Ablation catheter for human body

Abstract

The invention belongs to the field of medical instrument ablation, and provides an ablation catheter for a human body, which comprises a conveying sheath tube, a traction wire movably arranged in the conveying sheath tube in a penetrating manner, at least one ablation electrode and a control handle, the ablation electrode is of an expandable structure, the control handle comprises a shell, a transmission assembly and a push rod, and the near end of the conveying sheath tube is connected with the shell; wherein the transmission assembly comprises a first movable rack, a gear assembly and a second movable rack, the first movable rack is movably arranged in the shell and meshed with the gear assembly, one end of the first movable rack is connected with one end of the push rod, and the second movable rack is movably arranged in the shell and meshed with the gear assembly; one end of the traction wire is connected with one end, away from the push rod, of the second movable rack, and the gear assembly is arranged, so that the stroke of the second movable rack is larger than that of the first movable rack, the ablation electrode is driven to rapidly expand or contract, the control sensitivity of the ablation electrode is improved, and opening and closing of the ablation electrode are accurately controlled.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical device ablation, and in particular relates to an ablation catheter for human body. Background Art

[0002] The prior art has adopted a variety of energy delivery methods in the treatment of human diseases, including radiofrequency, microwave, high-intensity focused ultrasound (HIFU) and pulsed electric fields (PEF).

[0003] Drug treatment mainly includes inhalation of salbutamol sulfate aerosol and salmeterol fluticasone powder inhalation to dilate the trachea, thereby relieving the symptoms of airway diseases; however, drug treatment can only increase airway oxygen uptake and have a relieving effect, but cannot cure the disease.

[0004] The main surgical treatment methods include bullectomy, lung volume reduction surgery and other surgical operations. The disadvantage is that surgical operations cause great damage to patients and may lead to the failure of some lung functions. The main surgical treatment methods are interventional ablation treatments, such as radiofrequency ablation and pulsed electric field ablation. Radiofrequency ablation uses radiofrequency energy to generate thermal energy at the distal end of the catheter, and ablates the tissue by contacting the lesion. However, this ablation based on heat conduction has certain limitations. Heat contact will destroy most of the tissues and cells in the treatment area and will damage healthy cells. In addition, the airway is close to the heart, and excessive heat energy ablation may cause damage to nearby cardiovascular and nerves. The principle of pulsed electric field ablation is to use extremely short high-voltage pulses to act on the phospholipid bilayer of the cell membrane, forming irreversible electroporation on the cell membrane, thereby causing cell apoptosis and achieving the purpose of ablation.

[0005] Pulsed electric field is a non-thermal energy ablation, which causes less damage to healthy tissues. In addition, pulsed electric field ablation is also selective for cells and tissues. Pulsed electric field ablation has a threshold, and can selectively ablate diseased tissues during the ablation process. It is a safe and effective airway ablation treatment method.

[0006] Existing pulse ablation usually requires a single-handed hand mirror, which places higher requirements on the one-handed controllability of consumables. Existing methods mostly include turning the wheel with one hand, pushing the slider with one hand, pushing or pulling back with both hands, etc. At present, manual control of electrode opening and recovery is often used, which cannot be used quickly and efficiently with other new devices (such as robots, etc.). When using a robot to operate the dashboard, it is still necessary to operate the consumables to open and recover. For some surgeries, such as bronchial rheology, the release and recovery actions of consumables are repeated up to 170 times for each operation. The dashboard and consumables increase the duration and complexity of the operation and are prone to operational errors. The use of two people operating at the same time increases personnel costs and may cause damage to the patient's body due to failure to recover during movement. Summary of the invention

[0007] The present invention provides an ablation catheter for human beings, which solves the technical problems existing in the above technical background and facilitates the operation of ablation surgery by surgical personnel.

[0008] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0009] An ablation catheter for a human body, comprising:

[0010] The delivery sheath tube has guiding properties and is provided with a first through passage;

[0011] A traction wire is movably arranged in the first channel of the delivery sheath tube, and the traction wire can move axially relative to the delivery sheath tube;

[0012] At least one ablation electrode is an expandable structure, the ablation electrode can be configured with ablation energy, the ablation electrode is disposed at the distal end of the delivery sheath, the ablation electrode has a first end and a second end, the first end of the ablation electrode is connected to one end of the traction wire, and the second end of the ablation electrode is connected to the distal end of the delivery sheath;

[0013] A control handle, comprising a housing, a transmission assembly and a push rod, wherein the transmission assembly is disposed in the housing, one end of the push rod passes through the housing and is connected to the transmission assembly, the push rod can move back and forth linearly relative to the housing, the other end of the traction wire is connected to the transmission assembly, and the proximal end of the conveyor is connected to the housing;

[0014] The transmission assembly includes a first movable rack, a gear assembly and a second movable rack. The first movable rack is movably disposed in the housing and meshed with the gear assembly. One end of the first movable rack is connected to one end of the push rod. The second movable rack is movably disposed in the housing and meshed with the gear assembly. The second movable rack and the first movable rack move in opposite directions. One end of the traction wire is connected to an end of the second movable rack away from the push rod. The gear assembly is arranged so that the stroke of the second movable rack is greater than the stroke of the first movable rack.

[0015] In some embodiments, the gear assembly includes a first driving gear, a second driven large gear and a second driven small gear, wherein the first driving gear is rotatably disposed in a housing and meshes with the first driven rack, the second driven large gear and the second driven small gear are coaxially fixedly connected and rotatably disposed in the housing, the second driven small gear meshes with the first driving gear, and the second driven large gear meshes with the second driven rack, wherein the outer diameter of the second driven small gear is smaller than the outer diameter of the second driven large gear, and the outer diameter of the first driving gear is larger than the outer diameter of the second driven small gear.

[0016] In some embodiments, a ratio of an outer diameter of the second driven large gear to an outer diameter of the second driven small gear ranges from 1:1.1 to 1:5.

[0017] In some embodiments, a first movable rack is provided on the shell and a first limiting structure is provided between the shell, so that the first movable rack can make reciprocating linear movements, and the first limiting structure includes a first limiting groove provided on the shell and a first limiting boss provided on the first movable rack, or a first limiting boss provided on the shell and a first limiting groove provided on the first movable rack, and the first limiting boss is movably engaged in the first limiting groove.

[0018] In some embodiments, the shell is provided with a first through hole, the shell is provided with a first bracket, the first bracket is provided with a first supporting hole, the first through hole, the first supporting hole and the push rod are coaxially arranged, and one end of the push rod passes through the first through hole and the first supporting hole and is connected to the first moving rack.

[0019] In some embodiments, a first limiting block is provided on a side of the push rod close to the first through hole, and an outer diameter of the first limiting block is larger than an inner diameter of the first through hole.

[0020] In some embodiments, a return spring is provided between the first limit block and the first bracket, one end of the return spring abuts against the first bracket, and the other end of the return spring abuts against the first limit block. In the initial state, the return spring is in a natural state or a compressed state.

[0021] In some embodiments, a second limiting structure is provided between the shell and the second moving rack, and the second limiting structure is used for the second moving rack to make reciprocating linear movement. The second limiting structure includes a second limiting groove provided on the shell and a second limiting boss provided on the second moving rack, or a second limiting boss provided on the shell and a second limiting groove provided on the second moving rack, and the second limiting boss is movably engaged with the second limiting groove.

[0022] In some embodiments, the first limiting structure is arranged on the side of the first moving rack away from the second moving rack, the second limiting structure is arranged on the side of the second moving rack away from the first moving rack, the side of the first moving rack abuts against a side of the first limiting groove, and the second moving rack abuts against a side of the second limiting groove.

[0023] In some embodiments, the first movable rack is provided with a first abutting surface, and the second movable rack is provided with a second abutting surface, and the first abutting surface and the second abutting surface abut against each other.

[0024] In some embodiments, a first limiting plate is provided in the housing, and upper end surfaces of the first movable rack and the second movable rack are both in contact with the first limiting plate.

[0025] In some embodiments, a locking mechanism is further included, wherein the locking mechanism is used to maintain the current expansion state of the ablation electrode.

[0026] In some embodiments, the locking mechanism includes a locking pawl, a locking pawl and a tension spring, the locking pawl is rotatably arranged on the shell, one end of the locking pawl passes through the shell and abuts against the locking pawl, one end of the tension spring is connected to the locking pawl, and the other end is connected to the shell. In an initial state, the locking pawl abuts against a tooth groove of the transmission assembly so that the push rod can only move to one side of the control handle. When the push rod is pushed, the locking pawl can move to the next adjacent tooth groove and abut against it under the action of the tension spring.

[0027] In some embodiments, a locking limit block is provided on the locking pawl, and in an initial state, the locking limit block abuts against the inner wall of the shell.

[0028] In some embodiments, when the number of the ablation electrodes is greater than or equal to two, a first connector is provided between two adjacent ablation electrodes for connection, and the first connector is movably mounted on the traction wire.

[0029] In some embodiments, the first connector and two ablation electrodes connected to two ends of the first connector are integrally constructed, and the first connector is made of a conductive material so that the multiple ablation electrodes are a monopolar ablation structure.

[0030] In some embodiments, the first connecting member is made of insulating material, and any two of the multiple ablation electrodes can be connected to the positive wire and the negative wire respectively to form a bipolar ablation structure, or at least one of the multiple ablation electrodes can be electrically connected to the positive wire to form a monopolar ablation structure.

[0031] In some embodiments, a scale mark is provided on a side of the delivery sheath tube close to the ablation electrode, and the scale mark is evenly distributed from the distal end to the proximal end of the delivery sheath tube.

[0032] In some embodiments, the ablation electrode is a basket weave structure.

[0033] In some embodiments, when the initial outer diameter range of the ablation electrode is 0.1-2 mm, the outer diameter of the ablation electrode can be expanded to or 2.1-60 mm; when the initial outer diameter of the ablation electrode is 0.1-3.2 mm, the outer diameter of the ablation electrode can be expanded to 3.3-60 mm; when the initial outer diameter of the ablation electrode is 0.1-4.2 mm, the outer diameter of the ablation electrode can be expanded to 4.3-60 mm.

[0034] In some embodiments, a guide tip is provided at one end of the traction wire close to the ablation electrode, one end of the ablation electrode is fixed to the guide tip, wherein a smooth guide structure is provided at one end of the guide tip away from the ablation electrode.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The present application changes the moving directions of the first moving rack and the second moving rack by setting a gear assembly inside the control handle, which meshes with the first moving rack and the second moving rack respectively, and at the same time sets the reduction ratio through the gear assembly, so that when the push rod drives the first moving rack to move, the second moving rack can move at a faster speed after being transmitted by the gear assembly, thereby driving the traction wire to move quickly, and then driving the ablation electrode to expand or contract quickly, with sensitive control and fast response speed, which is convenient for operation and adjustment during the operation.

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

[0038] Figure 1 A stereoscopic diagram of an ablation catheter for use in a human body according to the present invention;

[0039] Figure 2 It is a schematic diagram of an expanded state of an ablation electrode of an ablation catheter for a human body according to the present invention;

[0040] Figure 3 It is a schematic diagram of the internal structure of a control handle of an ablation catheter for human body of the present invention;

[0041] Figure 4 It is a first stereoscopic view of a transmission assembly of an ablation catheter for a human body according to the present invention;

[0042] Figure 5 A second stereoscopic view of a transmission assembly of an ablation catheter for a human body according to the present invention;

[0043] Figure 6It is a schematic structural diagram of a shell of an ablation catheter for human body of the present invention;

[0044] Figure 7 It is a schematic structural diagram of another shell of an ablation catheter for human body of the present invention;

[0045] Figure 8 It is a front view of the internal structure of a control handle of an ablation catheter for human body of the present invention;

[0046] Fig. 9 for Figure 8 A magnified image of ;

[0047] Fig.10 It is a schematic diagram of the structure of the present invention applied to an endoscope;

[0048] Fig.11 It is a schematic structural diagram of a plurality of ablation electrodes of an ablation catheter for human body according to the present invention;

[0049] Fig.12 The diagram is a schematic diagram of scale markings on the distal end of a delivery sheath tube of an ablation catheter for human body according to the present invention. DETAILED DESCRIPTION

[0050] The present application is further described in detail below in conjunction with specific drawings. In the description of this embodiment, unless otherwise specified, the terms "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the present application must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present application.

[0051] like Figure 1-2 As shown, an ablation catheter for human body provided by the present invention mainly includes a delivery sheath 200 , a traction wire 300 , an ablation electrode 201 and a control handle 100 .

[0052] The delivery sheath 200 is provided with a first through channel, and has certain guiding properties and flexibility to adapt to various bends of the human body. Specifically, in the present embodiment, the delivery sheath 200 is composed of a multi-layer composite material, and the outer layer is composed of a polymer material with good biocompatibility and has multiple hardness levels. The proximal end near the control handle 100 has good pushing properties and high hardness, and may be PA6, PA12, segmented polyamide or other polymer materials, and the distal end near the ablation electrode 201 has flexibility and low hardness, and may be segmented polyamide, polyamide or other polymer materials.

[0053] The middle layer is composed of a metal wire reinforcement layer, which can be a braided layer, a coil layer or a combination thereof. Furthermore, the braided layer has different braiding densities, and a low-density braiding is used near the proximal end of the control handle 100 to enhance the push, and a high-density braiding is used near the distal end of the ablation electrode 201 to enhance the flexibility. The material of the middle layer can be sus304, sus316 or Ni-Ti, etc.

[0054] Furthermore, the inner layer is composed of a polymer material with good lubricity and low friction resistance to reduce the resistance of the traction wire when it moves in the first channel of the delivery sheath 200. Optionally, the inner layer material can be HDPE, PTFE, FEP or other polymer materials with low friction coefficient.

[0055] Furthermore, an insulating layer is provided on the delivery sheath 200. By providing the insulating layer, when the ablation energy is transmitted from the power connector to the ablation electrode 201, the delivery sheath 200 can prevent current leakage and ablation energy loss. The ablation energy is only released at the ablation electrode, avoiding ablation energy loss and achieving the purpose of precise ablation.

[0056] The traction wire 300 is movably arranged in the first channel of the delivery sheath tube 200, and the traction wire 300 can move axially relative to the delivery sheath tube 200;

[0057] The ablation electrode 201 is arranged at the distal end of the delivery sheath 200. The ablation electrode 201 is an expandable structure, which is adaptively matched and fitted with the human body. In this embodiment, the human body includes but is not limited to the airway, intestines, blood vessels or heart, etc. The ablation electrode 201 can be configured with ablation energy. In this embodiment, the distal end of the delivery sheath 200 is the end away from the control handle 100. The ablation electrode 201 is provided with a first end and a second end. The first end of the ablation electrode 201 is connected to one end of the traction wire 300, and the second end of the ablation electrode 201 is connected to the distal end of the delivery sheath 200. The traction wire 300 drives the first end of the ablation electrode 201 close to the second end, thereby realizing the expansion of the ablation electrode 201, so that the ablation electrode 201 is close to the diseased part of the human body;

[0058] The control handle 100 includes a housing, a transmission assembly and a push rod 101. The transmission assembly is disposed in the housing. One end of the push rod 101 passes through the housing and is connected to the transmission assembly. The push rod 101 can move back and forth linearly relative to the housing. The other end of the traction wire 300 is connected to the transmission assembly. The proximal end of the delivery sheath 200 is connected to the housing.

[0059] Specific as Figure 3-5As shown, the transmission assembly includes a first movable rack 103, a gear assembly and a second movable rack 107. The first movable rack 103 is movably arranged in the shell and meshed with the gear assembly. One end of the first movable rack 103 is connected to one end of the push rod 101. The second movable rack 107 is movably arranged in the shell and meshed with the gear assembly. The moving directions of the first movable rack and the second movable rack are opposite. One end of the traction wire 300 is connected to one end of the second movable rack 107 away from the push rod 101. The gear assembly is set so that the stroke of the second movable rack 107 is greater than the stroke of the first movable rack 103.

[0060] In the present application, by setting a gear assembly, the output speed of the second moving rack is changed, and the output speed of the first moving rack 103 is increased by the gear assembly, so that when the second moving rack 107 moves, it moves at a speed greater than the first moving rack 103, so as to achieve rapid movement of the traction wire 300, so that the first end and the second end of the ablation electrode 201 are quickly brought together or apart, and are rapidly expanded or contracted, thereby improving the control sensitivity of the ablation electrode 201 by the surgeon. At the same time, it is prevented that the ablation electrode is not contracted in time, causing damage to the human body.

[0061] In one embodiment, as described above, when the push rod 102 drives the first movable rack 103 to move, the movement stroke of the second movable rack 107 is greater than the movement stroke of the first movable rack 103 through the transmission of the gear assembly.

[0062] Further, the gear assembly includes a first driving gear 104, a second driven large gear 106 and a second driven small gear 105, wherein the first driving gear 104 is rotatably arranged in the housing through a hole shaft structure, and the first driving gear 104 is meshed with the first driven rack 103, the second driven large gear 106 and the second driven small gear 105 are coaxially arranged, and the two are fixedly connected so as to rotate synchronously, the second driven large gear 106 and the second driven small gear 105 are rotatably arranged in the housing through a hole shaft, the second driven small gear 105 is meshed with the first driving gear 104, and the second driven large gear 106 is meshed with the second driven rack 107, wherein the outer diameter of the second driven small gear 105 is smaller than the outer diameter of the second driven large gear 106, and the outer diameter of the first driving gear 104 is larger than the outer diameter of the second driven small gear 105.

[0063] Specifically, since the second driven large gear 106 and the second driven small gear 105 are coaxial and relatively fixed, they have the same angular velocity, so the second driven large gear 106 with a larger outer diameter has a larger linear velocity. At the same time, since the first driven rack 103 is meshed with the first driving gear 104, and the first driving gear 104 is meshed with the second driven small gear 105, the first driving gear 104 and the second driven small gear 105 have the same linear velocity. When the first driving gear 104 rotates one circle, the second driven small gear 105 can rotate more than one circle, so that the second driven rack 107 can move at a faster speed than the first driven rack 103.

[0064] Optionally, the first driving gear 104 and the second driven pinion gear 105 can be coaxially arranged and fixedly connected. In this case, the outer diameter of the first driving gear 104 is smaller than the outer diameter of the second driven pinion gear 105, and the outer diameter of the second driven large gear 106 is smaller than or equal to the outer diameter of the second driven pinion gear 105. The second driven large gear 106 meshes with the second driven pinion gear 105 and the second driven rack 107 respectively, which can also achieve the above-mentioned speed increase effect.

[0065] Further, the ratio of the outer diameter of the second driven large gear 106 to the outer diameter of the second driven small gear 105 is in the range of 1:1.1 to 1:5.

[0066] In one embodiment, Figure 4 and Figure 7 As shown, a first limiting structure is provided between the first movable rack 103 and the shell body, so that the first movable rack 103 can make reciprocating linear movements. Specifically, the first limiting structure includes a first limiting groove 1014 provided on the shell body and a first limiting boss 1031 provided on the first movable rack 103. In this embodiment, the first limiting groove 1014 is composed of two baffles, which are horizontally arranged and consistent with the moving direction of the push rod 101. The two baffles are arranged at a certain interval with the first line of the stroke as the groove 1014. The thickness of the first limiting boss 1031 matches the interval between the two baffles, so that the first limiting boss 1031 on the first movable rack 103 is clamped in the first limiting groove 1014.

[0067] Optionally, the first limiting boss 1031 may be disposed on the housing, and the first limiting groove 1014 may be disposed on the first movable rack 103 , which can also achieve the above-mentioned effect.

[0068] In one embodiment, in order to make the push rod 101 move linearly, Figure 6As shown, a first through hole 1012 is provided on the housing, a first bracket 108 is provided in the housing, a first supporting hole 1081 is provided on the first bracket 108, the first through hole 1012, the first supporting hole 1081 and the push rod 101 are coaxially arranged, and the shape of the push rod 101 is adapted to the size of the first supporting hole 1081 and the first through hole 1012. One end of the push rod 101 passes through the first through hole 1012 and the first supporting hole 1081 and is connected to the first movable rack 103.

[0069] Furthermore, in order to prevent the push rod 101 from detaching from the shell, a first limit block 1011 is set on the push rod 101. The first limit block 1011 is located inside the shell and is set close to the first through hole 1012. The outer diameter profile of the first limit block 1011 is larger than the inner diameter of the first through hole 1012. When in the extreme position, the first limit block 1011 contacts the inner wall of the shell.

[0070] Furthermore, in order to make the push rod 101 reset itself, a reset spring 102 is arranged between the first limit block 1011 and the first bracket 108, one end of the reset spring 102 is connected to the first limit block 1011, and the reset spring 102 is sleeved on the push rod 101 and the other end is connected to the first bracket 108. In the initial state, the reset spring 1011 is in a natural state or a compressed state. When the push rod 101 moves, the first limit block 1011 is driven to squeeze the reset spring 102, and the reset spring 102 is compressed. When the push rod 101 is released, it is not controlled by external force and resets under the elastic force of the reset spring 102.

[0071] Optionally, the return spring 102 may also be replaced by an elastic structural member such as a spring sheet.

[0072] In one embodiment, Figure 5 and Figure 6 As shown, in order to ensure that the second movable rack 107 makes reciprocating linear movement, a second limiting structure is provided between the shell and the second movable rack 107, and the second limiting structure includes a second limiting groove 1013 arranged on the shell and a second limiting boss 1071 arranged on the second movable rack 107, the second limiting boss 1071 is adapted to the second limiting groove 1013, and the second limiting boss 1071 is movably engaged in the second limiting groove 1013. Specifically, in this embodiment, the second limiting groove 1013 is composed of two baffles, and its structural principle is the same as that of the first limiting groove 1014, and no further details are given here.

[0073] Optionally, the second limiting boss 1071 may be disposed on the housing, and the second limiting groove 1013 may be disposed on the second movable rack 107 , which can also achieve the above-mentioned effect.

[0074] In one embodiment, Figure 5 and Figure 6As shown, the first limiting structure is arranged on the side of the first movable rack 103 away from the second movable rack 107, the second limiting structure is arranged on the side of the second movable rack 107 away from the first movable rack 103, the side of the first movable rack 103 abuts against one side of the first limiting groove 104, and the second movable rack 107 abuts against one side of the second limiting groove 1013. That is, the first limiting structure and the second limiting structure are arranged on two opposite sides of the housing, so that the movement of the first movable rack 103 and the second movable rack 107 is not interfered.

[0075] In one embodiment, in order to make the housing structure compact and the first movable rack 103 and the second movable rack 107 only move back and forth in a straight line, a first abutting surface 1032 is provided on the first movable rack 103, and a second abutting surface 1072 is provided on the second movable rack 107, wherein the first abutting surface 1032 and the second abutting surface 1072 abut against each other, and at the same time, the side surface of the first movable rack 103 abuts against the first limiting groove 1014, and the side surface of the second movable rack 107 abuts against the second limiting groove 1013, thereby limiting the first movable rack 103 and the second movable rack 107. In this embodiment, the first abutting surface 1032 and the second abutting surface 1072 are both planar structures. Optionally, the first abutting surface 1032 and the second abutting surface 1072 may also be tangent structures, that is, the first abutting surface 1032 is a curved surface structure, and the second abutting surface 1072 is a planar structure, or the two structures are opposite, or the first abutting surface 1032 and the second abutting surface 1072 are both curved surface structures.

[0076] In one embodiment, Figure 3 and Figure 8 As shown, in order to prevent the first movable rack 103 and the second movable rack 107 from swinging up and down, a first limit plate 109 is provided on the housing, wherein the upper end surface of the first movable rack 103 and the upper end surface of the second movable rack 107 are both in contact with the first limit plate 109. In the present application, the contact surfaces of the first limit plate 109 and the first movable rack 103 and the second movable rack 107 are both planes.

[0077] In one embodiment, Figure 8 and Fig. 9 As shown, a locking mechanism 400 is also included, and the locking mechanism 400 is used to maintain the current expansion state of the ablation electrode 201.

[0078] Specifically, the locking mechanism 400 includes a locking pawl 402, a locking pawl 401 and a tension spring 403. The locking pawl 102 is rotatably arranged on the shell. One end of the locking pawl 401 passes through the shell and abuts against the locking pawl 402. One end of the tension spring 403 is connected to the locking pawl 402, and the other end is connected to the shell. In the initial state, the locking pawl 402 abuts against a tooth groove of the transmission assembly. When the push rod 101 is pushed, the locking pawl 402 can move to the next adjacent tooth groove under the action of the tension spring 403.

[0079] In this embodiment, the locking pawl 402 is movably engaged with the tooth groove of the first driving gear 104. Fig. 9 As shown, since the locking pawl 401 abuts against the locking pawl 402 to limit the position, the first driving gear 104 cannot rotate toward the side close to the locking pawl 401. Figure 8 When the push rod 101 drives the first movable rack 103 to move, the first driving gear 104 rotates clockwise, and the first driving gear 104 drives the locking pawl 402 to rotate toward the side away from the locking pawl 401, and at the same time stretches the tension spring 403. When the locking pawl 402 disengages from the current tooth groove, the locking pawl 402 is reset under the action of the tension spring 403, so as to be engaged with the next tooth groove of the first driving gear 104 for locking.

[0080] Optionally, the tension spring 403 may also be arranged on the other side of the locking pawl 402 , that is, when the first driving gear 104 drives the locking pawl 402 to rotate, the locking pawl 402 compresses the tension spring 403 .

[0081] Furthermore, a locking limit block 4011 is provided on the locking pawl 401. In the initial state, the locking limit block 4011 abuts against the inner wall of the shell to prevent the locking pawl 401 from withdrawing from the shell, and at the same time supports the locking pawl 402 so that the locking pawl 402 is fixed in the same appropriate position, that is, a part of the locking pawl 402 can be engaged in the tooth groove of the first driving gear 104.

[0082] Optionally, the locking mechanism 400 may also lock the first movable rack 103 or the second movable rack 107 . The specific installation position is not limited by the present invention. The purpose is to prevent the ablation electrode 201 from shrinking during the operation.

[0083] In one embodiment, Fig.11As shown, in order to make the ablation range larger, a plurality of expandable ablation electrodes 201 are arranged at the distal end of the delivery sheath 200, when the number of ablation electrodes 201 is greater than 2. A first connecting member 102 is arranged between two adjacent ablation electrodes 201, and the first connecting member 102 is movably sleeved on the traction wire 300, and the two ends of the two adjacent ablation electrodes 201 are respectively connected to the two ends of the first connecting member 102. In this embodiment, the first connecting member 102 is set to a certain length, so that a certain distance is set between the two adjacent ablation electrodes 201.

[0084] Furthermore, the first connector 102 and the two ablation electrodes 201 connected to the two ends of the first connector 102 are integrally constructed. The first connector 102 is made of conductive material. When the electrode wire 204 is connected to one of the ablation electrodes 201, multiple ablation electrodes 201 can be energized to form a monopolar ablation structure, thereby increasing the ablation range to accommodate ablation of larger lesions.

[0085] Furthermore, the first connector 102 can be made of insulating material. To expand the ablation range, any two of the multiple ablation electrodes 201 can be connected to the positive wire and the negative wire respectively. The positive wire and the negative wire are connected to the external energy generator, so that a dual-electrode ablation structure is formed between the two ablation electrodes 201 connected to the positive wire and the negative wire. Since the current of the bipolar structure passes through the medium stably, the current density is stable, so that the output energy efficiency of the bipolar state is more stable. Optionally, when the number of ablation electrodes 201 is greater than three, by energizing any two of the ablation electrodes 201, the distance between the two energized ablation electrodes 201 is adjusted, thereby adjusting the ablation range to meet the needs of lesion ablation.

[0086] Optionally, when multiple ablation electrodes 201 are connected to corresponding positive wires, the positive wires are connected to an external energy generator, and the negative electrode of the energy generator is fixed to the human body surface through a back plate, thereby achieving ablation of a single ablation electrode 201 and reducing the ablation range to adapt to ablation of smaller ablation lesions.

[0087] Furthermore, when there are multiple ablation electrodes 201, the ablation electrodes 201 are of different sizes. The ablation electrode 201 far from the distal end of the delivery sheath 200 has a small expansion range, while the ablation electrode 202 near the distal end of the delivery sheath 200 has a large expansion range, which has been adapted to the needs of different lesions.

[0088] In one embodiment, Fig.10 and Fig.12As shown, in order to facilitate the surgeon to confirm the position of the ablation catheter, an endoscope 500 is required for auxiliary operation. The lesion point is found through the endoscope 500, and then the ablation catheter enters the lesion through the working channel of the endoscope 500. The surgeon operates the control handle 100 to expand the ablation electrode 201 to abut against the inner wall of the human lesion, and maintains the expanded state after abutment, and then performs energy delivery and ablation. Furthermore, since the ablation catheter needs to be used under the working channel of the endoscope 500, a scale mark 205 is set at the distal end of the delivery sheath 200, and the scale mark 205 is evenly distributed from the distal end to the proximal end of the delivery sheath 200. When the ablation catheter extends out of the working forceps channel, the scale mark 205 will be exposed under the lens of the endoscope 500, and the surgeon can observe the scale mark 205 through the lens to determine the position of the ablation electrode 201, so that the ablation electrode 201 can accurately reach the lesion position and increase the success rate of the operation.

[0089] In one embodiment, the ablation electrode 201 is a basket weaving structure. Specifically, the ablation electrode 201 is prepared by weaving metal wires, and the ablation electrode 201 in this manner can be opened and closed in size, and has the characteristics of low resistance and low external tension, and can fully fit the lesion site while causing little damage to the airway, and can achieve good treatment effects after releasing the pulsed electric field.

[0090] Furthermore, the braided wire of the ablation electrode 201 is made of a metal material with low resistance, good elasticity and not prone to plastic deformation, which may be SUS304, SUS316L, cobalt-chromium alloy, nickel-titanium alloy, etc.;

[0091] Furthermore, the ablation electrode 201 with a basket weaving structure can be in a teardrop shape, a spindle shape, a blade shape, etc. after expansion. This type of shape has a large outer diameter in the middle area and a small outer diameter at both end areas. The supporting force at both end areas is strong, and the supporting force in the middle area is weak. The strong supporting force on both sides can ensure that the ablation electrode is straight, and the supporting force in the middle area is weak, which has good compliance and can ensure a good wall-adhering effect.

[0092] Furthermore, the basket weaving structure of the ablation electrode 201 can be woven in a manner of 1-on-1, 1-on-2, 2-on-2 or other weaving manners. This weaving manner can make the ablation electrode 201 uniform and circularly open and close, and can fully cover the diseased airway to obtain a good treatment effect.

[0093] Furthermore, the weaving density PPI of the ablation electrode 201 with a basket weaving structure can be 5 to 60. This weaving density can provide good radial support when opened, can fit tightly with the airway, and obtain good treatment effects. At the same time, this weaving density has a smaller outer diameter when closed, and can pass through the working channel of the endoscope to easily reach the lesion site.

[0094] Furthermore, the ablation electrode 201 is polished to have a smaller high-frequency resistance, thereby improving the transmission capability of the pulse electric field and promoting the electroporation effect of cells.

[0095] Furthermore, electrode rings 202 are provided at both ends of the ablation electrode 201 with the basket weaving structure. The electrode rings 202 wrap the both ends of the ablation electrode 201 with the basket weaving structure to limit the longitudinal length of the ablation electrode 201 .

[0096] Furthermore, the electrode wire is connected to the electrode ring 202 for electrical conduction, thereby avoiding the occurrence of virtual connection and missing connection, thereby improving the stability of electrical conduction.

[0097] Furthermore, when the initial outer diameter range of the ablation electrode 201 is 0.1-2 mm, under the traction of the traction wire 300, the outer diameter of the ablation electrode 201 can be expanded to or 2.1-60 mm. For example, the outer diameter of the ablation electrode 201 in the initial state can be 0.4 mm, 0.6 mm, 1.0 mm or 1.5 mm, etc.; in the expanded state, the outer diameter of the ablation electrode 201 can be 3 mm, 5 mm, 20 mm or 50 mm, etc.

[0098] When the initial outer diameter of the ablation electrode 201 is 0.1-3.2 mm, the outer diameter of the ablation electrode 201 can be expanded to 3.3-60 mm. For example, in the initial state, the outer diameter of the ablation electrode 201 can be 0.3 mm, 3.0 mm, 1.2 mm or 1.8 mm, and in the expanded state, the outer diameter of the ablation electrode 201 can be expanded to different diameters such as 3.4 mm, 3.9 mm, 35 mm or 50 mm.

[0099] When the initial outer diameter of the ablation electrode 201 is 0.1-4.2 mm, the outer diameter of the ablation electrode 201 can be expanded to 4.3-60 mm. For example, the outer diameter of the ablation electrode 201 in the initial state can be 0.1 mm, 1.0 mm, 1.8 mm or 4.2 mm, and the outer diameter of the ablation electrode 201 after expansion can be different diameters such as 4.3 mm, 10 mm, 25 mm or 60 mm.

[0100] By setting the outer diameters of the ablation electrodes 201 in the initial state and the outer diameters in the expanded state, the sizes of the working channels of different endoscopes 500 can be matched, so that surgeons can flexibly apply them to suit lesions of various sizes in the human body, thereby increasing the scope of ablation treatment.

[0101] In one embodiment, a guide tip 301 is provided at one end of the traction wire 300 close to the ablation electrode 201, and one end of the ablation electrode 201 is fixed to the guide tip 301, wherein a smooth guide structure is provided at one end of the guide tip 301 away from the ablation electrode 201, and the smooth guide structure is a spherical surface or an arc surface. Specifically, the guide tip 301 and the ablation electrode 201 can be connected by hot melt, glue bonding, laser welding, etc. The guide tip 301 has a soft feature, which can effectively reduce damage to the human body part during the process of introduction into the airway or other parts of the human body. Furthermore, the guide tip 301 is a polymer material, which can be composed of block polyetheramide resin, polyurethane rubber, silicone, etc. By providing a smooth guide structure, the damage to the lesion wall can be effectively reduced during the process of introduction into the human body.

[0102] The above is only a preferred embodiment of the present invention. It should be noted that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications should also be considered as the protection scope of the present invention.

Claims

1. An ablation catheter for human body, characterized in that: include: The delivery sheath tube has guiding properties and is provided with a first through passage; A traction wire is movably arranged in the first channel of the delivery sheath tube, and the traction wire can move axially relative to the delivery sheath tube; At least one ablation electrode is an expandable structure, the ablation electrode can be configured with ablation energy, the ablation electrode is disposed at the distal end of the delivery sheath, the ablation electrode has a first end and a second end, the first end of the ablation electrode is connected to one end of the traction wire, and the second end of the ablation electrode is connected to the distal end of the delivery sheath; A control handle, comprising a housing, a transmission assembly and a push rod, wherein the transmission assembly is disposed in the housing, one end of the push rod passes through the housing and is connected to the transmission assembly, the push rod can move back and forth linearly relative to the housing, the other end of the traction wire is connected to the transmission assembly, and the proximal end of the conveyor is connected to the housing; The transmission assembly includes a first movable rack, a gear assembly and a second movable rack. The first movable rack is movably disposed in the housing and meshed with the gear assembly. One end of the first movable rack is connected to one end of the push rod. The second movable rack is movably disposed in the housing and meshed with the gear assembly. The second movable rack and the first movable rack move in opposite directions. One end of the traction wire is connected to an end of the second movable rack away from the push rod. The gear assembly is arranged so that the stroke of the second movable rack is greater than the stroke of the first movable rack.

2. The ablation catheter for human body according to claim 1, characterized in that: The gear assembly includes a first driving gear, a second driven large gear and a second driven small gear, wherein the first driving gear is rotatably disposed in the housing and meshes with the first driven rack, the second driven large gear and the second driven small gear are coaxially fixedly connected and rotatably disposed in the housing, the second driven small gear meshes with the first driving gear, and the second driven large gear meshes with the second driven rack, wherein the outer diameter of the second driven small gear is smaller than the outer diameter of the second driven large gear, and the outer diameter of the first driving gear is larger than the outer diameter of the second driven small gear.

3. The ablation catheter for human body according to claim 2, characterized in that: The ratio of the outer diameter of the second driven large gear to the outer diameter of the second driven small gear is in a range of 1:1.1 to 1:

5.

4. The ablation catheter for human body according to claim 1, characterized in that: A first movable rack is provided on the shell and a first limiting structure is provided between the shell, so that the first movable rack can move back and forth in a straight line. The first limiting structure includes a first limiting groove provided on the shell and a first limiting boss provided on the first movable rack, or a first limiting boss provided on the shell and a first limiting groove provided on the first movable rack, and the first limiting boss is movably engaged in the first limiting groove.

5. The ablation catheter for human body according to claim 1, characterized in that: The shell is provided with a first through hole, the shell is provided with a first bracket, the first bracket is provided with a first supporting hole, the first through hole, the first supporting hole and the push rod are coaxially arranged, and one end of the push rod passes through the first through hole and the first supporting hole and is connected to the first moving rack.

6. The ablation catheter for human body according to claim 5, characterized in that: A first limiting block is provided on one side of the push rod close to the first through hole, and the outer diameter of the first limiting block is larger than the inner diameter of the first through hole.

7. The ablation catheter for human body according to claim 6, characterized in that: A return spring is provided between the first limit block and the first bracket, one end of the return spring abuts against the first bracket, and the other end of the return spring abuts against the first limit block. In the initial state, the return spring is in a natural state or a compressed state.

8. The ablation catheter for human body according to claim 4, characterized in that: A second limiting structure is provided between the shell and the second moving rack, and the second limiting structure is used for the second moving rack to make reciprocating linear movement. The second limiting structure includes a second limiting groove arranged on the shell and a second limiting boss arranged on the second moving rack, or a second limiting boss arranged on the shell and a second limiting groove arranged on the second moving rack, and the second limiting boss is movably engaged with the second limiting groove.

9. The ablation catheter for human body according to claim 8, characterized in that: The first limiting structure is arranged on the side of the first moving rack away from the second moving rack, the second limiting structure is arranged on the side of the second moving rack away from the first moving rack, the side of the first moving rack abuts against a side of the first limiting groove, and the second moving rack abuts against a side of the second limiting groove.

10. The ablation catheter for human body according to claim 9, characterized in that: The first movable rack is provided with a first abutting surface, and the second movable rack is provided with a second abutting surface, and the first abutting surface and the second abutting surface abut against each other.

11. The ablation catheter for human body according to claim 9, characterized in that: A first limiting plate is disposed in the housing, and upper end surfaces of the first movable rack and the second movable rack are both in contact with the first limiting plate.

12. The ablation catheter for human body according to claim 2, characterized in that: Also included is a locking mechanism, which is used to maintain the current expansion state of the ablation electrode.

13. The ablation catheter for human body according to claim 12, characterized in that: The locking mechanism includes a locking pawl, a locking pawl and a tension spring. The locking pawl is rotatably arranged on the housing. One end of the locking pawl passes through the housing and abuts against the locking pawl. One end of the tension spring is connected to the locking pawl, and the other end is connected to the housing. In an initial state, the locking pawl abuts against a tooth groove of the transmission assembly so that the push rod can only move toward one side of the control handle. When the push rod is pushed, the locking pawl can move to the next adjacent tooth groove and abut against it under the action of the tension spring.

14. The ablation catheter for human body according to claim 13, characterized in that: The locking pawl is provided with a locking limit block, and in an initial state, the locking limit block abuts against the inner wall of the housing.

15. The ablation catheter for human body according to claim 1, characterized in that: When the number of the ablation electrodes is greater than or equal to two, a first connector is provided between two adjacent ablation electrodes for connection, and the first connector is movably sleeved on the traction wire.

16. The ablation catheter for human body according to claim 15, characterized in that: The first connecting member and two ablation electrodes connected to two ends of the first connecting member are integrally constructed, and the first connecting member is made of a conductive material so that the multiple ablation electrodes are a monopolar ablation structure.

17. The ablation catheter for human body according to claim 15, characterized in that: The first connecting member is made of insulating material, and any two of the multiple ablation electrodes can be connected to the positive wire and the negative wire respectively, so that the two ablation electrodes form a bipolar ablation structure, or at least one of the multiple ablation electrodes can be electrically connected to the positive wire to form a monopolar ablation structure.

18. The ablation catheter for human body according to claim 1, characterized in that: A scale mark is provided on one side of the delivery sheath tube close to the ablation electrode, and the scale mark is evenly distributed from the distal end to the proximal end of the delivery sheath tube.

19. The ablation catheter for human body according to claim 1, characterized in that: The ablation electrode is a basket weaving structure.

20. The ablation electrode for human body according to claim 19, characterized in that: When the initial outer diameter of the ablation electrode is in the range of 0.1-2mm, the outer diameter of the ablation electrode can be expanded to 2.1-60mm; when the initial outer diameter of the ablation electrode is 0.1-3.2mm, the outer diameter of the ablation electrode can be expanded to 3.3-60mm; when the initial outer diameter of the ablation electrode is 0.1-4.2mm, the outer diameter of the ablation electrode can be expanded to 4.3-60mm.

21. The ablation catheter for human body according to claim 1, characterized in that: A guide tip is arranged at one end of the traction wire close to the ablation electrode, one end of the ablation electrode is fixed to the guide tip, wherein a smooth guide structure is arranged at one end of the guide tip away from the ablation electrode.

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