Pulmonary artery denervation ablation catheter, ablation method and ablation system
Patent Information
- Application Number
- CN202610737195.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-05-26
- Publication Date
- 2026-09-15
Smart Images
Figure CN122744879A_ABST
Abstract
Description
Technical Field
[0001] This application relates to a pulmonary artery denervation ablation catheter, ablation method, and ablation system, belonging to the field of medical device technology. Background Technology
[0002] Pulmonary artery denervation (PADN) is an interventional treatment method that reduces pulmonary artery pressure by ablating the sympathetic plexus on the adventitia of the pulmonary artery. It is mainly used for clinical intervention of pulmonary hypertension. With the development of interventional cardiology techniques, catheter ablation has gradually become an important research direction in this field, and related ablation catheter devices have been continuously developed and improved.
[0003] In existing pulmonary artery denervation ablation catheters, a common approach employs a structure design with multiple discrete, independent electrodes arranged along a ring-shaped support framework. This type of catheter typically uses a shape memory alloy framework, utilizing the elastic restoring force of the metal to propel the electrodes outwards, bringing them into contact with the inner wall of the pulmonary artery. Radiofrequency energy is then delivered through each electrode for point-like ablation. However, because this structure relies on the material's own elastic restoring force for adhesion, the contact state between the electrodes and the vessel wall is affected by factors such as changes in the vessel's inner diameter and curvature, as well as blood flow impact. In practice, it is difficult to maintain uniform contact pressure between the electrodes, and some electrodes may experience insufficient contact, resulting in unablated areas between adjacent ablation points. Furthermore, because the electrodes are independent and spaced apart, the continuity between multiple ablation points is structurally difficult to guarantee.
[0004] In the aforementioned multi-electrode schemes, dedicated temperature sensors are typically not integrated. Tissue temperature information during the ablation process mainly relies on indirect calculations by the ablation instrument through monitoring changes in output power and electrode-tissue interface impedance. It is impossible to directly obtain real-time temperature data at each point in the ablation area, making it difficult to respond promptly to abnormal increases in local temperature.
[0005] Existing pulmonary artery denervation ablation catheters typically lack intraoperative neurological function assessment capabilities. The selection of ablation targets relies primarily on the surgeon's empirical judgment of the pulmonary artery anatomy, mainly using DSA-guided anatomical localization, lacking objective localization criteria based on neurological function status. Similarly, after ablation, the immediate effectiveness of the procedure lacks effective intraoperative verification methods; whether denervation is adequate usually requires indirect assessment through postoperative follow-up, making it impossible to obtain objective feedback on the outcome immediately during the procedure.
[0006] Therefore, existing pulmonary artery denervation ablation catheters have technical limitations in ensuring electrode uniformity, real-time monitoring of ablation area temperature, and objective assessment of intraoperative ablation effect. There is a need to provide a pulmonary artery denervation ablation catheter that can improve the above-mentioned shortcomings. Summary of the Invention
[0007] The purpose of this invention is to provide a pulmonary artery denervation ablation catheter, ablation method, and ablation system to solve the following technical problems existing in the prior art: (1) Existing pulmonary artery denervation ablation catheters use shape memory alloy support skeletons to passively adhere to the vessel wall by relying on elastic recovery force. The contact pressure between the electrode and the vessel wall is affected by factors such as changes in vessel inner diameter, curvature and blood flow impact, making it difficult to maintain uniformity. This results in leaks in the ablation area due to insufficient contact, making it impossible to achieve uniform and continuous ablation in the entire circumference. (2) Existing catheters use multiple discrete independent electrodes for point ablation. There is a certain distance between the electrodes, and the continuity between adjacent ablation points is difficult to guarantee structurally, resulting in ablation blind zone. (3) Existing catheters do not integrate dedicated temperature sensors. During the ablation process, tissue temperature information depends on the ablation instrument to indirectly calculate by monitoring the output power and the change in electrode-tissue interface impedance. It is impossible to directly obtain real-time temperature data of each point in the ablation area. It is difficult to respond in time to abnormal local temperature rise, and there are safety risks of vascular perforation, thrombosis and long-term stenosis. (4) Existing catheters do not have intraoperative neurological function assessment methods. The selection of ablation targets mainly depends on the surgeon's empirical judgment of the pulmonary artery anatomy and lacks objective positioning basis based on neurological function status. After ablation, there is also a lack of effective intraoperative verification methods. Whether denervation is sufficient usually needs to be indirectly judged by postoperative follow-up.
[0008] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a pulmonary artery denervation ablation catheter, comprising a catheter body; An expandable support is provided at the distal end of the catheter body, and an inflatable lumen communicating with the expandable support is provided inside the catheter body. The outer surface of the expandable support is spirally wound with a spiral ablation electrode. The spiral ablation electrode is a continuous spiral conductive element. The spiral ablation electrode is electrically connected to an external ablation energy source through a single wire. The spiral ablation electrode is also electrically connected to an external electrical stimulation generator through a wire. A distributed temperature sensing array is provided on the spiral ablation electrode. The distributed temperature sensing array includes multiple temperature sensing elements distributed along the spiral ablation electrode. The multiple temperature sensing elements are signal-connected to an external monitoring unit. The spiral ablation electrode is electrically connected to the external electrical stimulation generator, and the external electrical stimulation generator outputs an electrical stimulation signal to the outside through the spiral ablation electrode; The catheter body is also provided with a pressure transmission channel, which extends along the axial direction of the catheter body, and the proximal end of the pressure transmission channel is provided with an interface for communicating with an external pressure transducer.
[0009] This invention employs an expandable support structure as the supporting structure for the spiral ablation electrode. Upon inflation, this structure generates a uniform radial force that actively presses the spiral ablation electrode against the inner wall of the pulmonary artery, achieving uniform circumferential adhesion. The spiral ablation electrode, with its continuous spiral conductive elements, forms a 360° continuous strip-shaped ablation area in a single operation, eliminating blind spots between multiple ablation points. A distributed temperature sensor array monitors the temperature at each point within the ablation area in real time, providing data support for closed-loop temperature control. Electrical stimulation is used before and after ablation to locate sympathetic nerve enrichment targets and verify denervation effects, respectively. A pressure conduction channel transmits pulmonary artery pressure, providing a basis for intraoperative hemodynamic assessment.
[0010] Furthermore, the expandable support is a balloon, and the inflatable lumen is filled with a liquid or gaseous medium. After inflation, the balloon generates a uniform radial expansion force, actively and evenly pressing the spiral ablation electrode against the inner wall of the pulmonary artery, effectively adapting to irregular vascular morphology and ensuring consistent contact pressure at all points on the electrode.
[0011] Furthermore, the plurality of temperature sensing elements are uniformly distributed along the circumference of the spiral ablation electrode, and the temperature sensing elements are thermocouples or thermistors. The uniform circumferential distribution of temperature sensing elements enables distributed and accurate temperature measurement without blind spots throughout the entire circumference. Thermocouples or thermistors are mature miniaturized temperature sensor devices with fast response speed and high temperature measurement accuracy, making them suitable for integration onto the spiral ablation electrode.
[0012] Furthermore, the external electrical stimulation generator has a mapping mode and a verification mode. In the mapping mode, the external electrical stimulation generator outputs a high-frequency, low-energy electrical stimulation signal through the spiral ablation electrode to locate sympathetic nerve enrichment target points. In the verification mode, the external electrical stimulation generator outputs an electrical stimulation signal again through the spiral ablation electrode with the same parameters as in the mapping mode to verify the denervation effect. The mapping mode determines whether the stimulation point is rich in sympathetic nerves by observing the subject's heart rate response, achieving objective target point localization based on neural function status. In the verification mode, after ablation, stimulation is performed again with the same parameters, and the disappearance of the heart rate response determines whether denervation is sufficient, achieving real-time closed-loop assessment during the procedure.
[0013] Preferably, the high-frequency, low-energy electrical stimulation signal output in the mapping mode is a high-frequency, low-energy pulse signal. High-frequency, low-energy pulse signals can effectively stimulate the sympathetic nervous system to produce physiological responses while minimizing tissue damage, making them suitable for intraoperative neurological function assessment.
[0014] Furthermore, the spacing between adjacent turns of the spiral ablation electrode is uniformly distributed along the axial direction. This uniform spacing ensures that the spiral ablation electrode forms a uniformly distributed continuous ablation band within the axial range of the pulmonary artery, avoiding uneven local ablation energy density.
[0015] Furthermore, the outer surface of the catheter body is provided with an insulating coating, which covers the area on the outer surface of the catheter body excluding the working surface of the spiral ablation electrode. The insulating coating can effectively prevent ablation energy from leaking into non-target areas, concentrating the ablation energy on the area where the working surface of the spiral ablation electrode contacts the blood vessel wall, thereby improving the accuracy and safety of ablation.
[0016] Furthermore, the proximal end of the catheter body is provided with a multi-lumen interface, which is connected to the filling lumen, the lead wire channel, and the pressure transmission channel, respectively. The multi-lumen interface leads all functional channels within the catheter to the proximal end, facilitating connection with external ablation energy sources, electrical stimulation generators, pressure transducers, and filling medium injection devices, thereby enabling convenient docking of the multifunctional integrated catheter with external equipment.
[0017] The present invention also provides a method for pulmonary artery denervation ablation, including the step of delivering an ablation catheter to a target location in the pulmonary artery, and further including the following steps: Filling and attaching step: Fill the expandable support body of the ablation catheter with a medium to expand the expandable support body, and press the spiral ablation electrode, which is spirally wound on the outer surface of the expandable support body, evenly against the inner wall of the pulmonary artery. Neuromapping steps: Electrical stimulation signals are output through the spiral ablation electrodes, and sympathetic nerve enrichment target points are determined based on the subject's heart rate response; Ablation steps: Ablation energy is output at the sympathetic nerve enrichment target point through the spiral ablation electrode to form a continuous circumferential ablation zone; Effect verification steps: After ablation is completed, an electrical stimulation signal is output again through the spiral ablation electrode, and the denervation effect is verified based on the heart rate change.
[0018] This method achieves objective intraoperative assessment of the entire process from target localization to effect confirmation through a complete closed-loop procedure, including active balloon inflation and wall application, precise target localization via nerve electrical stimulation, one-time circumferential ablation with helical electrodes, and immediate post-ablation effect verification.
[0019] Furthermore, during the ablation step, temperature signals from multiple temperature sensing elements distributed along the spiral ablation electrode are acquired in real time. When the temperature detected by any of the temperature sensing elements exceeds a preset threshold, the output power of the ablation energy is automatically reduced or cut off. This step achieves real-time temperature control through closed-loop feedback of the distributed temperature sensing array, preventing localized overheating at any location in the ablation area and significantly improving ablation safety.
[0020] Furthermore, in the effect verification step, if the heart rate change is greater than a preset threshold, denervation is deemed insufficient, and the ablation step and the effect verification step are repeated until the heart rate change is lower than the preset threshold. This step establishes an iterative verification and additional ablation mechanism for the ablation effect, ensuring that denervation is fully completed and avoiding the need for a second surgery due to insufficient ablation in one operation.
[0021] The present invention also provides a pulmonary artery denervation ablation system, including an ablation energy source, and further including: the above-mentioned pulmonary artery denervation ablation catheter; An electrical stimulation generator is electrically connected to the spiral ablation electrode of the ablation catheter, and the electrical stimulation generator outputs an electrical stimulation signal through the spiral ablation electrode; A pressure transducer is fixedly connected to the proximal interface of the pressure transmission channel of the ablation catheter, and the pressure transducer converts the fluid pressure transmitted by the pressure transmission channel into a pressure signal output. The control input terminal of the ablation energy source is electrically connected to the spiral ablation electrode of the ablation catheter and the signal output terminal of the distributed temperature sensing array of the ablation catheter, respectively. The ablation energy source adjusts the output power of the ablation energy according to the temperature signal output by the distributed temperature sensing array.
[0022] This ablation system organically integrates the ablation catheter with the ablation energy source, electrical stimulation generator, and pressure transducer. Each external device is connected to the corresponding functional channels inside the catheter through the multi-lumen interface at the proximal end of the catheter, forming a complete interventional treatment system with five major functions: active wall adhesion, continuous ablation, distributed temperature control, nerve mapping and verification, and real-time pressure monitoring.
[0023] The beneficial effects that this application can produce include: 1) Significantly improved adhesion reliability and ablation integrity. The expandable support generates a uniform radial force after inflation, actively pressing the spiral ablation electrode against the inner wall of the pulmonary artery, eliminating the contact gaps caused by the passive adhesion method of shape memory alloys due to the curvature of the blood vessels and the impact of blood flow; the spiral ablation electrode can form a complete 360° uninterrupted circumferential ablation zone with a single discharge of continuous spiral conductive elements, structurally eliminating blind spots between multi-point ablation and ensuring the continuity and integrity of the ablation area.
[0024] 2) Achieving precise closed-loop treatment during surgery. The electrical stimulation mapping mode objectively locates sympathetic nerve enrichment targets through heart rate response, upgrading the selection of ablation targets from subjective judgment based on anatomical experience to objective localization based on the state of nerve function; the electrical stimulation verification mode immediately assesses the denervation effect after ablation. If the effect is insufficient, additional ablation can be performed on the spot, realizing a complete closed loop of "localization → ablation → verification → additional ablation" during surgery, avoiding secondary surgery due to the inability to assess the effect during surgery.
[0025] 3) Significantly improved ablation safety. The distributed temperature sensor array is uniformly distributed along the circumference of the spiral ablation electrode, which can acquire temperature data of each point in the ablation area in real time. When the temperature at any location exceeds the preset threshold, the ablation energy output power is automatically adjusted, which effectively prevents local overheating and reduces the risk of vascular perforation, thrombosis and long-term vascular stenosis. The safety assurance capability is significantly better than that of existing products that rely on power / impedance to indirectly infer temperature.
[0026] 4) The conduit structure is greatly simplified. The original multiple discrete and independent electrodes are replaced by a single continuous spiral conductive element. Combined with a single wire and a minimal solder joint connection method, the electrical connection structure of the conduit is simplified from a complex form with multiple electrodes, multiple wires, and multiple solder joints to a minimal structure. This reduces the difficulty of the manufacturing process and improves product consistency and reliability.
[0027] 5) It has the function of real-time intraoperative pressure monitoring. The catheter is embedded with a pressure transmission channel and connected to an external pressure transducer, which can monitor changes in pulmonary artery pressure in real time throughout the operation. This provides immediate hemodynamic evidence for assessing the adequacy of ablation and whether additional treatment is needed, further improving the intraoperative assessment system. Attached Figure Description
[0028] Figure 1 A schematic diagram of the overall structure of the pulmonary artery denervation ablation catheter; Figure 2 for Figure 1 A magnified view of the distal portion of the middle catheter; Figure 3 This is a schematic diagram of the multi-lumen interface at the proximal end of the catheter body; Figure 4 A side sectional view of the expandable support structure; Figure 5 This is a schematic diagram of the expandable support before it is fully inflated. Figure 6 for Figure 1 A schematic diagram of the cross-section of the main body of the conduit; Figure 7 A schematic diagram illustrating the process of switching between the mapping mode and the verification mode of an external electrical stimulation generator; Figure 8 This is a flowchart illustrating the pulmonary artery denervation ablation procedure. Figure 9 A schematic diagram of the connections in the pulmonary artery denervation ablation system; Figure label: 1-Catheter body; 2-Expandable support; 3-Inflation lumen; 4-Helical ablation electrode; 5-Wire; 6-Multi-lumen interface; 7-Temperature sensor array; 8-Temperature sensor element; 9-Pressure transmission channel; 10-Insulating coating; 11-Ablation energy source; 12-Electrical stimulation generator; 13-Pressure transducer; 14-Inflation connector; 15-Pressure measuring connector; 16-Wire connector. Detailed Implementation
[0029] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.
[0030] It should be noted that the following embodiments are all based on... Figure 1-9 As shown: Example 1 Reference Figure 1 and Figure 2 A pulmonary artery denervation ablation catheter includes a catheter body 1 and a functional integrated segment disposed at the distal end of the catheter body 1. The catheter body 1 is generally elongated and tubular, with an outer diameter comparable to that of conventional interventional catheters, possessing sufficient axial pushing force and flexibility, and can be delivered to the target segment of the pulmonary artery via a guidewire and peripheral vein. An expandable support 2, which is a balloon, is disposed at the distal end of the catheter body 1. The balloon is made of compliant or semi-compliant polymer material, folded and stored tightly against the outer surface of the catheter body 1 in its uninflated state, and expands radially outward after inflation, generating a uniform radial expansion force. An inflation lumen 3 is provided within the catheter body 1, extending axially along the catheter body 1. The distal end of the inflation lumen 3 communicates with the inner lumen of the balloon, and the proximal end of the inflation lumen 3 is led out through an interface at the proximal end of the catheter body 1. Liquid or gaseous media can be injected into the balloon through this interface to inflate it. After the balloon is inflated, it generates a uniform radial force, which actively and evenly presses the spiral ablation electrode 4 wrapped around the outer surface of the balloon against the inner wall of the pulmonary artery. This effectively adapts to the irregular vascular morphology and ensures that the contact pressure of the electrode is consistent throughout, thereby eliminating contact gaps and ablation leaks caused by passive adhesion.
[0031] Reference Figures 1-2The spiral ablation electrode 4 is a continuous spiral conductive element, consisting of a platinum-iridium alloy conductive wire spirally wound around the outer surface of the balloon. Each end of the spiral ablation electrode 4 has an electrical connection point, which is led out through a wire 5 to the multi-lumen interface 6 near the proximal end of the catheter body 1, connecting to an external ablation energy source. The spiral ablation electrode 4, with its continuous spiral structure, can form a 360° continuous band-shaped ablation area circumferentially in the pulmonary artery with a single discharge, eliminating blind spots between multiple ablation points and ensuring the continuity and integrity of the ablation area. The spacing between adjacent turns of the spiral ablation electrode 4 is uniformly distributed along the axial direction, ensuring that the spiral ablation electrode 4 forms a uniformly distributed continuous ablation band within the axial range of the pulmonary artery, avoiding uneven local ablation energy density. The spiral ablation electrode 4 is also electrically connected to an external electrical stimulation generator via a wire, reusing the spiral ablation electrode 4 as an electrical stimulation output electrode, switching between ablation mode and electrical stimulation mode to achieve neural mapping and ablation effect verification functions.
[0032] Reference Figure 5 A temperature sensing array 7 is provided on the spiral ablation electrode 4. The temperature sensing array 7 includes multiple temperature sensing elements 8 distributed along the spiral ablation electrode 4. The multiple temperature sensing elements 8 are uniformly distributed circumferentially along the spiral ablation electrode 4. The temperature sensing elements 8 are thermocouples or thermistors. The temperature sensing elements 8 are fixed to the outer surface of the spiral ablation electrode 4 by conductive adhesive bonding or mechanical clamping. The signal wires of each temperature sensing element 8 are led out along the internal wiring of the conduit body 1 to the proximal multi-cavity interface 6, and are connected to the signal of the external monitoring unit. The uniform circumferential distribution of the temperature sensing elements 8 can realize distributed accurate temperature measurement without blind spots in the entire circumference. Thermocouples or thermistors are mature miniaturized temperature sensor devices with fast response speed and high temperature measurement accuracy, which are suitable for integration on the spiral ablation electrode 4. When any temperature sensing element 8 detects a temperature exceeding a preset threshold, the external monitoring unit transmits a signal to the ablation energy source. The ablation energy source automatically reduces or cuts off the output power of the ablation energy, thereby achieving closed-loop precise temperature control, effectively preventing local overheating, and reducing the risk of vascular perforation, thrombosis, and long-term stenosis.
[0033] Reference Figure 6 The catheter body 1 is also equipped with a pressure conduction channel 9, which is an independent fluid conduction cavity that extends and penetrates along the axial direction of the catheter body 1. The distal opening of the pressure conduction channel 9 is located on the proximal side of the balloon and is in fluid communication with the pulmonary artery lumen. The proximal end of the pressure conduction channel 9 is equipped with an interface for communication with an external pressure transducer. This interface is a Luer-locked interface. Through this interface, it is connected to an external standard pressure transducer. The pressure transducer converts the fluid pressure conducted by the pressure conduction channel 9 into a pressure signal and outputs it to the monitor, realizing real-time pulmonary artery pressure monitoring during the operation and providing immediate hemodynamic evidence for assessing the adequacy of ablation and whether additional treatment is needed.
[0034] Reference Figure 3 The proximal end of the catheter body 1 is provided with a multi-lumen interface 6, which is connected to the filling lumen 3, the lead channel, and the pressure transmission channel 9. Specifically, the multi-lumen interface 6 includes a filling connector 14, a pressure measuring connector 15, and a lead connector 16. The filling connector 14 is connected to the filling lumen 3, the pressure measuring connector 15 is connected to the pressure transmission channel 9, and the lead connector 16 is connected to the lead 5 of the lead channel. The multi-lumen interface 6 unifies the various functional channels within the catheter body 1 to the proximal end, facilitating connection with external ablation energy sources, electrical stimulation generators, pressure transducers, and filling medium injection devices, thereby enabling convenient docking of the multifunctional integrated catheter with external equipment. The outer surface of the catheter body 1 is provided with an insulating coating 10, which covers the area on the outer surface of the catheter body 1 except for the working surface of the spiral ablation electrode 4. The insulating coating 10 effectively prevents the ablation energy from leaking into non-target areas, concentrating the ablation energy on the area where the working surface of the spiral ablation electrode 4 contacts the blood vessel wall, improving the accuracy and safety of ablation.
[0035] Example 2 Reference Figures 4-5 This embodiment, based on Embodiment 1, further discloses a preferred embodiment of the expandable support 2. The expandable support 2 is a balloon made of polyurethane or nylon material, and the filling medium is physiological saline or diluted contrast agent. After inflation, the outer diameter of the balloon matches the inner diameter of the target pulmonary artery. When the filling lumen 3 is filled with liquid medium, physiological saline is injected into the filling lumen 3 through a syringe or filling pump via the proximal interface, causing the balloon to expand from its folded and stored state to its working state. The balloon inflation pressure is 1-3 atm. Within this pressure range, the balloon can generate sufficient radial expansion force to uniformly press the spiral ablation electrode 4 against the inner wall of the pulmonary artery, achieving 360° seamless circumferential adhesion. When the inflation pressure is below 1 atm, the radial force is insufficient, and the electrode adhesion effect is inadequate; when the inflation pressure is above 3 atm, there is a risk of vascular injury. Therefore, the inflation pressure range of 1-3 atm is the preferred working range for active balloon adhesion. When filling the cavity 3 with a gaseous medium, carbon dioxide gas can be used as the filling medium to reduce the risk of gas embolism. Figure 4 A side sectional view of the expandable support structure is shown. Figure 5 This is a schematic diagram of the expandable support before inflation. Before inflation, the balloon is folded tightly against the catheter body 1. After inflation, the balloon expands uniformly, and the spiral ablation electrode 4 is pressed evenly against the inner wall of the pulmonary artery, with uniform pressure distribution at the wall.
[0036] Example 3 Reference Figure 5This embodiment, based on Embodiment 1, further discloses a preferred embodiment of the temperature sensing array 7. The temperature sensing array 7 includes multiple temperature sensing elements 8 evenly distributed circumferentially along the spiral ablation electrode 4. The number of temperature sensing elements 8 is 4 to 9, and the circumferential spacing angle between adjacent temperature sensing elements 8 is approximately 40° to 90°, ensuring full circumferential temperature measurement coverage without blind spots. When the temperature sensing element 8 is a thermocouple, a K-type or T-type miniature thermocouple is used. The thermal junction of the thermocouple is fixed to the outer surface of the spiral ablation electrode 4 with conductive adhesive, and the signal wire is led out along the inner wall of the conduit body 1 to the proximal multi-cavity interface 6. When the temperature sensing element 8 is a thermistor, a negative temperature coefficient thermistor is used, fixed to the spiral ablation electrode 4 by mechanical clamping or embedded packaging. During ablation, each temperature sensing element 8 collects temperature data at its corresponding location in real time. When any temperature sensing element 8 detects a temperature exceeding a preset threshold (e.g., 60°C), the external monitoring unit sends a control command to the ablation energy source. The ablation energy source automatically reduces its output power or cuts off the ablation energy, ensuring that ablation is performed within a safe temperature range and effectively preventing vascular perforation, thrombosis, and long-term vascular stenosis caused by local overheating. By employing a configuration of 4 to 9 temperature sensing elements 8, full circumferential temperature measurement coverage is ensured while also taking into account the limitations of the catheter's internal wiring space, achieving a balance between temperature measurement accuracy and structural feasibility.
[0037] Example 4 Reference Figure 7This embodiment, based on Embodiment 1, further discloses a preferred implementation scheme for switching between the mapping mode and the verification mode of the external electrical stimulation generator. The external electrical stimulation generator has a mapping mode and a verification mode. The two modes are mutually exclusive and switched via a mode switching switch or software control, ensuring no signal interference occurs between the ablation mode and the electrical stimulation mode. In mapping mode, the external electrical stimulation generator outputs a high-frequency, low-energy electrical stimulation signal through the spiral ablation electrode 4. The high-frequency, low-energy electrical stimulation signal is a high-frequency, low-energy pulse signal with a frequency of 20–30 Hz, a voltage of 5–15 V, and a pulse width of 1–5 ms. If the stimulation point is rich in sympathetic nerves, it will induce a significant increase in the subject's heart rate (positive response, heart rate increase ≥10 bpm); if there is no significant change in heart rate, the site is not an effective target. By analyzing the strength of the heart rate response at each point, the physician determines the sympathetic nerve-rich target points, achieving objective target localization based on the neurological functional state, upgrading the traditional subjective judgment relying on anatomical experience to precise localization under electrophysiological navigation. After ablation, the system immediately switches to verification mode. The external electrical stimulation generator outputs an electrical stimulation signal again through the spiral ablation electrode 4 with the same parameters as in the mapping mode, applying the same frequency and voltage to the target point that was just ablated. If denervation is successful, the previously observed increase in heart rate will disappear, and the heart rate change will be less than 5 bpm, indicating that the nerve at that location has been effectively destroyed and the ablation is successful. If the heart rate change is still greater than or equal to 5 bpm, the denervation is considered insufficient, and additional ablation is required. By switching between mapping and verification modes, a complete closed loop of "localization → ablation → verification" is achieved during the procedure, enabling the surgeon to objectively assess the ablation effect in real time during the procedure, avoiding the need for a second surgery due to the inability to assess the effect during the procedure.
[0038] Example 5 Reference Figure 8 This embodiment discloses a method for pulmonary artery denervation ablation, which uses the pulmonary artery denervation ablation catheter described in Embodiment 1 and includes the following steps: Catheter delivery procedure: The ablation catheter is delivered along the guidewire through the peripheral vein to the target location in the pulmonary artery. Under DSA image guidance, it is confirmed that the distal balloon of the catheter is located in the target ablation segment.
[0039] Inflation and Adhesion Procedure: Inflate the expandable support 2 of the ablation catheter with a medium, inject physiological saline into the balloon through the inflation lumen 3, and inflate the expandable support 2 with a pressure of 1-3 atm. Then, press the spiral ablation electrode 4, which is spirally wound around the outer surface of the expandable support 2, evenly against the inner wall of the pulmonary artery. After confirming that the balloon is evenly inflated and the electrode is well adhered to the wall, proceed with subsequent operations.
[0040] Neuromapping steps: Switch to mapping mode, output high-frequency low-energy pulse electrical stimulation signals with a frequency of 20-30 Hz and a voltage of 5-15 V through spiral ablation electrode 4, monitor the subject's heart rate changes in real time, determine sympathetic nerve enrichment target points based on heart rate response, and mark sites with heart rate increase ≥10 bpm as positive target points, which are used as ablation target points.
[0041] Ablation Steps: Switch to ablation mode. Ablation energy is output at the sympathetic nerve enrichment target point via the spiral ablation electrode 4, forming a continuous circumferential ablation zone with a single discharge. During the ablation process, temperature signals from multiple temperature sensing elements 8 distributed along the spiral ablation electrode 4 are acquired in real time. When the temperature detected by any temperature sensing element 8 exceeds a preset threshold, the output power of the ablation energy is automatically reduced or cut off, achieving closed-loop precise temperature control. This prevents localized overheating at any location within the ablation area, significantly improving ablation safety.
[0042] Effect verification steps: After ablation, immediately switch to verification mode and output electrical stimulation signals again through the spiral ablation electrode 4 with the same parameters as in the mapping mode. Verify the denervation effect based on heart rate changes. If the heart rate change is less than 5 bpm, denervation is considered successful and ablation is complete; if the heart rate change is greater than or equal to the preset threshold, denervation is considered insufficient. Repeat the ablation and effect verification steps until the heart rate change is lower than the preset threshold, confirming that denervation is sufficient and ending the ablation process.
[0043] Catheter withdrawal procedure: After confirming satisfactory ablation results, aspirate the filling medium to restore the balloon to its folded state, and withdraw the ablation catheter from the body along the original path.
[0044] Through the above complete closed-loop operation process, an objective intraoperative assessment of the entire process from target localization to effect confirmation was achieved. An iterative verification and additional ablation mechanism for the ablation effect was established to ensure that denervation was fully completed and to avoid the need for a second operation due to insufficient ablation in one operation.
[0045] Example 6 Reference Figure 9 This embodiment discloses a pulmonary artery denervation ablation system, which includes an ablation energy source 11, a pulmonary artery denervation ablation catheter as described in Embodiment 1, an electrical stimulation generator 12, and a pressure transducer 13.
[0046] The ablation energy source 11 is a radiofrequency ablation device. The output end of the ablation energy source 11 is electrically connected to the spiral ablation electrode 4 through the wire channel of the proximal multi-lumen interface 6 of the catheter body 1. The control input end of the ablation energy source 11 is electrically connected to the signal output end of the distributed temperature sensor array 7. The ablation energy source 11 adjusts the output power of the ablation energy according to the temperature signal output by the distributed temperature sensor array 7 to achieve closed-loop temperature-controlled ablation.
[0047] The electrical stimulation generator 12 is electrically connected to the spiral ablation electrode 4 of the ablation catheter. The electrical stimulation generator 12 shares the lead wire channel of the spiral ablation electrode 4 with the ablation energy source 11 via a mode switching switch. The ablation mode and electrical stimulation mode are mutually exclusive to prevent signal interference. The electrical stimulation generator 12 outputs electrical stimulation signals through the spiral ablation electrode 4 and has the function of switching between mapping mode and verification mode, enabling intraoperative nerve mapping and localization and real-time verification of ablation effects.
[0048] The pressure transducer 13 is fixed to the proximal interface of the pressure conduction channel 9 of the ablation catheter via the Luer locking interface. The pressure transducer 13 converts the fluid pressure conducted by the pressure conduction channel 9 into a pressure signal output. The pressure signal is transmitted to the monitor to display the real-time pulmonary artery pressure waveform, providing immediate basis for intraoperative hemodynamic assessment.
[0049] Each external device is connected to the corresponding functional channels inside the catheter body 1 through the multi-lumen interface 6 at the proximal end of the catheter, forming a complete interventional treatment system with five major functions: active wall adhesion, continuous ablation, distributed temperature control, nerve mapping and verification, and real-time pressure monitoring.
[0050] Implementation principle: During use, the ablation catheter is first advanced along the guidewire to the target segment of the pulmonary artery. After confirming the location, physiological saline is injected into the balloon to 1–3 atm. The balloon inflates, generating a uniform radial force that actively presses the spiral ablation electrode 4 against the inner wall of the pulmonary artery, achieving 360° circumferential uniform contact. Subsequently, the system switches to mapping mode, and the electrical stimulation generator 12 outputs 20–30 Hz and 5–15 Hz stimulation signals through the spiral ablation electrode 4. High-frequency, low-energy pulsed electrical stimulation (V) is used to determine the sympathetic nerve enrichment target points based on the subject's heart rate response. After confirming the target points, the ablation mode is switched. The ablation energy source 11 outputs radiofrequency energy through the spiral ablation electrode 4, forming a 360° circumferential continuous ablation zone in one discharge. During the ablation process, the distributed temperature sensor array 7 monitors the temperature at each point in real time. When the temperature exceeds the threshold, the ablation energy source 11 automatically adjusts the output power to ensure safe ablation. After the ablation is completed, the mode is immediately switched to verification mode, and the target points are stimulated again with the same electrical stimulation parameters. The denervation effect is judged based on the heart rate change. If the effect is insufficient, additional ablation is performed on the spot until the denervation is fully completed. Throughout the procedure, the pressure transducer 13 monitors the pulmonary artery pressure in real time through the pressure transmission channel 9, providing immediate hemodynamic feedback. After confirming that the ablation effect is satisfactory, the balloon is withdrawn, the catheter is removed, and the procedure is completed.
[0051] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.
Claims
1. A pulmonary artery denervation ablation catheter, comprising a catheter body, characterized in that, An expandable support is provided at the distal end of the catheter body, and an inflatable lumen communicating with the expandable support is provided inside the catheter body. The outer surface of the expandable support is spirally wound with a spiral ablation electrode. The spiral ablation electrode is a continuous spiral conductive element. The spiral ablation electrode is electrically connected to an external ablation energy source through a single wire. The spiral ablation electrode is also electrically connected to an external electrical stimulation generator through a wire. A distributed temperature sensing array is provided on the spiral ablation electrode. The distributed temperature sensing array includes multiple temperature sensing elements distributed along the spiral ablation electrode. The multiple temperature sensing elements are signal-connected to an external monitoring unit. The spiral ablation electrode is electrically connected to the external electrical stimulation generator, and the external electrical stimulation generator outputs an electrical stimulation signal to the outside through the spiral ablation electrode; The catheter body is also provided with a pressure transmission channel, which extends along the axial direction of the catheter body, and the proximal end of the pressure transmission channel is provided with an interface for communicating with an external pressure transducer.
2. The pulmonary artery denervation ablation catheter of claim 1, wherein, The expandable support is a balloon, and the inflatable cavity is filled with a liquid or gaseous medium.
3. The pulmonary artery denervation ablation catheter of claim 1, wherein, The plurality of temperature sensing elements are evenly distributed along the circumference of the spiral ablation electrode, and the temperature sensing elements are thermocouples or thermistors.
4. The pulmonary artery denervation ablation catheter of claim 1, wherein, The external electrical stimulation generator has a mapping mode and a verification mode. In the mapping mode, the external electrical stimulation generator outputs a high-frequency, low-energy electrical stimulation signal through the spiral ablation electrode to locate the sympathetic nerve enrichment target point. In the verification mode, the external electrical stimulation generator outputs an electrical stimulation signal again through the spiral ablation electrode with the same parameters as in the mapping mode to verify the denervation effect. Preferably, the high-frequency low-energy electrical stimulation signal output in the calibration mode is a high-frequency low-energy pulse signal.
5. The pulmonary artery denervation ablation catheter according to claim 1, characterized in that, The spacing between adjacent turns of the spiral ablation electrode is uniformly distributed along the axial direction.
6. The pulmonary artery denervation ablation catheter according to claim 1, characterized in that, The outer surface of the catheter body is provided with an insulating coating, which covers the area on the outer surface of the catheter body except for the working surface of the spiral ablation electrode.
7. The pulmonary artery denervation ablation catheter according to claim 1, characterized in that, The proximal end of the catheter body is provided with a multi-lumen interface, which is connected to the filling lumen, the wire channel and the pressure transmission channel respectively.
8. A method for pulmonary artery denervation ablation, comprising the step of delivering an ablation catheter to a target location in the pulmonary artery, characterized in that, It also includes the following steps: Filling and attaching step: Fill the expandable support body of the ablation catheter with a medium to expand the expandable support body, and press the spiral ablation electrode, which is spirally wound on the outer surface of the expandable support body, evenly against the inner wall of the pulmonary artery. Neuromapping steps: Electrical stimulation signals are output through the spiral ablation electrodes, and sympathetic nerve enrichment target points are determined based on the subject's heart rate response; Ablation steps: Ablation energy is output at the sympathetic nerve enrichment target point through the spiral ablation electrode to form a continuous circumferential ablation zone; Effect verification steps: After ablation is completed, an electrical stimulation signal is output again through the spiral ablation electrode, and the denervation effect is verified based on the heart rate change.
9. The pulmonary artery denervation ablation method according to claim 8, characterized in that, During the ablation step, the temperature signals of multiple temperature sensing elements distributed along the spiral ablation electrode are acquired in real time. When the temperature detected by any of the temperature sensing elements exceeds a preset threshold, the output power of the ablation energy is automatically reduced or cut off. Preferably, in the effect verification step, if the heart rate change is greater than a preset threshold, it is determined that denervation is insufficient, and the ablation step and the effect verification step are repeated until the heart rate change is lower than the preset threshold.
10. A pulmonary artery denervation ablation system, comprising an ablation energy source, characterized in that, Also includes: Pulmonary artery denervation ablation catheter as described in any one of claims 1-7; An electrical stimulation generator is electrically connected to the spiral ablation electrode of the ablation catheter, and the electrical stimulation generator outputs an electrical stimulation signal through the spiral ablation electrode; A pressure transducer is fixedly connected to the proximal interface of the pressure transmission channel of the ablation catheter, and the pressure transducer converts the fluid pressure transmitted by the pressure transmission channel into a pressure signal output. The control input terminal of the ablation energy source is electrically connected to the spiral ablation electrode of the ablation catheter and the signal output terminal of the distributed temperature sensing array of the ablation catheter, respectively. The ablation energy source adjusts the output power of the ablation energy according to the temperature signal output by the distributed temperature sensing array.