A cryoablation catheter with controllable ablation zone

Abstract

The application discloses a cryoablation catheter with controllable ablation range, which is capable of adjusting the effective cryoablation length of a balloon by adjusting the position of a displacement block, i.e. the displacement block is relatively movable on the length of the balloon, the balloon at the blocked position cannot be expanded (the expansion of the balloon is limited by the displacement block), the balloon at the unblocked position can be normally expanded (after being filled with refrigerant), and the effective cryoablation length (expandable part) of the balloon can be adjusted, so that the effective ablation range of the cryoablation balloon can be changed.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of cryoablation, in particular to a cryoablation catheter with controllable ablation range. BACKGROUND

[0002] The natural cavity structure of the human body is used for minimally invasive surgery under an endoscope, which has the advantages of small trauma, short operation time and high safety. The current treatment methods include "cold" and "hot" ablation methods. The hot principle treatment method, such as radiofrequency ablation, has been successful in some fields, but radiofrequency ablation has several major drawbacks, including incomplete ablation, lack of visualization during catheter insertion, potential overlap during treatment (some areas receive twice as much energy as other areas), tissue charring, and the need for frequent debridement. Cryoablation treatment refers to a method of freezing diseased tissue by low-temperature technology to achieve in situ inactivation of solid tissue. The principle of action is to use low temperature to rapidly cool the diseased tissue to destroy cells and cause cell necrosis or apoptosis, thereby achieving the treatment purpose. Cryoablation has higher safety, less stimulation and damage to the cavity wall tissue, and is less likely to cause complications such as fistula or stenosis compared to hot ablation. Cryoablation is used under the guidance of an endoscope and is a minimally invasive treatment method that is increasingly used.

[0003] Cryoablation is commonly used in the airway and is increasingly used to treat a variety of indications, such as airway stenosis. Due to the diverse distribution of airway stenosis in the airway, there may be extensive circumferential stenosis or small-range local stenosis. When performing cryoablation in the lung with a cryoballoon, if the ablation range of the cryoballoon is fixed, different models of cryoballoons need to be replaced during treatment according to the situation of different treatment sites to achieve good treatment results while minimizing damage to normal tissue, which brings great inconvenience to clinical operation. Another application scenario in the airway is to damage the pulmonary vagus nerve (pulmonary vagus nerve located outside the airway wall) by interventional cryoablation in the airway, block the conduction of the vagus nerve, and reduce the secretion of acetylcholine. Due to the differences between individuals, the diameter or length of the airway lumen varies (such as irregular shape or short bronchial length). When the ablation range (length, circumference or local adjustment) of the cryoballoon can be adjusted in a timely manner, it can be well adapted to various differences and more targeted cryoablation can be achieved to achieve better treatment results and better safety performance.

[0004] Currently, the cryoballoon used in clinical practice generally has a fixed ablation range and cannot be adjusted in a timely manner during use, which is inconvenient to use. Therefore, a cryoablation technology with a controllable range is needed to achieve better treatment results, simpler clinical operation and safer treatment methods. SUMMARY

[0005] The application aims at providing a cryoablation catheter with controllable ablation range to solve the problems in the prior art.

[0006] To achieve the above object, the application adopts the technical scheme of:

[0007] The application provides a cryoablation catheter with controllable ablation range, which comprises a displacement block, a moving rod, a cryoballoon, a gas return pipeline, a gas inlet pipeline and a handle. The gas return pipeline is used for the return flow of refrigerant, and the distal end thereof is fixedly and sealingly connected to the proximal end of the cryoballoon. The gas inlet pipeline is used for the input of refrigerant, is arranged in the gas return pipeline, and the distal end thereof is arranged in the cryoballoon. The distal end of the displacement block is fixedly connected to the distal end of the moving rod. The moving rod is sealingly and relatively movably connected to the distal end of the cryoballoon. The proximal end of the moving rod is sealingly and relatively movably connected to an adapter on the gas return pipeline. The cryoballoon has a compressed state without refrigerant and an expanded state with refrigerant. When the cryoballoon is in the compressed state, the moving rod is moved towards the proximal end, so that the displacement block is relatively moved on the periphery of the cryoballoon in the compressed state.

[0008] Further, the proximal end of the gas return pipeline is provided with a gas return pipeline connector, and the gas return pipeline connector is fixedly connected to the handle.

[0009] Further, the proximal end of the gas inlet pipeline is provided with a gas inlet pipeline connector, and the gas inlet pipeline connector is fixedly connected to the handle.

[0010] Further, the gas inlet pipeline is provided with a plurality of refrigerant outlet ports on the pipe wall of the cryoballoon part.

[0011] Further, the displacement block is a circular pipe with a sealed distal end.

[0012] Further, the displacement block is a circular pipe with a sealed distal end and a hollowed proximal end, comprising one or more hollowed parts, the hollowed parts are radially arranged and extend to the proximal end of the displacement block, and the width of the hollowed parts is constant.

[0013] Further, the adapter is provided with a fixing tooth, the proximal end of the moving rod is provided with a fixing seat, and the fixing tooth and the fixing seat can be engaged with each other.

[0014] Further, the moving rod is a hollow pipe, the part of the distal end of the moving rod in the cryoballoon is a low-hardness section, a shaping rod is arranged in the cavity of the moving rod, the shaping rod and the moving rod are relatively movable, and the distal end of the shaping rod is provided with a fixed shape part with a predetermined shape, and the predetermined shape has an angle.

[0015] Further, the fixed shape part is made of a shape memory alloy material.

[0016] The present application has the following technical advantages compared with the prior art by adopting the above technical scheme.

[0017] The present application can adjust the effective freezing length of the balloon (the expandable part) by shifting the position of the shifting block, i.e., the shifting block can move relatively on the balloon length, the balloon at the blocked part cannot be expanded (the expansion of the balloon is limited by the shifting block), and the balloon at the unblocked part can be normally expanded (after being filled with refrigerant), thereby realizing the change of the effective ablation range of the cryoballoon.

[0018] The present application can adjust the effective ablation part of the cryoballoon by different setting of the shape of the shifting block, movement or rotation of the moving rod, and adjustment of the position of the shifting block.

[0019] The moving rod of the present application is a pipe material, the hardness of a section of the moving rod in the balloon is reduced, a shaping rod (a distal end with a predetermined shape) is arranged in the lumen of the moving rod, the shaping rod and the moving rod can move relatively, when the fixed shape part of the shaping rod moves to the low-hardness section of the moving rod, the shape of the fixed shape part of the shaping rod can change the shape of the moving rod, thereby changing the shape of the cryoballoon, realizing the bending angle balloon, and adapting to the cryoablation treatment of specific parts of the human body. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a schematic diagram of the cryoablation catheter with controllable ablation range in embodiment 1 of the present application, wherein the cryoballoon is in a short effective freezing length state.

[0021] Figure 2 is a schematic diagram of the cryoablation catheter with controllable ablation range in embodiment 1 of the present application, wherein the cryoballoon is in a long effective freezing length state.

[0022] Figure 3 is a partial schematic diagram of the cryoablation catheter with controllable ablation range in embodiment 1 of the present application.

[0023] Figure 4 is a schematic diagram of the shifting block in embodiment 2 of the present application.

[0024] Figure 5 is a schematic diagram of the cryoablation catheter with controllable ablation range in embodiment 2 of the present application, wherein the cryoballoon is in a short effective freezing length state.

[0025] Figure 6 is a schematic diagram of the shifting block in embodiment 3 of the present application.

[0026] Figure 7 is a cross-sectional view of the cryoballoon in the expanded state in embodiment 3 of the present application.

[0027] Figure 8 is a schematic diagram of the cryoablation catheter with controllable ablation range in embodiment 4 of the present application. DETAILED DESCRIPTION

[0028] The application will be described in detail and specifically below with specific examples and drawings, so that the application can be better understood. However, the following examples do not limit the scope of the application.

[0029] Example 1

[0030] With reference to Figure 1 and Figure 2 , the embodiment discloses a cryoablation catheter with controllable ablation range, which comprises a displacement block 1, a moving rod 2, a cryoballoon 3, a gas return pipeline 4, a gas inlet pipeline 5 and a handle 6. The gas return pipeline 4 is used for the return flow of refrigerant, and the distal end of the gas return pipeline 4 is fixedly and sealingly connected to the proximal end of the cryoballoon 3. The proximal end of the gas return pipeline 4 is provided with a gas return pipeline connector 42, and the gas return pipeline connector 42 is fixedly connected to the handle 6. The gas inlet pipeline 5 is used for the input of refrigerant, and is arranged in the gas return pipeline 4. The distal end of the gas inlet pipeline 5 is arranged in the cryoballoon 3, and the proximal end of the gas inlet pipeline 5 is provided with a gas inlet pipeline connector 52, which is fixedly connected to the handle 6.

[0031] The distal end of the displacement block 1 is fixedly connected to the distal end of the moving rod 2. The moving rod 2 is sealingly and relatively movably connected to the distal end of the cryoballoon 3. The proximal end of the moving rod 2 is sealingly and relatively movably connected to the adapter 41 on the gas return pipeline 4. The cryoballoon 3 has a compressed state without refrigerant and an expanded state with refrigerant. The refrigerant fills the cryoballoon to expand the cryoballoon, and at this time, the length of the cryoballoon is the effective freezing length. When the cryoballoon 3 is in the compressed state, the moving rod 2 is moved to the proximal end, so that the displacement block 1 moves relative to the outer periphery of the cryoballoon 3 in the compressed state. The relative position of the displacement block 1 and the cryoballoon 3 is adjusted, that is, the effective freezing length / ablation range of the cryoballoon 3 in the expanded state is adjusted. Within a certain range, the greater the distance between the distal end of the displacement block 1 and the distal end of the cryoballoon 3, the greater the effective freezing length / ablation range of the cryoballoon 3, and vice versa.

[0032] In the application, the moving rod 2 can be rotated by any angle while moving forward and backward, that is, the angle of the displacement block 1 is adjusted, the position of the expanded part of the cryoballoon 3 is adjusted, the real-time adjustment of the expanded part of the cryoballoon 3 is realized, the use is more convenient during the operation, the operation is easy, and the application range is wider.

[0033] As a preferred example, a plurality of refrigerant discharge ports 51 are arranged on the pipe wall of the cryoballoon 3, which are used for releasing the refrigerant into the cryoballoon 3.

[0034] In the embodiment, the displacement block 1 is a circular tube with a sealed distal end.

[0035] As a preferred example, with reference to Figure 3The adapter 41 is provided with a fixing tooth 411, and the proximal end of the moving rod 2 is provided with a fixing seat 21 which can be fixed with or moved relative to the moving rod 2 (such as being fixed with or moved relative to the moving rod 2 by screwing or unscrewing). After the position of the moving rod 2 is adjusted, the fixing seat 21 is adjusted to a suitable position and fixed, the fixing tooth 411 is engaged with the fixing seat 21, the fixing tooth 411 can prevent the fixing seat 21 from moving, that is, the moving rod 2 and the displacement block 1 are blocked, the position of the displacement block 1 and the shape of the cryoballoon 3 can be better maintained, the control of the cryoballoon ablation range is more accurate, and the cryoballoon ablation catheter is more convenient to use.

[0036] Embodiment 2

[0037] With reference to Figure 4 and Figure 5 , the embodiment discloses a cryoablation catheter with controllable ablation range, which is different from embodiment 1 in that the displacement block 1 is a circular tube with a sealed distal end and a hollowed proximal end, and the displacement block 1 comprises three hollow parts 11 which are radially arranged and extend to the proximal end of the displacement block 1, and the widths of the hollow parts 11 are constant.

[0038] In the embodiment, the hollow part of the displacement block 1 is semicircular, so that the cryoballoon is partially expanded in a semicircular shape, and local treatment in a cavity is achieved. When the lesion in the cavity is a local lesion (non-circumferential lesion), the structure can achieve local treatment of the lesion in the cavity, and normal tissues are protected as much as possible, so that the cryoablation treatment effect is achieved while the damage to non-lesion parts is reduced.

[0039] Embodiment 3

[0040] With reference to Figure 6 and Figure 7 , the embodiment discloses a cryoablation catheter with controllable ablation range, which is different from embodiment 1 in that the displacement block 1 is a circular tube with a sealed distal end and a hollowed proximal end, and the displacement block 1 comprises three hollow parts 11 which are radially arranged and extend to the proximal end of the displacement block 1, and the widths of the hollow parts 11 are constant.

[0041] When the hollow part 11 of the displacement block 1 is three, the cryoballoon 3 is expanded in a three-lobed shape, and only the part of the cryoballoon 3 in contact with human tissues is the effective cryoablation area. When the cryoballoon 3 is cooled in the cavity, the cryoballoon 3 can expand the entire cavity, and only the contact part is the cryoablation area. The expansion of the cavity can make the endoscopic field of view clearer (surgical operation field of view), which is convenient for operation. If the cryoablation catheter is used in the airway, the gap part (non-tissue contact part) can also maintain the ventilation of the lung, so that the patient will not be oxygen-deficient during the operation.

[0042] In addition, the hollow parts 11 can be uniformly or non-uniformly distributed according to the treatment requirements, so as to form different expansion shapes of the cryoballoon.

[0043] Embodiment 4

[0044] Reference Figure 8 The embodiment disclosed in the present application is a cryoablation catheter with controllable ablation range, which is different from Embodiment 1 in that the moving rod 2 is a hollow pipe, the low-hardness section 22 is arranged at the distal end of the moving rod 2 in the cryoballoon 3, and the shaped rod 7 is arranged in the cavity of the moving rod 2, the shaped rod 7 is movable relative to the moving rod 2, and the distal end of the shaped rod 7 is provided with a fixed shape part (for example, a fixed shape of a shape memory alloy material with good elasticity).

[0045] When the fixed shape part of the shaped rod 7 moves to the low-hardness section 22 of the moving rod 2, the shape of the fixed shape part of the shaped rod 7 can change the shape of the moving rod 2, and further change the shape of the cryoballoon 3, so as to realize a bendable cryoballoon with a bending angle, which is suitable for cryoablation treatment of specific parts of the human body, such as the left and right main bronchi of the lung, the fundus or body of the stomach, and the top of the hollow organs (such as the top of the bladder), so as to make the cryoablation operation of the specific parts of the human body more simple and convenient. The bending angle of the cryoballoon with the bending angle makes the contact surface of the cryoballoon and the tissue larger, and the ablation effect is better and more thorough. The shaped rod 7 can also rotate, so as to adjust the direction of the bending angle, which is convenient for operation.

[0046] The above only describes the preferred embodiments of the present application, and does not limit the implementation and protection scope of the present application. For those skilled in the art, it should be realized that any equivalent replacement and obvious change made according to the content of the present application should be included in the protection scope of the present application.

Claims

1. A cryoablation catheter with controllable ablation range, characterized in that, The device includes a displacement block (1), a moving rod (2), a cryogenic balloon (3), a return gas line (4), an inlet gas line (5), and a handle (6); the return gas line (4) is used for refrigerant reflux, and its distal end is fixedly and sealed to the proximal end of the cryogenic balloon (3); the inlet gas line (5) is used for refrigerant input, is located within the return gas line (4), and its distal end is located within the cryogenic balloon (3); the distal end of the displacement block (1) is fixedly connected to the distal end of the moving rod (2). The moving rod (2) is sealed to the distal end of the cryoballoon (3) and is movable relative to it. The proximal end of the moving rod (2) is sealed to the adapter (41) on the return gas line (4) and is movable relative to it. The cryoballoon (3) has a compressed state without refrigerant and an expanded state with refrigerant. When the cryoballoon (3) is in the compressed state, the moving rod (2) is moved to the proximal end, so that the displacement block (1) moves relative to the periphery of the cryoballoon (3) in the compressed state. The movable rod (2) is a hollow tube. The part of the distal end of the movable rod (2) inside the cryoballoon (3) is a low-hardness section (22). A shaping rod (7) is provided in the cavity of the movable rod (2). The shaping rod (7) and the movable rod (2) can move relative to each other. The distal end of the shaping rod (7) is set as a pre-shaped fixed shape part, and its pre-shaped shape has a bend.

2. The cryoablation catheter with controllable ablation range according to claim 1, characterized in that, The return air pipe (4) is provided with a return air pipe connector (42) at its near end, and the return air pipe connector (42) is fixedly connected to the handle (6).

3. The cryoablation catheter with controllable ablation range according to claim 1, characterized in that, An intake pipe connector (52) is provided at the near end of the intake pipe (5), and the intake pipe connector (52) is fixedly connected to the handle (6).

4. The cryoablation catheter with controllable ablation range according to claim 1, characterized in that, The air intake pipe (5) is provided with multiple refrigerant spray outlets (51) on the pipe wall of the cryosphere (3).

5. The cryoablation catheter with controllable ablation range according to claim 1, characterized in that, The displacement block (1) is a circular tube with a remote end seal.

6. The cryoablation catheter with controllable ablation range according to claim 1, characterized in that, The displacement block (1) is a round tube with a sealed distal end and a hollowed-out proximal end, including one or more hollowed-out portions (11). The hollowed-out portions (11) are radially opened and one end extends to the proximal end of the displacement block (1). The width of the hollowed-out portions (11) is constant.

7. The cryoablation catheter with controllable ablation range according to claim 1, characterized in that, The adapter (41) is provided with a fixing tooth (411), and the near end of the moving rod (2) is provided with a fixing seat (21). The fixing tooth (411) and the fixing seat (21) can mesh with each other.

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