A cryoablation system

Abstract

The present invention provides a cryoablation system, comprising a gas source, a rewarming pipeline, a freezing pipeline and an output connector; the rewarming pipeline is connected in parallel with the freezing pipeline; the freezing pipeline comprises a heat exchanger, the working fluid flows in from the inlet end of the heat exchanger, is converted into a freezing working fluid in the heat exchanger, and then flows out from the outlet end of the heat exchanger; the outlet end of the heat exchanger is connected with the output connector; and the system also comprises a one-way valve, the inlet end of the one-way valve is connected with the output connector, and the outlet end of the one-way valve is connected with the inlet end of the heat exchanger. When the pressure surges, the one-way valve is turned on, so that part of the freezing pipeline and part of the rewarming pipeline are connected, forming an air guide circuit, which alleviates the pressure surge caused by the phase change of the cold working fluid in the pipeline.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and in particular to a cryoablation system. Background Art

[0002] The cryoablation system includes cryoablation equipment and catheters. The cryoablation system refers to an instrument that uses low-temperature technology to freeze and destroy abnormal cells or diseased tissues, and is used to treat various cancers and arrhythmias. During cryoablation, the cryoablation device needs to be connected to an ablation device, such as an ablation needle, balloon catheter, etc. By introducing nitrogen, argon or carbon dioxide and other working fluids into the ablation device, low temperatures are generated at the treatment site, thereby freezing the diseased tissue. Cryoablation is a common interventional treatment technology in surgery. Compared with thermal ablation, it has the characteristics of high safety, less stimulation and damage to the natural cavity wall tissue of the human body, and less prone to complications. Therefore, this technology is increasingly used in clinical surgery.

[0003] There are two main methods for obtaining cryogenic fluid: one is through the Joule-Thomson throttling principle, and the other is through heat exchange. The former has high operating pressures and is less safe, while the latter is more convenient, efficient, safer, and more reliable. For example, heat exchange is used to obtain cryogenic fluid. A certain pressure of cryogenic fluid is passed through a heat exchanger, where it undergoes phase conversion to cryogenic fluid, which is then transported to the ablation device for cryotherapy.

[0004] After the refrigerant is condensed into a cryogenic refrigerant through a heat exchanger, it is delivered to the frozen end of the catheter, where it rapidly absorbs heat from the surrounding tissue, causing cryoablation at the frozen end. However, as the cryogenic refrigerant is transported through the pipeline after passing through the heat exchanger, it inevitably exchanges heat with the pipeline and the external environment, causing some of the refrigerant to vaporize, resulting in a pressure surge in the pipeline at the moment of discharge. This pressure surge can adversely affect the catheter, the delivery pipeline, and the components attached to it, shortening the service life of the pipeline components and their components. In severe cases, it can cause the catheter balloon to rupture, endangering the patient's life and health.

[0005] Therefore, how to solve the problem of pressure surge of the cryogenic medium during pipeline transportation and manufacture a stable, reliable cryoablation device with good refrigeration effect is an urgent problem to be solved. Summary of the Invention

[0006] The present invention provides a cryoablation system, which forms an air circulation by arranging a one-way valve between a freezing pipeline and a rewarming pipeline, thereby alleviating the pressure surged due to the phase change of the freezing working medium in the pipeline.

[0007] The present invention provides a cryoablation system, comprising a gas source, a rewarming pipeline, a freezing pipeline and an output connector; the rewarming pipeline is connected in parallel with the freezing pipeline; the freezing pipeline comprises a heat exchanger, the working fluid flows in from the inlet end of the heat exchanger, is converted into a freezing working fluid in the heat exchanger, and then flows out from the outlet end of the heat exchanger; the outlet end of the heat exchanger is connected with the output connector; and it also comprises a one-way valve, the inlet end of the one-way valve is connected with the output connector, and the outlet end of the one-way valve is connected with the inlet end of the heat exchanger. When the pressure surges, the one-way valve is turned on, so that part of the freezing pipeline and part of the rewarming pipeline are connected, forming a pressure-stabilizing passage.

[0008] Furthermore, the rewarming pipeline includes a rewarming solenoid valve and a first pressure sensor connected in sequence; the freezing pipeline includes a freezing solenoid valve and the heat exchanger connected in sequence; the inlet end of the one-way valve is connected between the rewarming solenoid valve and the first pressure sensor, and the outlet end of the one-way valve is connected between the freezing solenoid valve and the heat exchanger.

[0009] Furthermore, a switch device is provided on the retemperature pipeline, and when the switch device is opened, the retemperature pipeline is connected to the atmosphere to relieve pressure.

[0010] Furthermore, the output connector is connected between the rewarming pipeline and the freezing pipeline, and is connected to an external device; the output connector is used to transport the working medium in the freezing pipeline or the rewarming pipeline to the external device.

[0011] Furthermore, the one-way valve is used to guide the working medium in the freezing pipeline to the rewarming pipeline in a one-way manner.

[0012] Furthermore, a high-pressure proportional valve is provided at the outlet of the gas source, and the high-pressure proportional valve is connected to the second pressure sensor.

[0013] Furthermore, a third pressure sensor is provided at the output connector.

[0014] Furthermore, the one-way valve is an electric ball valve or an electric needle valve.

[0015] Furthermore, the output connector can be connected to at least three pipelines, and the three pipelines are the rewarming pipeline, the freezing pipeline and the pipeline of the external device.

[0016] Furthermore, the present invention provides a cryoablation system, comprising a gas source, a rewarming pipeline, a freezing pipeline and an output connector; the rewarming pipeline is connected in parallel with the freezing pipeline; the freezing pipeline comprises a heat exchanger, the working fluid flows in from the inlet end of the heat exchanger, is converted into a freezing working fluid in the heat exchanger, and then flows out from the outlet end of the heat exchanger; the outlet end of the heat exchanger is connected to the output connector; at least two pressure relief devices are connected to the rewarming pipeline, the pressure relief device comprises a unloading valve and a pressure relief solenoid valve, the unloading valve is connected to the atmosphere, the pressure relief solenoid valve is arranged between the rewarming pipeline and the unloading valve, and the corresponding unloading valve is controlled to open according to the needs of the external equipment of the cryoablation system.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects:

[0018] 1. In the prior art, the freezing and rewarming pipelines function independently, operating independently when the pipelines are open. This causes a surge in pipeline pressure during a phase change in the refrigerant, requiring only external pressure relief to ensure pipeline safety. This surge in pressure cannot be effectively controlled. The present invention incorporates a one-way valve between the freezing and rewarming pipelines, creating an internal air-guiding loop. This mitigates the pressure surge caused by the refrigerant phase change within the pipelines, stabilizes the system's operating pressure, and ensures pressure safety and operational efficiency.

[0019] 2. Set up multiple pressure relief devices, each pressure relief device corresponds to a certain type of catheter. After the system identifies the type of catheter, it controls the corresponding pressure relief device to open, making the system more selective. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0021] Figure 1 Shown is a schematic diagram of the connection relationship of a cryoablation system according to an embodiment of the present invention.

[0022] Figure 2 Shown is a schematic diagram of the connection relationship of a cryoablation system according to another embodiment of the present invention.

[0023] Figure 3 Shown is a pressure-time graph for a cryoablation system without a one-way valve.

[0024] Figure 4 Shown is a pressure-time graph of a cryoablation system equipped with a one-way valve.

[0025] Figure markings: gas source 11, rewarming pipeline 12, freezing pipeline 13, output connector 14, rewarming solenoid valve 121, first pressure sensor 122, freezing solenoid valve 131, heat exchanger 132, one-way valve 16, pressure relief device 17, unloading valve 171, pressure relief solenoid valve 172, high-pressure proportional valve 18, second pressure sensor 19, third pressure sensor 20, external equipment 21, switching device 22. DETAILED DESCRIPTION

[0026] Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. In the following description, when referring to the drawings, like numbers in different figures represent like or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all possible embodiments consistent with the present invention. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present invention, as detailed in the appended claims.

[0027] The terms used in the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. Unless otherwise defined, the technical or scientific terms used in the present invention should have the usual meaning understood by people with ordinary skills in the field to which the present invention belongs. The words "include" or "comprise" and the like used in the specification and claims of the present invention mean that the elements or objects appearing before "include" or "comprise" include the elements or objects listed after "include" or "comprise" and their equivalents, and do not exclude other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, and may include electrical connections, whether direct or indirect.

[0028] In the present invention, the inlet end and the outlet end are determined by the flow direction of the working medium. The inlet end refers to the end where the working medium flows into the component, and the outlet end refers to the end where the working medium flows out of the component.

[0029] The terms used in this invention are for the purpose of describing specific embodiments only and are not intended to limit the invention. The singular forms "a," "an," and "the" used in this invention and the appended claims are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0030] Example 1:

[0031] like Figure 1As shown, the present invention provides a cryoablation system, comprising: a gas source 11, a rewarming pipeline 12 and a freezing pipeline 13 connected in parallel, and an output connector 14, which are connected in sequence. The rewarming pipeline 12 includes a rewarming solenoid valve 121 and a first pressure sensor 122 connected in sequence; the freezing pipeline 13 includes a freezing solenoid valve 131 and a heat exchanger 132 connected in sequence; and further comprises a one-way valve 16, the inlet end of the one-way valve 16 being connected between the rewarming solenoid valve 121 and the first pressure sensor 122, and the outlet end of the one-way valve 16 being connected between the freezing solenoid valve 131 and the heat exchanger 132, so that gas can be guided from the rewarming pipeline 12 to the freezing pipeline 13 at the one-way valve 16; the output connector 14 is at least a three-way connector, the inlet end of which is connected to the rewarming pipeline 12, the outlet end of which is connected to the freezing pipeline 13, and the third end of which is used to connect to an external device 21 such as a freezing catheter or a freezing probe.

[0032] When the cryoablation system is started, after the working fluid is released from the gas source 11, the freezing solenoid valve 131 of the freezing pipeline 13 is opened, the rewarming solenoid valve 121 is closed, and the one-way valve 16 prevents the working fluid from flowing directly through the rewarming pipeline 12. After the working fluid passes through the heat exchanger 132, it condenses to form a frozen working fluid, which is then transported to the output connector 14 under pressure. Since the external device 21 of the output connector 14 is exposed to a room temperature environment, part of the frozen working fluid will evaporate during transportation to form a gaseous frozen working fluid, causing a surge in the working pressure of the freezing pipeline 13. The one-way valve 16 is set to connect part of the freezing pipeline 13 with part of the rewarming pipeline 12, forming an air guide circuit, that is, the working fluid passes through the heat exchanger 132-output connector 14-first pressure sensor 122-one-way valve 16-heat exchanger 132. This gas-guiding circuit mitigates the surge in pipeline pressure caused by the cryogenic refrigerant transforming into a gaseous state through heat exchange with the environment, thereby achieving a stable pressure. When the cryoablation system is rewarming, the rewarming solenoid valve 121 on the rewarming pipeline 12 is opened, and the freezing solenoid valve 131 is closed. The refrigerant flows directly through the rewarming pipeline 12 to the output connector 14. Because the refrigerant does not pass through the heat exchanger 132 to be converted into a cryogenic refrigerant, its temperature is higher than that of the refrigerant that passes through the heat exchanger 132, achieving a rewarming effect, enhancing the cryoablation effect and reducing complications.

[0033] The one-way valve 16 can be an integrated electromagnetic control device to remotely control the opening and closing of the one-way valve 16. The one-way valve 16 is preferably a low-temperature resistant electronic component with an on-off function, such as an electric ball valve or an electric needle valve. When such an electronic component is used, the electronic component must be opened or closed simultaneously with the cryoelectric solenoid valve 131 to achieve the same effect as the one-way valve 16.

[0034] A high-pressure proportional valve 18 and a second pressure sensor 19 are provided at the gas source 11. The second pressure sensor 19 works together with the high-pressure proportional valve 18. The second pressure sensor 19 is used to measure the outlet pressure of the working fluid when it comes out of the gas source 11. The high-pressure proportional valve 18 is used to achieve precise control of the outlet pressure and / or flow of the working fluid. After the second pressure sensor 19 feeds back the outlet pressure to the controller, the flow and / or pressure of the working fluid is adjusted through the high-pressure proportional valve 18 to ensure the freezing effect and safety of the cryoablation system.

[0035] A third pressure sensor 20 is provided at the output connector 14. The third pressure sensor 20 can measure the pressure at the output connector 14 and can also feed back pressure data to the controller, thereby controlling the high-pressure proportional valve 18 to make corresponding adjustments. In addition, when the value monitored by the third pressure sensor 20 exceeds a preset pressure threshold, the controller can also issue an alarm through a connected alarm. On the one hand, the working fluid becomes a cryogenic working fluid after passing through the heat exchanger 132, and the pressure in the pipeline and conduit will change. The third pressure sensor 20 can monitor the pressure changes and, based on the dynamic pressure changes, enable the system to issue an alarm and control the flow of the working fluid. On the other hand, the third pressure sensor 20 is the connection point between the cryoablation system and the external device 21. The safe operating pressure of different types and specifications of cryoablation external devices 21 varies. This configuration can ensure the safe use of the cryoablation external device 21. In addition, the output connector 14 can also be a four-way connector, with the third pressure sensor 20 integrated into the output connector 14 to improve system integration.

[0036] The rewarming line 12 is connected to a switch device 22, which is connected to the atmosphere to relieve pressure. The switch device 22 may be a solenoid valve connected to a controller, which opens or closes the solenoid valve based on pressure data feedback from a first pressure sensor 122 of the rewarming line 12. The switch device 22 may also be configured to have a safety pressure threshold set for the system, which automatically releases pressure when the safety valve exceeds the threshold.

[0037] Example 2:

[0038] like Figure 3As shown, unlike Example 1, Example 2 utilizes multiple unloading valves to stabilize pressure and balance pressure fluctuations within the pipeline. The rewarming pipeline 12 is connected to at least two pressure relief devices 17, each comprising a combination of an unloading valve 171 and a pressure relief solenoid valve 172. When a cryoablation system is used with multiple catheters or probes (i.e., catheters or probes connected to the output connector 14), multiple unloading valves 171 can be installed in the rewarming pipeline 12. Each unloading valve 171 corresponds to a specific catheter model, and the threshold of each unloading valve 171 is determined by the operating pressure of its corresponding catheter. A pressure relief solenoid valve 172 or other on / off component is positioned between the unloading valve 171 and the rewarming pipeline 12. Once the device identifies the catheter model, it controls the corresponding pressure relief solenoid valve 172 and the cryo solenoid valve 131 to open simultaneously, while the other pressure relief solenoid valves 172 close. This configuration provides a highly selective system.

[0039] Figure 3 It is a graph showing the change of working pressure with freezing time when the one-way valve 16 is not provided. Figure 4 The graph is a variation graph with a one-way valve 16. Comparing the two graphs, it can be seen that the system with the one-way valve 16 has a smaller operating pressure fluctuation range than the system without the one-way valve 16, and is closer to the set pressure of the system. Therefore, the technical solution of the present invention has a better pressure stabilization effect.

[0040] Other embodiments of the present invention will readily occur to those skilled in the art after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow from the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the invention being indicated by the following claims.

[0041] It should be understood that the present invention is not limited to the exact construction described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A cryoablation system comprising a gas source connected in sequence, a rewarming pipeline and a freezing pipeline connected in parallel, and an output connector; The refrigeration pipeline includes a heat exchanger, the working medium flows into the inlet end of the heat exchanger, is converted into a refrigeration working medium in the heat exchanger, and then flows out of the outlet end of the heat exchanger; the outlet end of the heat exchanger is connected to the output connector; It is characterized by: It also includes a one-way valve, the inlet end of the one-way valve is connected to the rewarming pipeline, and the outlet end of the one-way valve is connected to the inlet end of the heat exchanger. The one-way valve is used to unidirectionally guide the working medium in the freezing pipeline to the rewarming pipeline. The working medium is released from the gas source, condenses to form a freezing working medium after heat exchange in the heat exchanger, and the freezing working medium is transported to the output connector under pressure. When part of the freezing working medium evaporates to form a gaseous freezing working medium during transportation, causing a surge in the pressure of the freezing pipeline, the one-way valve is turned on, so that part of the freezing pipeline and part of the rewarming pipeline are connected to form a pressure-stabilizing passage.

2. The cryoablation system according to claim 1, wherein: The rewarming pipeline includes a rewarming solenoid valve and a first pressure sensor connected in sequence; the freezing pipeline includes a freezing solenoid valve and the heat exchanger connected in sequence; the inlet end of the one-way valve is connected between the rewarming solenoid valve and the first pressure sensor, and the outlet end of the one-way valve is connected between the freezing solenoid valve and the heat exchanger.

3. The cryoablation system according to claim 1, wherein: A switch device is provided on the retemperature pipeline. When the switch device is turned on, the retemperature pipeline is connected to the atmosphere to relieve pressure.

4. The cryoablation system according to claim 1, wherein: The output connector is connected between the rewarming pipeline and the freezing pipeline, and is connected to an external device; the output connector is used to transport the working medium in the freezing pipeline or the rewarming pipeline to the external device.

5. The cryoablation system according to claim 1, wherein: A high-pressure proportional valve is provided at the outlet of the gas source, and the high-pressure proportional valve is connected to the second pressure sensor.

6. The cryoablation system according to claim 4, characterized in that: A third pressure sensor is provided at the output joint.

7. The cryoablation system according to claim 1, wherein: The one-way valve is an electric ball valve or an electric needle valve.

8. The cryoablation system according to claim 4, wherein: The output connector can be connected to at least three pipelines, and the three pipelines are the rewarming pipeline, the freezing pipeline and the pipeline of the external device.

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