body 100, dripping and smearing UV glue to fix the far end 101 side of the tube body 100, and performing gluing a small amount of times during gluing;

and 3, penetrating the protective delivery pipe 114 from the distal end 101 of the pipe body 100.

5.2 elastic conduit 115 bonding

Step 1, intercepting the elastic conduit 115 to be about 1200mm in length, penetrating the elastic member 116, exposing the elastic conduit 115 at two ends of the elastic member 116, and adhering the elastic conduit 115 at a joint by 4011 glue (the position of first adhesion is left at the handle);

step 2, cutting the far end 101 side of the elastic conduit 115 to expose the elastic part 116 by about 12mm, cutting the near end 102 side of the elastic conduit 115 to expose the elastic part 116 by about 15mm, and sleeving the elastic conduit 115 into the traction wire 106 until the elastic part 116 abuts against the deformation restraining tube 200 in the tube body 100;

and 3, adhering the exposed elastic conduit 115, the fluid delivery pipe 120, the elastic wire 107 and the conducting wire 108 firmly by using UV glue (a small amount of glue is applied, and the whole part is covered so as to prevent the glue from entering the braided tube 117 too much).

5.3 braided tube 117 welding

Step 1, cutting out a braided tube 117 by contrasting an elastic conduit 115, wherein the length of the braided tube 117 is satisfied that the elastic conduit 115 is exposed;

step 2, flaring the non-woven network section of the woven pipe 117 by using a flaring tool;

step 3, straightening the conducting wire 108, the fluid conveying pipe 120 and the elastic conduit 115, and penetrating the conducting wire, the fluid conveying pipe and the elastic conduit into a braided pipe 117;

step 4, penetrating the heat-shrinkable sleeve 118 and the glass sleeve 119 into the braided tube 117 for heat-shrinking, wherein the parameters of hot air equipment are set to be 270 ℃; wherein the heat shrinkable sleeve 118 is 14# FEP heat shrinkable tube;

step 5, scraping the near end 102 of the braided tube 117 rough by a blade, firstly adhering the guide wire 108, the fluid delivery pipe 120, the elastic catheter 115 and the braided tube 117 together by 4011 glue, and then adhering by UV (ultraviolet) glue;

step 6, the exposed lead 108, the fluid delivery tube 120, and the spring tube are glued together with UV glue at a location not exceeding the flexible conduit 115.

6. Handle assembly

Step 1, cutting 1 section of heat-shrinkable tube with the diameter of about 70mm, heat-shrinking the heat-shrinkable tube at the near end 102 of the braided tube 117, and wrapping UV glue applying points;

step 2, intercepting 2 sections of 20-25 mm RE heat-shrinkable tubes, 1 section of a fluid rear-end conveying pipe 121 with the length of 100mm and 1 section of a fluid rear-end conveying pipe 121 with the length of 80mm, coaxially heat-shrinking the 2 sections of blue heat-shrinkable tubes at the near end 102 of the fluid rear-end conveying pipe 121 with the length of 100mm, and setting parameters of hot air equipment to be 120 ℃;

step 3, penetrating the 2 sections of the fluid rear-end conveying pipes 121 into a handle tail cap, namely the end cap 317, and fixing the fluid rear-end conveying pipes by using UV glue (a pipeline hole 3172 for penetrating the 100 mm-long fluid rear-end conveying pipe 121 is formed in the middle of the handle tail cap);

step 4, a locking cap and a handle shell at the distal end 101 of the handle penetrate into the braided tube 117;

step 5, installing the cock 305 into the installation hole 303, peeling off the exposed traction outer sleeve 1061, sequentially penetrating the traction wire 106 into the first channel 3081, the butt joint channel 309 and the second channel 3082, penetrating the fluid conveying pipe 120 and the lead 108 into the avoidance channel 304, rotating the driving groove 3051 on the cock 305 by using a tool, realizing the dislocation of the traction installation channel 308 and the butt joint channel 309, and realizing the installation of the traction wire 106; during adjustment, the cock 305 applies force to the pull wire 106, thereby causing the movement of the connector 302, so this step is also the adjustment of the position of the connector 302, namely, the position of the connector 302 is adjusted by rotating the cock 305 with a tool (the connector 302 cannot be located at the limit position of the self movement stroke before the adjustment) and the bending stroke is adjusted, and after the adjustment, the proximal end 102 side of the pull wire 106 is cut off and the cock 305 is fixed by 4011 glue;

step 6, continuously installing other handle components such as a holding sheath 307 and the like, and fixing a tail cap of the handle by 4011 glue;

step 7, sealing the proximal end 102 of the fluid delivery tube 120 by using UV glue, pulling out the first lining part, cutting off the fluid delivery tube 120 and installing a luer connector;

and 8, connecting the lemo joint with a lead and fixing the lemo joint with a fluid rear-end conveying pipe 121 with a RE heat shrinkable tube in a heat shrinkage mode.

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. Features of different embodiments are shown in the same drawing, which is to be understood as also disclosing combinations of the various 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.

Claims

1. A method of making a radio frequency ablation catheter comprising opposite distal and proximal ends, the method comprising:

the elastic wire and the traction wire are arranged in an inner sleeve in a penetrating mode side by side, the far ends of the elastic wire and the traction wire are fixed in advance, the inner sleeve is thermally shrunk, and the elastic wire and the traction wire are tightened by the thermal shrinkage of the inner sleeve to obtain a pull wire assembly;

2. The method for preparing a radio frequency ablation catheter according to claim 1, wherein the distal end portion of the elastic wire is pre-shaped into a ring shape, and the fixing of the distal ends of the elastic wire and the pulling wire to each other comprises:

3. The method of claim 1, wherein the shaping element is inserted into the main lumen and the tube is further molded to secure the electrode.

4. The method of making a radio frequency ablation catheter according to claim 3, further comprising, prior to molding:

inserting a first liner member into the fluid carrying tube, bonding the fluid carrying tube at a proximal side of the fluid lumen;

5. The method of claim 4, wherein a third liner is inserted into the deformation restraining tube prior to heat shrinking the outer sleeve.

6. The method of manufacturing a radio frequency ablation catheter according to claim 1, further comprising:

7. The method of making a radio frequency ablation catheter according to claim 6, wherein the fluid delivery tube, the pull wire, and the guide wire extend proximally through the flexible catheter.

8. The method of manufacturing a radio frequency ablation catheter according to claim 6, further comprising:

9. The method of making a radio frequency ablation catheter according to claim 8, further comprising:

10. A radio frequency ablation catheter made by the method of making a radio frequency ablation catheter according to any of claims 1 to 9.