Radio frequency ablation catheter and radio frequency ablation system

Abstract

The invention provides a radiofrequency ablation catheter and a radiofrequency ablation system. The radiofrequency ablation catheter comprises a balloon, an inner tube, a guide wire tube, an outer sleeve and a radiofrequency electrode, the near end of the balloon is provided with a near-side tube section extending along the longitudinal axis of the balloon; the inner tube is provided with an inflation cavity and a guide wire tube penetrating cavity which are not communicated with each other, the far end of the inner tube is inserted into the near-side tube section, the inner tube is in sealed connection with the near-side tube section, and the far end of the inflation cavity is communicated with an inner cavity of the balloon; the far section part of the guide wire tube extends out of the far end of the guide wire tube penetrating cavity and extends to an inner cavity of the balloon, and the guide wire tube is in sealed connection with the guide wire tube penetrating cavity; the outer sleeve is arranged outside the inner tube in a sleeving mode, the far end of the outer sleeve is connected with the near-side tube section, a gap is formed in the joint, and a threading cavity between the outer sleeve and the inner tube is used for containing a cable; the radio frequency electrode is provided with a far-side ablation area and a near-side wiring area connected with the cable, extends to the gap from the near-side wiring area to the far-side ablation area along the threading cavity, penetrates out of the gap and then is attached to the surface of the near-side pipe section to extend to the outer surface of the balloon.

Description

Technical Field

[0001] The present disclosure relates to the technical field of medical equipment, and in particular to a radiofrequency ablation catheter and a radiofrequency ablation system. Background Art

[0002] Radio Frequency Ablation (RFA) is widely used in the medical field. Its working principle is to apply radio frequency current to the target tissue (such as tumors, heart disease lesions). When the radio frequency current flows through the target tissue, the rapid change of the electromagnetic field causes the polarized water molecules in the target tissue to move at high speed, generating heat, causing the evaporation of water in the cells and the denaturation of proteins, thereby inducing necrosis of the target tissue and achieving the purpose of treatment. Radio frequency ablation technology is used in the treatment of many diseases. For example, radio frequency energy can be used to treat abnormal pathways of electrical signal conduction in cardiac tissue to restore the normal rhythm of the heart to achieve the purpose of treating arrhythmias; the thermal effect of radio frequency can also be used to cause tissue coagulative necrosis to achieve the purpose of removing tumors; radio frequency energy can also be used to treat specific nerve areas to destroy pathological nerve conduction by generating high temperatures to achieve the purpose of treating chronic pain and neurological diseases.

[0003] At present, a common medical device that uses radiofrequency ablation technology for treatment is the radiofrequency ablation catheter, and the distal end of the radiofrequency ablation catheter is equipped with an electrode made of metal material. During treatment, the radiofrequency ablation catheter is inserted into the patient's body through a natural cavity (such as a blood vessel lumen), and the distal end of the radiofrequency ablation catheter reaches the target tissue. The electrode and the target tissue are close to discharge, and the radiofrequency current is conducted along the electrode to the target tissue. However, in actual treatment, the electrode often cannot be fully close to the target tissue, affecting the treatment effect. Summary of the invention

[0004] The embodiments of the present disclosure provide a radiofrequency ablation catheter and a radiofrequency ablation system, wherein the electrodes can make good contact with the target tissue, thereby improving the treatment effect.

[0005] According to a first aspect of the present disclosure, a radiofrequency ablation catheter is provided, comprising: an expandable balloon, an inner tube, a guide wire tube, an outer tube and a radiofrequency electrode; the proximal end of the balloon is provided with a proximal tube section extending along its own longitudinal axis direction; the inner tube is a multi-cavity structure, the inner tube has an inflation cavity and a guide wire tube insertion cavity which are not communicated with each other, the distal end of the inner tube is inserted into the proximal tube section, and the outer wall of the inner tube is sealed and connected with the inner wall of the proximal tube section, the distal end of the inflation cavity is communicated with the inner cavity of the balloon; the guide wire tube is inserted into the guide wire tube insertion cavity, and the distal section of the guide wire tube is self-guided The distal end of the wire tube insertion cavity extends out and extends to the inner cavity of the balloon, and the outer wall of the wire guide tube is sealed and connected to the wire guide tube insertion cavity; the outer sleeve is arranged outside the inner tube, the distal end of the outer sleeve is connected to the proximal tube segment and a gap is formed at the joint, and the threading cavity between the inner wall of the outer sleeve and the outer wall of the inner tube is used to accommodate the cable; the radio frequency electrode has a proximal wiring area and a distal ablation area, and the proximal wiring area is connected to the cable; from the proximal wiring area to the distal ablation area, the radio frequency electrode extends along the threading cavity to the gap, and after passing through the gap, it extends to the outer surface of the balloon along the surface of the proximal tube segment.

[0006] The radiofrequency ablation catheter of the disclosed embodiment is provided with a balloon, and uses an expandable balloon to support and carry the radiofrequency electrode. The balloon in an expanded state can make the radiofrequency electrode better attached to the target tissue, thereby facilitating improving the treatment effect. The present embodiment also uses the threading cavity between the inner wall of the outer sleeve and the outer wall of the inner tube to provide a housing space for the proximal wiring area and cable of the radiofrequency electrode, so that the connection point of the proximal wiring area and the cable is located in the threading cavity and is not exposed to the surrounding environment, so that during the operation of the radiofrequency ablation catheter for treatment, the friction between the connection point and the tissue and the like causes the possibility of disconnection of the proximal wiring area and the cable or deviation of the radiofrequency electrode to be small, so as to improve the reliability of the radiofrequency ablation catheter.

[0007] In some embodiments, the radio frequency electrode is bonded to the outer sleeve and the proximal tube section at the gap by means of a sealant, so that the gap is blocked.

[0008] In some embodiments, the central axis of the inner tube is eccentrically disposed relative to the central axis of the outer tube.

[0009] In some embodiments, the cross-sections of the inner tube and the outer tube are both circular, and the eccentricity between the inner tube and the outer tube is close to the difference between the inner diameter of the outer tube and the outer diameter of the outer tube.

[0010] In some embodiments, the central axis of the inflation lumen is further away from the central axis of the outer sleeve than the central axis of the guidewire tube penetration lumen.

[0011] In some embodiments, the RF electrode includes at least a flexible metal electrode layer, a lining layer, a first flexible conductor layer, a substrate layer and a second flexible conductor layer, which are stacked in sequence from the outer surface to the inner surface of the balloon. The lining layer and the substrate layer are flexible insulating material layers. The substrate layer is provided with a conductive through hole. The distal end of the first flexible conductor layer and the distal end of the second flexible conductor layer are connected through the conductive through hole; the portion of the flexible metal electrode layer located in the proximal wiring area is connected to the RF cable in the threading cavity, and the portions of the first flexible conductor layer and the second flexible conductor layer located in the proximal wiring area are respectively connected to the two conductive cables in the threading cavity to form a thermocouple loop.

[0012] In some embodiments, a developing portion is further provided on a surface of the distal ablation zone facing the balloon.

[0013] In some embodiments, the developing portion is a closed ring structure, the developing portion is arranged at the edge of the distal ablation zone and the configuration of the developing portion is adapted to the configuration of the distal ablation zone, or the developing portion is a plurality of developing points, and the plurality of developing points are distributed at intervals along the periphery of the distal ablation zone.

[0014] In some embodiments, the developing part is a platinum-iridium alloy material developing part, and the mass percentage of platinum in the platinum-iridium alloy material is 90%, and the mass percentage of iridium is 10%; and / or, the thickness of the developing part is greater than or equal to 0.03 mm and less than or equal to 0.07 mm.

[0015] In some embodiments, the radiofrequency ablation catheter further comprises a developing element disposed on the periphery of the distal portion and located in the inner cavity of the balloon; and / or the total thickness of the radiofrequency electrode is less than or equal to 0.2 mm.

[0016] In some embodiments, the radiofrequency ablation catheter also includes a handle, a threading tube and a plug. The proximal end of the outer sleeve is connected to one end of the handle, and the other end of the handle is connected to the distal end of the threading tube. The plug is arranged at the proximal end of the threading tube. The cable extends from the proximal end connected to the plug to the distal end connected to the proximal wiring area, along the lumen of the threading tube to the handle, and extends into the threading cavity after being routed through the internal channel of the handle.

[0017] In some embodiments, the handle includes an upper cover, a lower cover and a connecting seat, the upper cover and the lower cover are buckled together to enclose a accommodating space, a portion of the connecting seat is accommodated in the accommodating space, the connecting seat has a first port connected to the inner tube, a second port connected to the guide wire tube insertion cavity, and a side port connected to the inflation cavity, the second port and the side port are respectively connected to a Luer connector, the Luer connector connected to the second port is used for the guide wire to pass through, and the Luer connector connected to the side port is used for introducing pressurized gas.

[0018] According to a second aspect of the present disclosure, a radiofrequency ablation system is provided, comprising: a radiofrequency ablation apparatus and any one of the radiofrequency ablation catheters provided in the first aspect of the present disclosure.

[0019] These and other aspects of the disclosure will be apparent from and elucidated with reference to the embodiments described hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Further details, features and advantages of the present disclosure are disclosed in the following description of exemplary embodiments in conjunction with the accompanying drawings, in which:

[0021] Figure 1 It is a schematic diagram of the structure of a radiofrequency ablation catheter according to some embodiments of the present disclosure;

[0022] Figure 2 for Figure 1 The structural diagram at A in the middle;

[0023] Figure 3 for Figure 2 A schematic cross-sectional view of a radiofrequency ablation catheter shown in ;

[0024] Figure 4 for Figure 1 A schematic diagram of a local structure of a radiofrequency ablation catheter shown in ;

[0025] Figure 5 It is a schematic diagram of the structure of the radio frequency electrode in some embodiments of the present disclosure;

[0026] Figure 6 for Figure 1 A schematic top view of a radiofrequency ablation catheter shown in ;

[0027] Figure 7 for Figure 1 Schematic diagram of the structure of the radiofrequency ablation catheter shown in.

[0028] Description of reference numerals:

[0029] 100-RF ablation catheter;

[0030] 10-balloon; 11-proximal tube section; 12-tip section;

[0031] 20-inner tube; 21-inflatable cavity; 22-guide wire tube insertion cavity;

[0032] 30-wire guide tube; 31-developing element; 32-distal section;

[0033] 40-outer sleeve; 41-threading cavity;

[0034] 50-RF electrode; 51-distal ablation zone; 511-development zone; 52-proximal wiring zone; 53-flexible metal electrode layer; 54-backing layer; 55-first flexible conductor layer; 56-substrate layer; 561-conductive via; 57-second flexible conductor layer; 58-coating layer; 581-first window; 582-second window; 59-backing layer; 591-third window; 592-fourth window; 50a, 50b, 50c, 50d-plating layer;

[0035] 60-handle; 61-upper cover; 62-lower cover; 63-connecting seat; 64, 64a, 64b-Luer connector;

[0036] 70-threading tube;

[0037] 80-plug;

[0038] 90-cable. DETAILED DESCRIPTION

[0039] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present disclosure. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0040] As used herein, the term "about" or "approximately" for any numerical value or numerical range indicates a suitable dimensional tolerance that allows a portion or collection of multiple components to perform its intended purpose as described herein. More specifically, "about" or "approximately" can refer to a range of ±20% of the value of the recited value, for example, "about 90%" can refer to a range of values ​​from 71% to 99%.

[0041] Additionally, as used herein, the terms "patient," "host," and "user" refer to any human or animal subject, and are not intended to limit the systems or methods or uses to human use.

[0042] Figure 1 is a schematic diagram of the structure of a radiofrequency ablation catheter according to some embodiments of the present disclosure, Figure 2 for Figure 1 The structural diagram at A in the middle, Figure 3 for Figure 2 A schematic cross-sectional view of a radiofrequency ablation catheter is shown in . Figures 1 to 3The radiofrequency ablation catheter 100 comprises: a balloon 10, an inner tube 20, a guide wire tube 30, an outer tube 40 and a radiofrequency electrode 50. The balloon 10 is configured to be expandable and contractible, and a proximal tube section 11 extending along the longitudinal axis direction of the balloon 10 is provided at the proximal end thereof. The inner tube 20 is a multi-cavity structure, and the inner tube 20 has an inflatable cavity 21 and a guide wire tube insertion cavity 22 which are not connected to each other. The inflatable cavity 21 is used to transmit pressurized gas, and the distal end of the inner tube 20 is plugged into the proximal tube section 11, and the outer wall of the inner tube 20 is sealedly connected to the inner wall of the proximal tube section 11, and the distal end of the inflatable cavity 21 is connected to the inner cavity of the balloon 10. The guide wire tube 30 is penetrated in the guide wire tube insertion cavity 22, and the distal section 32 of the guide wire tube 30 extends from the distal end of the guide wire tube insertion cavity 22 and extends to the inner cavity of the balloon 10, and the outer wall of the guide wire tube 30 is sealedly connected to the guide wire tube insertion cavity 22. The outer sleeve 40 is sleeved outside the inner tube 20, the distal end of the outer sleeve 40 is connected to the proximal tube segment 11 and a gap is formed at the joint, and the threading cavity 41 between the inner wall of the outer sleeve 40 and the outer wall of the inner tube 20 is used to accommodate the cable (a single "cable" or multiple "cables" are collectively referred to as "cables 90"). The radio frequency electrode 50 has a proximal wiring area 52 and a distal ablation area 51, and the proximal wiring area 52 is connected to the cable 90. From the proximal wiring area 52 to the distal ablation area 51, the radio frequency electrode 50 extends along the threading cavity 41 to the gap, and after passing through the gap, it extends to the outer surface of the balloon 10 against the surface of the proximal tube segment 11.

[0043] In the disclosed embodiment, taking the balloon 10 as an example, the end of the balloon 10 or its components closer to the operator in the extension direction is defined as the "proximal end", and similarly, the end of the balloon 10 or its components farther away from the operator in the extension direction is defined as the "distal end". The definitions of the "proximal end" and "distal end" of the inner tube 20, the guide wire tube 30, the outer sleeve 40 and other components can all refer to the balloon 10, and will not be repeated here. The "side port" is defined as an orifice provided on the side surface of the component, and the "port" is defined as an orifice provided on the end surface of the component.

[0044] like Figure 2 and Figure 3As shown, the distal portion 32 of the guide wire tube 30 can be coaxially arranged with the balloon 10. In addition, the distal portion 32 of the guide wire tube 30 can also be designed to extend out of the inner cavity from the distal end of the balloon 10. In some optional embodiments, the radiofrequency ablation catheter 100 can also include a tip portion 12 located outside the balloon 10, the outer surface of the tip portion 12 is an arcuate surface formed by rotating around its own longitudinal axis, and the tip portion 12 is coaxially arranged and connected with the distal portion 32. In this way, the guide wire inserted into the guide wire tube 30 extends from the distal portion 32, is inserted into the tip portion 12, and then passes out from the tip portion 12. By designing the tip portion 12, and the outer surface of the tip portion 12 is smooth, not only can the resistance of its travel in the natural cavity be reduced, and the entry is smoother, but also it is conducive to reducing the possibility of the tip portion 12 damaging the patient's tissue during the push and treatment of the radiofrequency ablation catheter 100. Among them, the material of the tip portion 12 can be at least one of polyamide, polyether block polyamide, and polyurethane.

[0045] Wherein, the mode that realizes the inner wall of the outer wall of inner tube 20 and the inner wall of proximal tube section 11 is sealed and connected includes but is not limited to the following possible examples. As an example, a sealing ring can be used to be set outside the inner tube 20, and the sealing ring is used to block the gap between the outer wall of the inner tube 20 and the inner wall of the proximal tube section 11. As an example, the outer wall of the inner tube 20 and the inner wall of the proximal tube section 11 can be connected by sealant (such as, silica gel, epoxy resin, etc.). As an example, when the inner tube 20 and the proximal tube section 11 are all made of thermoplastic material, the outer wall of the inner tube 20 and the inner wall of the proximal tube section 11 can also be connected and realize sealing by hot-melt connection mode. The outer wall of the guide wire tube 30 and the guide wire tube penetrate the cavity 22 and are sealed and connected in a similar way, and this paper will not repeat them here.

[0046] When using the RF ablation catheter 100 of this embodiment for treatment, the operator folds and rolls the balloon 10 to reduce the volume of the balloon 10, then delivers the RF ablation catheter 100 into the patient's body, pushes the RF ablation catheter 100 to reach the target tissue, and then inputs pressurized gas into the inflation cavity 21. The pressurized gas flows along the inflation cavity 21 into the inner cavity of the balloon 10. The pressure in the inner cavity of the balloon 10 increases and the balloon 10 expands accordingly. The RF electrode 50 is attached to the target tissue, and then the RF energy generator of the RF ablation device is controlled to work to transmit RF current to the RF electrode 50. The RF current is applied to the target tissue through the RF electrode 50 to achieve ablation.

[0047] The radiofrequency ablation catheter 100 of the disclosed embodiment is provided with a balloon 10, and uses the expandable balloon 10 to support and carry the electrode. The balloon 10 in the expanded state can make the electrode better attached to the target tissue, thereby facilitating the improvement of the treatment effect. The present embodiment also uses the threading cavity 41 between the inner wall of the outer sleeve 40 and the outer wall of the inner tube 20 to provide a housing space for the proximal wiring area 52 and the cable 90 of the radiofrequency electrode 50, so that the connection point between the proximal wiring area 52 and the cable 90 is located in the threading cavity 41 and is not exposed to the surrounding environment, so that during the operation of the radiofrequency ablation catheter 100 for treatment, the friction between the connection point and the tissue and the like causes the possibility of disconnection of the proximal wiring area 52 and the cable 90 or deviation of the radiofrequency electrode 50 to be small, which is conducive to improving the reliability of the radiofrequency ablation catheter 100. On this basis, by designing the outer wall of the inner tube 20 to be sealedly connected to the inner wall of the proximal tube segment 11, and the outer wall of the guide wire tube 30 to be sealedly connected to the guide wire tube insertion cavity 22, the independence of the inflation cavity 21, the guide wire tube insertion cavity 22 and the threading cavity 41 can be improved, so as to reduce the possibility of pressurized gas overflowing from the gap, so as to ensure the expansion effect of the balloon 10, and thereby enable the electrode to be better attached to the target tissue.

[0048] In order to further reduce the possibility of pressurized gas escaping from the gap, in some embodiments of the present disclosure, the RF electrode 50 can also be bonded and connected to the outer sleeve 40 and the proximal tube segment 11 at the gap by means of a sealant, so that the gap is blocked. During the preparation process of the RF ablation catheter 100 of this embodiment, the guide wire tube 30 and the guide wire tube of the inner tube 20 can be first fitted into the lumen 22 and then sealed and connected, then the inner tube 20 and the proximal tube segment 11 can be fitted into each other and then sealed and connected, and then the outer sleeve 40 can be put outside the inner tube 20, and then the outer sleeve 40 and the proximal tube segment 11 can be connected.

[0049] The positional matching relationship between the inner tube 20 and the outer tube 40 is various. In some embodiments of the present disclosure, the inner tube 20 and the outer tube 40 can be coaxially arranged, and the threading cavity 41 formed between the two is annular and the size of the annular threading cavity 41 in the direction perpendicular to the longitudinal axis of the inner tube 20 is equal everywhere. As an alternative embodiment, Figure 4 As shown, the central axis of the inner tube 20 can also be eccentrically arranged relative to the central axis of the outer tube 40, wherein Figure 4 for Figure 1 The schematic diagram of the local structure of the radiofrequency ablation catheter 100 is shown in FIG. By making the inner tube 20 and the outer tube 40 non-coaxial, the size of the threading cavity 41 formed between the inner tube 20 is not equal everywhere. In this example, the threading cavity 41 is perpendicular to the longitudinal axis of the inner tube 20 in the first direction ( Figure 4 The maximum value d1 of the dimension on Y is shown in max and in a second direction perpendicular to the longitudinal axis direction of the inner tube 20 ( Figure 4The maximum value d2 of the dimension on X) is shown in max In this way, firstly, the cables 90 can be stored more centrally in the limited space of the threading cavity 41, and secondly, the threading cavity 41 can accommodate a larger proximal wiring area 52, so that the size restriction of the proximal wiring area 52 of the RF electrode 50 is relaxed.

[0050] In the case where the central axis of the inner tube 20 is eccentrically arranged relative to the central axis of the outer tube 40, further, as Figure 4 As shown, the cross-sections of the inner tube 20 and the outer tube 40 are designed to be circular, and the eccentricity ΔD of the inner tube 20 and the outer tube 40 is close to the difference between the inner diameter D1 of the outer tube 40 and the outer diameter D2 of the inner tube 20. In other words, ΔD is approximately D1-D2. The cross-section of the threading cavity 41 in this example is roughly crescent-shaped. In this way, the inner tube 20 is in contact with or close to the inner wall of the outer tube 40, and this design is conducive to making d1 max and d2 max As much as possible. Of course, in other embodiments of the present disclosure, the cross-sections of the inner tube 20 and the outer tube 40 can also be selected from any of the shapes of ellipse, rectangle, oblong, etc. In this embodiment, the cross-sectional shapes of the guide wire tube insertion cavity 22 and the inflation cavity 21 are also not limited, for example, they can be selected from any of the shapes of circle, semicircle, ellipse, rectangle, oblong, etc. As an example, Figure 4 As shown, the cross section of the guide wire tube insertion cavity 22 is circular, the cross section of the inflation cavity 21 is arcuate, and the cross section of the inflation cavity 21 has an arcuate profile and a straight profile, and the arcuate profile and the straight profile are connected to form a closed shape.

[0051] In some embodiments of the present disclosure, the central axis of the inflation cavity 21 can be configured to be farther away from the central axis of the outer sleeve 40 than the central axis of the guide wire tube penetration cavity 22. Figure 4 In the embodiment, the inflation cavity 21 is located below the guide wire tube insertion cavity 22. Compared with the case where the guide wire tube insertion cavity 22 is located below the inflation cavity 21, the present embodiment is designed in such a way that the center of gravity of the guide wire tube 30 inserted in the guide wire tube insertion cavity 22 will not be excessively offset from the center of the outer sleeve 40, and the center of gravity of the balloon 10 coaxially arranged with the distal portion 32 will not be excessively offset from the center of the outer sleeve 40, which is conducive to making the radiofrequency ablation catheter 100 have good balance and reliability.

[0052] Figure 5 FIG. 5 is a schematic diagram of the structure of the radio frequency electrode 50 in some embodiments of the present disclosure. In some embodiments of the present disclosure, as Figure 5As shown, the RF electrode 50 may at least include a flexible metal electrode layer 53, a lining layer 54, a first flexible conductor layer 55, a substrate layer 56, and a second flexible conductor layer 57 stacked in sequence from the outer surface to the inner surface of the balloon 10, and the lining layer 54 and the substrate layer 56 are flexible insulating material layers. The flexible insulating material may be polyimide (PI), polyethylene terephthalate (PET), polyurethane (PU), or a combination thereof. It can be seen that each layer of the RF electrode 50 of this embodiment is flexible, and the RF electrode 50 has good flexibility as a whole. The RF electrode 50 can be deformed as the balloon 10 expands and contracts, so that when the balloon 10 contracts, the distal end of the RF ablation catheter 100 can reach a smaller volume, which is conducive to reducing the resistance encountered during its intervention into the patient's body.

[0053] The portion of the flexible metal electrode layer 53 located in the proximal wiring area 52 is connected to the radio frequency cable 90 in the threading cavity 41 to transmit the radio frequency current to the flexible metal electrode layer 53 through the radio frequency cable 90. The substrate layer 56 is also provided with a conductive through hole 561, and the distal end of the first flexible conductor layer 55 and the distal end of the second flexible conductor layer 57 are connected through the conductive through hole 561. The portions of the first flexible conductor layer 55 and the second flexible conductor layer 57 located in the proximal wiring area 52 are respectively connected to the distal ends of the two conductive cables 90 in the threading cavity 41, and the proximal ends of the two conductive cables 90 are connected to a voltage measuring instrument (such as a voltmeter) to form a thermocouple loop. Among them, one of the first flexible conductor layer 55 and the second flexible conductor layer 57 is equivalent to the positive pole of the thermocouple, and the other is equivalent to the negative pole of the thermocouple. The thermocouple here can be any of several types that meet the requirements that both the positive electrode material and the negative electrode material can withstand a certain bending: K-type thermocouple, T-type thermocouple, J-type thermocouple, and N-type thermocouple. In this way, the temperature of the target tissue can be transmitted to the connection point between the distal end of the first flexible conductor layer 55 and the distal end of the second flexible conductor layer 57 through the portion of the flexible metal electrode layer 53 located in the distal ablation zone 51. The temperature of the connection point can be detected by utilizing the thermocouple effect, thereby enabling the temperature of the radiofrequency ablation area and the target tissue to be monitored.

[0054] It is understandable that the number of the RF electrodes 50 is not limited, and can be one or more. When the number of the RF electrodes 50 is one, such as Figures 2 to 4 As shown, the threading cavity 41 contains one radio frequency cable 90 and two conductive cables 90. When there are multiple radio frequency electrodes 50, the threading cavity 41 contains multiple radio frequency cables 90 and conductive cables 90 corresponding to the multiple radio frequency electrodes 50.

[0055] In some embodiments, the flexible metal electrode layer 53 may further include a coating layer 58 and a backing layer 59, wherein the coating layer 58 is disposed on a side of the flexible metal electrode layer 53 facing away from the backing layer 54, and the coating layer 58 is provided with a first window 581 and a second window 582, and the portion of the distal end of the flexible metal electrode layer 53 not covered by the coating layer 58 is electrically connected to the coating layer 50a formed by deposition in the first window 581, and the coating layer 50a is exposed to the surrounding environment to discharge against the target tissue, and the portion of the proximal end of the flexible metal electrode layer 53 not covered by the coating layer 58 is connected to the RF cable 90 through the coating layer 50b formed by deposition in the second window 582, and the coating layer 50b and the RF cable 90 may be connected by welding, for example. Among them, the length of the first window 581 may be, for example, 8 mm, and the width may be, for example, 4 mm, and accordingly, the size of the RF ablation area of ​​the RF electrode 50 is approximately 4 mm×8 mm. The back film layer 59 is arranged on a side of the second flexible conductor layer 57 facing away from the substrate layer 56. The back film layer 59 is provided with a third window 591 and a fourth window 592. The proximal end of the first flexible conductor layer 55 is connected to a conductive cable 90 through a coating 50c deposited in the third window 591. The portion of the second flexible conductor layer 57 not covered by the back film layer 59 is connected to another conductive cable 90 through a coating 50d deposited in the fourth window 592. Similar to the substrate layer 56 and the lining layer 54, the coating layer 58 and the back film layer 59 are also made of flexible insulating material.

[0056] On the basis that each layer of the RF electrode 50 is flexible, the total thickness of the RF electrode 50 can be configured to be less than or equal to 0.2 mm, and specifically can be any value among 0.15 mm, 0.16 mm, 0.17 mm, 0.18 mm, 0.19 mm, and 0.2 mm. With such a design, the overall thickness of the flexible RF electrode 50 is relatively small, which is conducive to further reducing the volume of the RF ablation catheter 100 when it is inserted into the human body, so as to reduce the insertion resistance.

[0057] Figure 6 for Figure 1 Schematic diagram of a top view of a radiofrequency ablation catheter 100 shown in FIG. Figure 6 As shown, a side of the distal ablation zone 51 facing the balloon 10 may also be provided with a developing portion 511. During the surgical procedure using the radiofrequency ablation catheter 100 of this embodiment, the developing portion 511 may be detected using an external image detection device (such as an X-ray detection device) so that the developing portion 511 can be visualized, thereby helping the operator to accurately locate the position of the distal ablation zone 51 of the radiofrequency electrode 50, thereby improving the surgical operation accuracy and surgical safety.

[0058] The material of the developing part 511 can be selected from one or more materials such as gold, platinum, iridium, tantalum, and tungsten. As an example, the developing part 511 can be a developing part 511 made of a platinum-iridium alloy material, and the mass percentage of platinum in the platinum-iridium alloy material is 90% and the mass percentage of iridium is 10%. On the one hand, thanks to the excellent electrical conductivity of the platinum-iridium alloy, it is beneficial to ensure that the current transmitted to the radio frequency electrode 50 can be accurately controlled. On the other hand, thanks to the good developing performance of the platinum-iridium alloy, it is beneficial to make the developing part 511 clearly visible during the operation, which is convenient for accurate positioning. The thickness of the developing part 511 can be designed to be greater than or equal to 0.03mm and less than or equal to 0.07mm, and can be any value of 0.03mm, 0.04mm, 0.05mm, 0.06mm, and 0.07mm. This embodiment makes the thickness of the developing part 511 smaller, which is beneficial to make the volume of the radio frequency ablation catheter 100 smaller when it intervenes in the human body, so as to reduce the intervention resistance.

[0059] The specific implementation methods of the developing portion 511 are various. In some embodiments of the present disclosure, the developing portion 511 can be a closed ring structure, and the developing portion 511 is arranged at the edge of the distal ablation zone 51, and the configuration of the developing portion 511 is adapted to the configuration of the distal ablation zone 51. Exemplarily, the distal ablation zone 51 is rectangular, and the developing portion 511 is a rectangular ring. It should be pointed out that the rectangle referred to herein is not limited to a right-angled rectangle, but can also be a rounded rectangle or a deformation thereof. In other embodiments of the present disclosure, the developing portion 511 can be constructed into a plurality of developing points, and the plurality of developing points are spaced apart along the periphery of the distal ablation zone 51. Exemplarily, in Figure 6 In the figure, the number of developing points is 6. Of course, the number of developing points can also be 4, 8, 10, etc., which can be designed according to needs and actual disclosure. The configuration of the developing point is not limited, for example, it can be circular, rectangular, elliptical, etc. When the developing point is circular, the diameter can be 0.7 mm. This design enables the developing part 511 to present the approximate outline and boundary of the RF electrode 50 in the image, so that the shape of the RF electrode 50 can be displayed, so that the operator can more accurately judge the position, orientation and contact of the RF electrode 50 with the target tissue, which can further optimize the treatment effect. Moreover, without changing parameters such as thickness, compared with the technical solution in which the developing part 511 is a closed ring structure, when the developing part 511 is composed of multiple developing points, less material is required for the developing part 511, which is conducive to saving material costs.

[0060] In some embodiments of the present disclosure, please continue to refer to Figure 2 and Figure 3The radiofrequency ablation catheter 100 may further include a developing element 31, which is disposed on the periphery of the distal portion 32 and is located in the inner cavity of the balloon 10. During surgery, the developing element 31 may be detected by an external imaging detection device so that the developing element 31 can be visualized, thereby helping the operator to accurately locate the position of the balloon 10, thereby ensuring that the balloon 10 is accurately located at the target tissue.

[0061] This embodiment does not impose any specific restrictions on the position and number of the developing components 31. Figure 2 and Figure 3 In the embodiment shown, the balloon 10 may specifically include a proximal conical section, a cylindrical section, and a distal conical section, the distal ablation zone 51 is attached to the outer surface of the cylindrical section, two developing elements 31 are provided, and the two developing elements 31 are spaced apart along the longitudinal axis direction of the guide wire tube 30, one developing element 31 roughly corresponds to the connection between the cylindrical section and the distal conical section, and the other developing element 31 roughly corresponds to the connection between the cylindrical section and the proximal conical section. In this embodiment, the two developing elements 31 correspond to the proximal end and the distal end of the cylindrical section, respectively, which is conducive to helping the operator to accurately locate the position of the cylindrical section, and thus can facilitate the location of the radio frequency electrode 50 located in the cylindrical section.

[0062] The total length of the balloon 10 along its longitudinal axis can be greater than or equal to 13 mm and less than or equal to 19 mm. When the balloon 10 includes a proximal conical section, a cylindrical section and a distal conical section, the length of the cylindrical section can be 9 mm, and the thickness of the balloon 10 can be greater than or equal to 0.01 mm and less than or equal to 0.04 mm.

[0063] The material of the developing element 31 may refer to the material of the developing portion 511 . Specifically, the material of the developing element 31 may also be selected from one or more materials such as gold, platinum, iridium, and tantalum.

[0064] Figure 7 for Figure 1 The schematic diagram of the structure of the radiofrequency ablation catheter 100 is shown in FIG. In some embodiments of the present disclosure, as shown in FIG. Figure 7As shown, the radiofrequency ablation catheter 100 may also include a handle 60, a threading tube 70 and a plug 80. The proximal end of the outer sleeve 40 is connected to one end of the handle 60, and the other end of the handle 60 is connected to the distal end of the threading tube 70. The plug 80 is arranged at the proximal end of the threading tube 70. The cable 90 extends from the proximal end connected to the plug 80 to the distal end connected to the proximal wiring area 52, along the lumen of the threading tube 70 to the handle 60, and extends into the threading cavity 41 after being routed in the internal channel of the handle 60. The plug 80 is used to connect the cable 90 with the radiofrequency ablation instrument, and transmit the high-frequency current generated by the radiofrequency energy transmitter to the radiofrequency cable 90. In actual use, the operator can conveniently control the radiofrequency ablation catheter 100 to intervene in the human body by holding the handle 60, and can conveniently adjust the position and direction of the radiofrequency electrode 50, so that the operation convenience is enhanced.

[0065] The handle 60 also provides a transmission channel for the cable 90, the pressurized gas, and the guide wire. Figure 7 The handle 60 may specifically include an upper cover 61, a lower cover 62 and a connecting seat 63. The upper cover 61 and the lower cover 62 are buckled together to enclose a receiving space. Part of the connecting seat 63 is accommodated in the receiving space. The connecting seat 63 has a first port connected to the inner tube 20, a second port connected to the guide wire tube insertion cavity 22, and a side port connected to the inflation cavity 21. The second port is connected to a Luer connector 64a, and the Luer connector 64a is used for the guide wire to pass through. The side port is connected to a Luer connector 64b, and the Luer connector 64b is used to pass pressurized gas. The Luer connector 64a and the Luer connector 64b are collectively referred to as Luer connector 64.

[0066] The material of the handle 60 may be polyurethane, polyethylene, acrylonitrile-styrene-butadiene copolymer or a combination thereof. The material of the Luer connector 64 may be polycarbonate, polyethylene, acrylonitrile-styrene copolymer or a combination thereof. The Luer connector 64 may be a 6% Luer connector 64, which may specifically refer to the length of the Luer connector 64 extending out of the accommodation space of the handle 60 being 6% of the total length of the handle 60.

[0067] As disclosed herein, in the radiofrequency ablation catheter 100, the balloon 10 may be a single-layer structure or a multi-layer structure, and each layer is stacked in sequence along the thickness direction of the balloon 10. The balloon 10 may be a non-compliant balloon, and the material of any layer of the balloon 10 may include one or more materials such as polyamide, polyether block polyamide, polyurethane, polyethylene terephthalate, and polyvinyl chloride. In this embodiment, by making the balloon 10 a non-compliant balloon, when the pressure in the inner cavity of the balloon 10 is within a preset range, the balloon 10 can maintain a stable size and volume, that is, the size of the balloon 10 can be more accurately controlled. In this way, the size of the balloon 10 is stable during the treatment process, so that the electrode can be stably attached to the target tissue, which is conducive to improving the stability of the treatment effect. Moreover, the non-compliant balloon will not expand easily when inflated, so it can avoid excessive expansion of the balloon 10 to cause other injuries, reducing the risk in treatment.

[0068] As disclosed herein, in the radiofrequency ablation catheter 100, the material of the inner tube 20 may be at least one of polyamide, polyether block polyamide, and polyurethane. The outer sleeve 40 may be a braided tube, and the main material of the braided tube may be polyamide, polyether block polyamide, polyurethane, or a combination thereof, and the material of the braided wire of the braided tube may be stainless steel. Thus, the outer sleeve 40 has high strength, good flexibility, and torsion control performance, so that the outer sleeve 40 can be suitable for application scenarios where frequent twisting is allowed, and can effectively reduce damage and aging.

[0069] The disclosed embodiment further provides a radiofrequency ablation system, including a radiofrequency ablation apparatus and a radiofrequency ablation catheter 100 according to any of the aforementioned embodiments, wherein a plug 80 of the radiofrequency ablation catheter 100 is connected to the radiofrequency ablation apparatus.

[0070] It should be understood that in this specification, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships or dimensions that are based on the orientations or positional relationships or dimensions shown in the accompanying drawings, and these terms are used only for the convenience of description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the scope of protection of the present disclosure.

[0071] In addition, the terms "first", "second", "third", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", "third" may explicitly or implicitly include one or more of the feature. In the description of the present disclosure, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0072] In the present disclosure, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0073] In the present disclosure, unless otherwise expressly specified and limited, a first feature being “above” or “below” a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being “above”, “above”, and “above” a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0074] This specification provides many different embodiments or examples that can be used to implement the present disclosure. It should be understood that these different embodiments or examples are purely exemplary and are not intended to limit the scope of protection of the present disclosure in any way. Those skilled in the art can conceive of various changes or replacements based on the disclosure of the present specification, which should all be included in the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure should be based on the scope of protection defined by the attached claims.

Claims

1. A radiofrequency ablation catheter, characterized in that: include: The balloon is expandable and deflable, and the proximal end of the balloon is provided with a proximal tube section extending along the longitudinal axis direction of the balloon; The inner tube is a multi-lumen structure, the inner tube has an inflation cavity and a guide wire tube insertion cavity which are not communicated with each other, the distal end of the inner tube is inserted into the proximal tube segment, and the outer wall of the inner tube is sealed and connected with the inner wall of the proximal tube segment, and the distal end of the inflation cavity is communicated with the inner cavity of the balloon; A guide wire tube is inserted into the guide wire tube insertion cavity, a distal portion of the guide wire tube extends from the distal end of the guide wire tube insertion cavity and extends to the inner cavity of the balloon, and an outer wall of the guide wire tube is sealed and connected to the guide wire tube insertion cavity; An outer sleeve is sleeved outside the inner tube, the distal end of the outer sleeve is connected to the proximal tube section and a gap is formed at the joint, and a threading cavity between the inner wall of the outer sleeve and the outer wall of the inner tube is used to accommodate cables; A radio frequency electrode having a proximal connection area and a distal ablation area, wherein the proximal connection area is connected to the cable; From the proximal wiring area to the distal ablation area, the radio frequency electrode extends along the threading cavity to the slit, and after passing through the slit, it extends to the outer surface of the balloon close to the surface of the proximal tube segment.

2. The radiofrequency ablation catheter according to claim 1, characterized in that: The radio frequency electrode is bonded and connected to the outer sleeve and the proximal tube section at the gap by means of sealant, so that the gap is blocked.

3. The radiofrequency ablation catheter according to claim 1, characterized in that: The central axis of the inner tube is eccentrically arranged relative to the central axis of the outer tube.

4. The radiofrequency ablation catheter according to claim 3, characterized in that: The cross sections of the inner tube and the outer tube are both circular, and the eccentricity between the inner tube and the outer tube is close to the difference between the inner diameter of the outer tube and the outer diameter of the outer tube.

5. The radiofrequency ablation catheter according to claim 4, characterized in that: The central axis of the inflation cavity is farther away from the central axis of the outer sleeve than the central axis of the guide wire tube penetration cavity.

6. The radiofrequency ablation catheter according to claim 1, characterized in that: The radio frequency electrode at least comprises a flexible metal electrode layer, a lining layer, a first flexible conductor layer, a substrate layer, and a second flexible conductor layer stacked in sequence from the outer surface to the inner surface of the balloon, the lining layer and the substrate layer are flexible insulating material layers, the substrate layer is provided with a conductive through hole, and the distal end of the first flexible conductor layer and the distal end of the second flexible conductor layer are connected through the conductive through hole; The portion of the flexible metal electrode layer located in the proximal wiring area is connected to the RF cable in the threading cavity, and the portions of the first flexible conductor layer and the second flexible conductor layer located in the proximal wiring area are respectively connected to two conductive cables in the threading cavity to form a thermocouple loop.

7. The radiofrequency ablation catheter according to claim 1, characterized in that: A developing portion is also provided on a side of the distal ablation zone facing the balloon.

8. The radiofrequency ablation catheter according to claim 7, characterized in that: The developing portion is a closed ring structure, the developing portion is arranged at the edge of the distal ablation zone and the configuration of the developing portion is adapted to the configuration of the distal ablation zone, or the developing portion is a plurality of developing points, and the plurality of developing points are distributed at intervals along the periphery of the distal ablation zone.

9. The radiofrequency ablation catheter according to claim 7, characterized in that: The developing part is a developing part of a platinum-iridium alloy material, and the mass percentage of platinum in the platinum-iridium alloy material is 90%, and the mass percentage of iridium is 10%; and / or the thickness of the developing part is greater than or equal to 0.03 mm and less than or equal to 0.07 mm.

10. The radiofrequency ablation catheter according to any one of claims 1 to 9, characterized in that: It also includes a developing element, which is arranged on the periphery of the distal portion and located in the inner cavity of the balloon; and / or the total thickness of the radio frequency electrode is less than or equal to 0.2 mm.

11. The radiofrequency ablation catheter according to any one of claims 1 to 9, characterized in that: It also includes a handle, a wire threading tube and a plug. The proximal end of the outer sleeve is connected to one end of the handle, and the other end of the handle is connected to the distal end of the wire threading tube. The plug is arranged at the proximal end of the wire threading tube. The cable extends from the proximal end connected to the plug to the distal end connected to the proximal wiring area, along the tube cavity of the wire threading tube to the handle, and extends into the wire threading cavity after being routed through the internal channel of the handle.

12. The radiofrequency ablation catheter according to claim 11, characterized in that: The handle includes an upper cover, a lower cover and a connecting seat, the upper cover and the lower cover are buckled together to enclose a storage space, a portion of the connecting seat is accommodated in the storage space, the connecting seat has a first port connected to the inner tube, a second port connected to the guide wire tube insertion cavity, and a side port connected to the inflation cavity, the second port and the side port are respectively connected to a Luer connector, the Luer connector connected to the second port is used for the guide wire to pass through, and the Luer connector connected to the side port is used for the introduction of pressurized gas.

13. A radiofrequency ablation system, characterized in that: include: A radiofrequency ablation apparatus and a radiofrequency ablation catheter according to any one of claims 1 to 12.

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