Hepatic artery radiofrequency ablation method and ablation catheter

Abstract

The invention discloses a hepatic artery radiofrequency ablation method and ablation catheter. The ablation method comprises the steps that a target puncture point is positioned, and a radial artery puncture channel and an interventional ablation environment are established; guiding an ablation catheter to enter a target treatment point corresponding to the target artery branch; adjusting the end shape of the ablation section tube; the ablation catheter comprises an ablation section, a conveying section, a connecting section and a signal section. The catheter is inserted through a vascular intracavity path, penetrates into the hepatic artery or a near-end branch of the hepatic artery, targets autonomic nerves around the hepatic artery to carry out temperature control type radiofrequency ablation, and has the advantages of accurate positioning, safe control, uniformity of energy release and tissue adaptability; by adjusting the fitting posture of the spiral structure of the ablation section and adapting to the characteristic parameters such as the curvature direction, the tortuosity and the opening angle of the hepatic artery, it is ensured that the metal electrode can be effectively fitted with the tube wall to transmit radio frequency energy, meanwhile, the punching rate is reduced, liver parenchyma puncture injury is avoided, and meanwhile systemic intervention such as blood pressure regulation and metabolic function regulation is achieved.

Description

Technical Field

[0001] This invention relates to the field of medical catheter technology, and in particular to a hepatic artery radiofrequency ablation catheter and ablation method. Background Technology

[0002] Radiofrequency ablation is a minimally invasive interventional treatment technique. A specially designed metal electrode catheter is inserted through the skin into the lesion site (such as the heart, liver, or thyroid gland). The high-frequency current generates heat, causing coagulative necrosis of the local diseased tissue, thus achieving the therapeutic goal. This procedure has advantages such as minimal trauma, rapid recovery, and few complications, and is widely used in the treatment of various diseases, including arrhythmias, tumors, and uterine fibroids, especially in the field of refractory hypertension. Renal artery radiofrequency ablation is a minimally invasive interventional treatment technique for refractory hypertension. It uses a catheter to precisely target radiofrequency energy to the sympathetic nerves surrounding the renal artery, selectively destroying overactive nerve fibers with thermal energy. This reduces the excessive regulation of the kidneys and systemic blood vessels by the sympathetic nervous system, significantly and persistently reducing refractory hypertension.

[0003] Current radiofrequency ablation systems are mostly based on needle-type ablation structures, which are not suitable for releasing energy via arterial catheters. For patients with refractory hypertension, if their hypertension is not primarily caused by renal sympathetic hyperactivity (such as uncontrolled secondary hypertension, such as primary aldosteronism, renal artery stenosis, etc.) or if they have severe renal artery anatomical abnormalities (such as severe renal artery stenosis or malformation), renal artery ablation surgery is not only difficult to perform safely, but may also aggravate kidney damage, thus delaying the timing of targeted treatment. In patients with liver disease and metabolic syndrome, liver disease often leads to coagulation dysfunction (such as insufficient synthesis of coagulation factors in patients with cirrhosis), making the surgical puncture site prone to bleeding, significantly increasing the risk of complications. At the same time, fat accumulation around the renal artery can also easily interfere with catheter operation and energy delivery, reducing the effectiveness of the surgery. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a hepatic artery radiofrequency ablation catheter and ablation method.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a method for radiofrequency ablation of the hepatic artery, used to control the radiofrequency ablation catheter of the hepatic artery as described in the first aspect, the ablation method comprising:

[0006] S100, based on the hepatic artery interventional path, locates the target puncture point and establishes the radial artery puncture pathway and interventional ablation environment;

[0007] S200, insert a guiding catheter into the hepatic artery, and perform digital subtraction angiography to determine the location of the target branch;

[0008] S300: Guide the ablation catheter into the target treatment point corresponding to the target arterial branch, then withdraw the guide wire and release the metal electrode;

[0009] S400 determines the adhesion posture of the metal electrode based on the target blood vessel route and adjusts the shape of the end of the ablation segment tube.

[0010] In some embodiments, S100 includes:

[0011] S110, determine the first puncture distance based on the hepatic artery path, and locate the target puncture point;

[0012] S120, insert the first diameter antispasmodic sheath to establish radial artery puncture access;

[0013] S130, inject antispasmodic coagulation agent to establish an interventional ablation environment.

[0014] In some embodiments, S200 includes:

[0015] S210, a second diameter guiding catheter is inserted selectively into the celiac trunk and enters the main hepatic artery trunk in a reverse arch position;

[0016] S220, inject contrast agent to perform digital subtraction angiography, and determine the location of the target branch based on the course of the main branches of the hepatic artery.

[0017] In some embodiments, S300 includes:

[0018] S310, the guide wire guides the ablation catheter along the guide tube into the target arterial branch;

[0019] S320, guided by a fluoroscopic instrument, inserted into the target treatment point corresponding to the main hepatic artery;

[0020] S330, retract the guide wire and release the metal electrode.

[0021] In some embodiments, S400 includes:

[0022] S410A, determining the metal electrode bonding posture based on the curvature of the hepatic artery;

[0023] S420A, adjust the shape of the ablation tube end, rotate the ablation tube to adjust the metal electrode contact posture.

[0024] In some embodiments, S400 further includes:

[0025] S410B, determining the metal electrode bonding posture based on the hepatic artery tortuosity;

[0026] S420B, adjust the shape of the ablation tube end, rotate the ablation tube to adjust the metal electrode contact posture.

[0027] In some embodiments, S400 further includes:

[0028] S410C, determining the metal electrode contact posture based on the hepatic artery opening;

[0029] S420C, adjust the shape of the ablation tube end, rotate the ablation tube to adjust the metal electrode contact posture.

[0030] In some embodiments, S400 further includes:

[0031] S410D, determining the metal electrode bonding posture based on hepatic artery wall thickness;

[0032] S420D, adjust the shape of the ablation tube end, rotate the ablation tube to adjust the metal electrode contact posture.

[0033] Secondly, the present invention also provides a hepatic artery radiofrequency ablation catheter, comprising: an ablation segment for carrying a metal electrode, wherein the metal electrode is attached to the catheter wall to release radiofrequency energy through morphological switching;

[0034] The delivery section provides rigid support and delivers the ablation section and metal electrode to the preset ablation site by adapting to the tube wall size.

[0035] The connecting section is used to provide stress support and prevents bending at the connection point by connecting the ablation section and the delivery section.

[0036] The signal segment is used to connect the metal electrode to the external energy generator, transmitting radio frequency energy and feedback parameter signals through wires.

[0037] In some embodiments, the outer diameter of the ablation segment is no greater than 2 mm, the length of the ablation segment is 20-40 mm, and the bending radius of the ablation segment is no less than 2 cm.

[0038] The present invention has the following beneficial effects:

[0039] 1. This invention is aimed at patients with refractory hypertension and liver disease with metabolic syndrome who cannot undergo renal artery ablation. It uses an endovascular approach to insert a cannula into the hepatic artery or its proximal branches, and targets the autonomic nerves around the hepatic artery (such as hepatic sympathetic nerve fibers and celiac ganglion) for temperature-controlled radiofrequency ablation. It has precise positioning, safe control, uniform energy release and tissue compatibility.

[0040] 2. This invention adjusts the fit of the spiral structure of the ablation segment to match the curvature direction, tortuosity, opening angle and other characteristic parameters of the hepatic artery. This ensures that the metal electrode can effectively fit the vessel wall to transmit radiofrequency energy, thereby reducing the perforation rate and avoiding liver parenchymal puncture damage. At the same time, it achieves systemic interventions such as blood pressure regulation and metabolic function regulation. Attached Figure Description

[0041] Figure 1 A schematic diagram of the human blood vessels;

[0042] Figure 2 for Figure 1 The vascular network of the mesonephric and hepatic arteries Figure 1 ;

[0043] Figure 3 for Figure 1 The vascular network of the mesonephric and hepatic arteries Figure 2 ;

[0044] Figure 4 This is a schematic diagram of the hepatic artery radiofrequency ablation catheter proposed in this invention;

[0045] Figure 5 This is a flowchart illustrating the ablation method proposed in this invention. Figure 1 ;

[0046] Figure 6 This is a flowchart illustrating the ablation method proposed in this invention. Figure 2 ;

[0047] Figure 7 This is a flowchart illustrating the ablation method proposed in this invention. Figure 3 ;

[0048] Figure 8 This is a flowchart illustrating the ablation method proposed in this invention. Figure 4 ;

[0049] Figure 9 This is a flowchart illustrating the ablation method proposed in this invention. Figure 5 .

[0050] Legend:

[0051] 1. Ablation section; 2. Transport section; 3. Connecting section; 4. Signal section. Detailed Implementation

[0052] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0053] This application provides a hepatic artery radiofrequency ablation method and ablation catheter, addressing the problem that current radiofrequency systems are mostly based on needle-type ablation structures, which are unsuitable for energy release via arterial catheter pathways. For patients with refractory hypertension and liver disease accompanied by metabolic syndrome, the risks of renal artery radiofrequency ablation far outweigh the potential benefits. This application, however, uses an endovascular approach to insert a catheter into the hepatic artery or its proximal branches, targeting the autonomic nerves surrounding the hepatic artery for temperature-controlled radiofrequency ablation. This provides precise positioning, safe control, uniform energy release, and tissue adaptability. By adjusting the fit of the spiral structure of the ablation segment to match the curvature, tortuosity, and opening angle of the hepatic artery, it ensures that the metal electrode can effectively adhere to the catheter wall to deliver radiofrequency energy, thereby reducing the perforation rate and avoiding liver parenchymal puncture damage. Simultaneously, it achieves systemic interventions such as blood pressure regulation and metabolic function modulation.

[0054] Patients with refractory hypertension and liver disease with metabolic syndrome are not suitable candidates for renal artery radiofrequency ablation, mainly due to surgical risks, treatment effectiveness, and the patient's underlying condition.

[0055] like Figures 1-3 As shown, for patients with refractory hypertension, if their hypertension is not primarily caused by renal sympathetic hyperactivity (e.g., uncontrolled secondary hypertension, such as primary aldosteronism, renal artery stenosis, etc.), renal artery ablation is unlikely to be effective and may even delay targeted treatment. Furthermore, if the patient has severe renal artery anatomical abnormalities (e.g., severe renal artery stenosis, malformation) or end-stage renal disease, the surgery is not only difficult to perform safely but may also worsen kidney damage, with risks far outweighing benefits. In patients with liver disease and metabolic syndrome, liver disease often leads to coagulation disorders (e.g., insufficient synthesis of clotting factors in patients with cirrhosis), making the surgical puncture site prone to bleeding and significantly increasing the risk of complications. Simultaneously, obesity and insulin resistance associated with metabolic syndrome may lead to fat accumulation around the renal artery, interfering with catheter manipulation and energy transfer, reducing surgical effectiveness. Moreover, these patients are generally in poor condition, and liver dysfunction may affect postoperative recovery. The thermal effect of radiofrequency ablation may also increase the metabolic burden on the liver, further damaging liver function, resulting in a significant decrease in overall surgical tolerance and safety.

[0056] Understandably, the curvature and tortuosity of the hepatic artery path are significantly higher than those of the renal artery: the hepatic artery path naturally has multiple large-angle bends, including the large angle at the junction of the subclavian artery and the brachiocephalic trunk / aortic arch, the nearly 90-degree acute forward angle between the descending aorta and the celiac trunk, and the branch angles of the bifurcation of the common hepatic artery within the celiac trunk. Moreover, the overall path is longer. In elderly patients, the tortuosity, calcification, or aneurysm of the aorta, brachiocephalic trunk, and subclavian artery along the way will further increase the difficulty of the operation, resulting in significant loss of catheter support transmission. Therefore, the hepatic artery ablation catheter needs to have stronger support performance. On the other hand, the renal artery path is relatively straight. The main difficulty is the angle of the renal artery opening (especially the acute angle of the right renal artery). The descending aorta segment is shorter, and there are fewer large-angle bends to overcome (mainly the descending aorta). The impact of the tortuosity of the aorta and supra-aortic vessels is smaller due to the shorter path.

[0057] Furthermore, the location and angle of the target vessel opening further complicate the hepatic artery manipulation: the celiac trunk (Celiac The hepatic artery (CTA) is located high on the anterior wall of the abdominal aorta (usually at the level of the T12-L1 vertebral bodies), opening anterosuperiorly and forming an acute angle (close to 90 degrees or less) with the direction of aortic blood flow. The catheter must make a sharp upward turn to enter the celiac trunk from the descending aorta. After entering, it must pass through the angled common hepatic artery and proper hepatic artery (the bifurcation angle of the common hepatic artery, etc.), requiring extremely high precision in catheter turning and shaping ability. The renal artery is located low on the lateral wall of the abdominal aorta (usually at the level of the L1-L2 vertebral bodies). The opening of the right renal artery is usually higher (slightly higher than the left renal artery), forming a small acute angle (close to a right angle) with the aorta. After entering, the main trunk is relatively straight, but choosing the opening of the right renal artery requires slight looping or the use of a catheter with a specific shape to increase directionality, so entering the hepatic artery is more difficult than entering the renal artery. The opening of the left renal artery is slightly lower, forming an obtuse angle with the aorta, with a shorter path and a slight downward inclination, and is usually easier to enter than the right renal artery.

[0058] Please refer to the following examples for details:

[0059] Reference Figures 4-9 The present invention provides an embodiment of a hepatic artery radiofrequency ablation catheter, the specific structure of which includes: an ablation section 1 for carrying a metal electrode, a delivery section 2 for providing rigid support, a connection section 3 for providing stress support, and a signal section 4 for connecting the metal electrode to an external energy generator.

[0060] The ablation segment 1 is connected to the distal end of the delivery segment 2, and the metal electrode is brought into contact with the tube wall to release radio frequency energy through shape switching; the proximal end of the delivery segment 2 is connected to the distal end of the connection segment 3, and the ablation segment 1 and the metal electrode are delivered to the preset ablation site by adapting to the tube wall size; the proximal end of the connection segment 3 is connected to the distal end of the signal segment 4, and the connection of the ablation segment 1 and the delivery segment 2 is used to prevent the connection part from bending; the signal segment 4 transmits radio frequency energy and feedback parameter signals through wires.

[0061] It should be noted that the ablation section 1 and the delivery section 2 can be integrated or separate, with consistent internal structure and material composition.

[0062] Exemplarily, the metal electrode is a continuous metal electrode or a grouped metal electrode made of tightly wound metal electrode wires, which is made by tightly winding the metal electrode wires onto the ablation section 1 using a winding machine or manually. The metal electrode wires are made of metals or alloys with good biocompatibility and high stability (such as platinum group metals, gold, etc.), and in this embodiment, a platinum-iridium alloy is used. Each group of metal electrodes in the grouped metal electrodes is welded to a group of wires, which increases the length on the ablation section 1 compared to other forms of metal electrodes, thereby improving the ablation effect. Each group of metal electrodes can be connected to each other (relatively releasing energy) or be independent of each other (each group releases energy individually), allowing for flexible control of energy transfer according to surgical needs. To ensure that the metal electrodes are firmly installed in the ablation section 1 and to reduce damage to the blood vessel wall, adhesives (such as UV-curable adhesives, epoxy resin adhesives, or mixtures thereof) can be used to bond and fix the two ends of the metal electrode wires. Such adhesives have medical-grade biocompatibility and adhesion to both metal alloys and polymer materials; alternatively, a heat-shrinkable insulating layer can be used to bond and fix the two ends of the metal electrode wires to the ablation section 1.

[0063] Furthermore, the metal electrodes are welded to 1-8 sets of wires, which are used to transmit and regulate energy and provide feedback on temperature and impedance. The wires are located inside the insulation layer of ablation section 1, extending from the outermost layer of ablation section 1 and welded to the metal electrodes. They then extend within the insulation layer of ablation section 1 and the delivery section 2, finally being installed in connection section 3. The welding of the metal electrode wires to the wires can be done with solder (the solder joints are covered by the insulation layer) or with gold or silver (the solder joints can be exposed or covered by the insulation layer). Connection section 3 and the connecting cable to the external energy generator are integrated, so the wires also connect to external energy devices such as radio frequency devices. Correspondingly, the external energy generator can produce radio frequency, thermal, electromagnetic, ultrasonic, microwave, and light energy. When the metal electrodes are close to the target nerve site, energy is released and applied to that site to achieve regulation. For example, ablation can be achieved by transferring heat to raise the temperature of the target nerve fiber to 45°C or higher. Modulation can also be achieved by applying energy fields such as electromagnetic energy, radio frequency, or ultrasound. Among these, pulsed radio frequency electric fields or pulsed thermal energy are preferred because they can facilitate higher heat levels, longer durations, and more controllable treatment. The metal electrodes need to be electrically connected to the energy generating device; the connection method (such as a plug-and-play interface) is existing technology and will not be elaborated here.

[0064] Metal electrodes can also be used to apply an energy field to the target nerve fiber, which can include electromagnetic energy, radio frequency, ultrasound (including high-intensity focused ultrasound), microwaves, and light energy (including lasers, infrared, and near-infrared). For example, heat-induced neuromodulation can be achieved by delivering pulsed or continuous thermal energy fields to the target nerve fiber. A preferred energy method is a pulsed radio frequency electric field or other types of pulsed thermal energy. Pulsed radio frequency electric fields or other types of pulsed thermal energy can facilitate greater heat levels, longer total duration, and / or better controlled intravascular renal neuromodulation therapy. Regardless of the energy method used to modulate the nerve, when the user uses the renal artery radiofrequency ablation catheter of this embodiment, the metal electrode needs to be electrically connected to the device that generates the energy (e.g., a radiofrequency device) or the device that enables the metal electrode itself to generate the energy. These devices and the connection between the metal electrode and these devices are prior art well known to those skilled in the art (e.g., interfaces for connecting these devices are provided in the device of the present invention, enabling plug-and-play functionality), and will not be described in detail here.

[0065] It should be explained in detail that the ablation segment 1 has a first form and a second form. In the first form, the supporting component is adapted to move within the blood vessel; in the second form, the metal electrode is positioned to deliver radiofrequency energy to the target ablation site. Specifically, the outer diameter of the ablation segment 1 is no greater than 2 mm, the length of the ablation segment 1 is 20-40 mm, and the bending radius of the ablation segment 1 is no less than 2 cm; the elastic modulus of the ablation segment 1 is 0.08-0.12 GPa to accommodate thin-walled hepatic artery branches; the radial support of the ablation segment 1 is 0.1-0.3 N, thereby reducing the risk of perforation.

[0066] For example, the first morphology of the ablation segment 1 is linear or nearly linear (it can be elongated, fibrous, or filamentous), with a preferably circular or nearly circular cross-section. The widest point is smaller than the inner diameter of the blood vessel to ensure that the metal electrode does not damage the vessel wall when moving within the blood vessel. The inner diameter of a human renal artery is generally 4–7 mm, so the maximum radial dimension of the ablation segment 1 is no greater than 4 mm (preferably 1–2 mm), balancing ease of movement, rigidity, and minimal invasiveness. This morphology may also allow for some curvature or wavy curvature, and the cross-section can be of other shapes, as long as the surface is smooth, facilitates movement within the blood vessel, and does not damage the vessel wall.

[0067] The second form of ablation segment 1 includes a spiral or near-spiral shape, with its widest radial section being larger than the first form, allowing the metal electrode to approach or contact the vessel wall to adhere to the target nerve; it can also take other near-spiral shapes (such as a smooth, irregularly curved shape), as long as the metal electrode can contact the vessel wall. The second form may also include straight or near-straight sections, i.e., both sides of the spiral section are straight sections, with the front straight section improving the ablation effect and appearance, and the rear straight section meeting the structural requirements of the catheter itself.

[0068] The cavity of ablation section 1 is equipped with a pull wire for controlling its shape changes. The distal end of the pull wire is fixed to the distal inner wall of ablation section 1 by a resistance welding machine, allowing control of ablation section 1 to switch between a first and a second shape: when the pull wire is tightened, ablation section 1 is subjected to axial compressive force and is in the second shape; when the pull wire is loosened, ablation section 1 is in the first shape. The proximal end of the pull wire is connected to the interior of connecting section 3, and the operator can tighten or loosen the pull wire by pushing the control component.

[0069] For example, the ablation segment 1 of the radiofrequency ablation catheter is a tubular structure containing a cavity, and its metal tube layer is divided into a first segment, a second segment, a third segment, a fourth segment, and a fifth segment from the distal end to the proximal end, with corresponding first to fourth groups of cutting grooves:

[0070] (1) When the pull line is relaxed (without axial extrusion force), due to the elastic recovery characteristics of the alloy, each section of the metal tube layer remains straight, so that the first, second, third, fourth and fifth sections are in a continuous straight line first shape. The overall outer diameter is adapted to the inner diameter of the blood vessel, the surface is smooth, and it can move smoothly in the blood vessel without damaging the tube wall.

[0071] (2) When the wire is tightened (axial compressive force is applied), the first segment, due to the small spacing of the first group of cutting grooves and the short circumferential extension length, has high structural rigidity, maintains a straight shape and is parallel to the catheter axis, ensuring distal stability; the third segment, due to the smallest spacing of the third group of cutting grooves and the highest deformation sensitivity, changes from a straight shape to a spiral shape under the action of axial force, so that the metal electrode fits the vessel wall; the second and fourth segments, due to the larger spacing of the cutting grooves than the third group, have flexible transition capabilities, achieving smooth connection between the first and third segments and between the third and fifth segments respectively (without sudden bends), avoiding stress concentration; at this time, the ablation segment 1 presents a spiral second shape, with the metal electrode close to the target nerve, which can release radiofrequency energy to achieve ablation;

[0072] (3) When the axial compressive force is removed (the cable is loosened), the superelasticity of the alloy allows the second, third and fourth segments to return to their straight shape, and the whole structure returns to the first shape, which facilitates the removal of the catheter from the blood vessel.

[0073] Reference Figures 5-9 The present invention also provides an embodiment of a hepatic artery radiofrequency ablation method, used to control the hepatic artery radiofrequency ablation catheter as described in the above embodiment, the ablation method comprising:

[0074] S100, based on the hepatic artery interventional path, locates the target puncture point and establishes the radial artery puncture pathway and interventional ablation environment;

[0075] S200, insert a guiding catheter into the hepatic artery, and perform digital subtraction angiography to determine the location of the target branch;

[0076] S300: Guide the ablation catheter into the target treatment point corresponding to the target arterial branch, then withdraw the guide wire and release the metal electrode;

[0077] S400 determines the metal electrode's fit posture based on the target blood vessel's path and adjusts the end shape of the ablation segment 1 tube.

[0078] Please continue reading. Figure 6 In this embodiment, step S100 includes:

[0079] S110, determine the first puncture distance based on the hepatic artery path, and locate the target puncture point;

[0080] S120, insert the first diameter antispasmodic sheath to establish radial artery puncture access;

[0081] S130, inject antispasmodic coagulation agent to establish an interventional ablation environment.

[0082] For example, considering the high position of the celiac trunk (usually at the T12-L1 vertebral level) and its acute angle with the aorta, the first puncture distance from the radial styloid process to the target hepatic artery branch is determined. A first-diameter antispasmodic sheath is then inserted to establish a radial artery puncture pathway. In this embodiment, the target puncture point can be located 3 cm proximal to the radial styloid process, avoiding the wrist flexion area. This reduces path resistance caused by wrist movement during catheter advancement, ensuring stable advancement over long distances. Based on the thin walls and fine branches of the hepatic artery, a 6F antispasmodic sheath is inserted to establish a radial artery puncture pathway, providing rigid support for subsequent catheter delivery and preventing catheter bending during long-distance advancement. Then, an antispasmodic coagulation agent containing nitroglycerin, verapamil, and heparin is injected. Nitroglycerin and verapamil can relieve the vasospasm that easily occurs in the hepatic artery, while heparin can reduce the risk of thrombosis during long-distance procedures, thereby establishing a safe and stable interventional ablation environment and meeting the preoperative preparation requirements for hepatic artery radiofrequency ablation.

[0083] Please continue reading. Figure 7 In this embodiment, step S200 includes:

[0084] S210, a second diameter guiding catheter is inserted selectively into the celiac trunk and enters the main hepatic artery trunk in a reverse arch position;

[0085] S220, inject contrast agent to perform digital subtraction angiography, and determine the location of the target branch based on the course of the main branches of the hepatic artery.

[0086] For example, considering the near 90-degree forward acute angle between the descending aorta and the celiac trunk along the hepatic artery pathway, a second-diameter guiding catheter with strong shaping and support capabilities is selected, which shares the same support logic as the renal artery catheter but is adapted to the stronger support requirements of the hepatic artery. This allows for selective insertion into the celiac trunk in a reverse-bow posture (adapting to the upward and forward opening angle of the celiac trunk), thereby precisely entering the main hepatic artery trunk. This overcomes the core difficulty of the radial approach, where the catheter needs to make a sharp upward turn to enter the celiac trunk. In this embodiment, a 5F Simmons or Cobra guiding catheter can be used. The loop design of the mmons catheter allows for precise entry into the acute angle of the celiac trunk via reverse push from behind the aortic arch, while the curved tip of the Cobra catheter is suitable for grasping the arterial opening. Both can handle the large angle requirements of the hepatic artery (the renal artery opening angle is gentler, requiring less shaping of the guiding catheter). Subsequently, contrast agent is injected for digital subtraction angiography (DSA), which clearly shows the course of the main hepatic artery and its branches such as the common hepatic artery and proper hepatic artery. Based on this, the location of the target branch is determined, avoiding the catheter from entering a non-treatment branch, so that the subsequent ablation segment 1 can be delivered to the target area.

[0087] Please continue reading. Figure 8 In this embodiment, step S300 includes:

[0088] S310, the guide wire guides the ablation catheter along the guide tube into the target arterial branch;

[0089] S320, guided by a fluoroscopic instrument, inserted into the target treatment point corresponding to the main hepatic artery;

[0090] S330, retract the guide wire and release the metal electrode.

[0091] For example, due to the complex angles along the hepatic artery path, such as the 90-degree acute angle between the descending aorta and the celiac trunk, and the bifurcation of the common hepatic artery, and because elderly patients often have tortuosity and calcification in the aorta and brachiocephalic trunk, resulting in significant loss of support force transmission, it is necessary to guide the ablation segment 1 slowly into the target arterial branch along the already inserted guide catheter under the guidance of a guidewire. The guidewire pre-establishes a channel through the tortuous segment to provide support for the ablation catheter, while the rigidity of the delivery segment 2 of the ablation catheter (adapted to the stronger support requirements of the hepatic artery) ensures its smooth passage through difficult areas such as the celiac trunk. Subsequently, under the guidance of a fluoroscopic instrument (e.g., DSA equipment), the ablation segment 1 is slowly inserted into the target arterial branch. Guided by real-time imaging analysis, the catheter is precisely inserted into the target treatment point of the main hepatic artery based on the angiographic images of the main hepatic artery and its branches. This avoids misdirection into non-treatment areas due to the complexity of the hepatic artery branches (such as the variable course of the proper hepatic artery). During this process, the thin-walled characteristics of the hepatic artery must be taken into account to control the pushing force to prevent vascular damage. Then, the guide wire is withdrawn to release the restraint on ablation segment 1. Subsequently, by tightening the pull wire, ablation segment 1 is released from a straight shape (first form) to a spiral shape (second form), so that the metal electrode adheres to the vessel wall, preparing for the subsequent release of radiofrequency energy. Fine-tuning can also be used to ensure that the metal electrode is fully adhered to the target nerve area.

[0092] Please continue reading. Figure 9 In this embodiment, step S400 includes:

[0093] S410A, determining the metal electrode bonding posture based on the curvature of the hepatic artery;

[0094] S420A, adjust the shape of the end of the ablation section 1 tube, and rotate the ablation section 1 tube to adjust the metal electrode's contact posture.

[0095] For example, based on the acute angle curvature of the hepatic artery (e.g., the 90° forward angle between the celiac trunk and the descending aorta), the starting point of the spiral bend of the metal electrode segment needs to be adjusted by twisting. In this embodiment, the third segment (spiral segment) and the second segment (transition segment) are smoothly connected by the difference in the spacing of the cutting grooves. When the end of the ablation segment 1 is twisted: if the curvature is to the left (e.g., a branch of the left hepatic artery), the counterclockwise twist can advance the left starting point of the spiral segment through the flexibility of the second cutting groove, so as to fit the left acute angle wall; if the curvature is to the right (e.g., a branch of the right hepatic artery), the clockwise twist can advance the right starting point of the spiral segment through the deformation of the second cutting groove, so as to fit the right acute angle.

[0096] Furthermore, based on the curvature of the hepatic artery (e.g., the natural curvature of the proper hepatic artery), the radius of the spiral needs to be finely adjusted. In this embodiment, the diameter and pitch of the third spiral segment can be controlled by the density of the cutting grooves (the third group of cutting grooves has the smallest spacing and the highest deformation sensitivity). When the end of the ablation segment 1 is twisted: clockwise twisting can compress the third cutting groove and reduce the spiral diameter (suitable for liver branches with smaller diameters, such as the right hepatic artery with a diameter of 2-3 mm); counterclockwise twisting stretches the third cutting groove and increases the spiral diameter, suitable for the main liver trunk with a larger diameter (e.g., the common hepatic artery with a diameter of 4-5 mm).

[0097] Please continue reading. Figure 9 In this embodiment, step S400 further includes:

[0098] S410B, determining the metal electrode bonding posture based on the hepatic artery tortuosity;

[0099] S420B, adjust the shape of the end of the ablation section 1 tube, rotate the ablation section 1 tube to adjust the metal electrode's contact posture.

[0100] For example, for mild tortuosity (torsion angle <30°, such as mild aortic tortuosity in elderly patients), the metal electrode segment needs to be twisted slightly to make the metal electrode fit against the vessel wall. In this embodiment, the elasticity of the alloy allows the cutting groove to deform slightly. When the end of the ablation segment 1 is twisted: clockwise twisting allows the flexibility of the fourth cutting groove (transition segment) to slightly adjust the distal end of the spiral segment to the right, fitting against the tortuous right side wall; counterclockwise twisting allows the deformation of the fourth cutting groove to slightly adjust the distal end of the spiral segment to the left, adapting to the tortuous left side wall (avoiding local suspension of the metal electrode due to tortuosity and ensuring uniform energy release).

[0101] Furthermore, for severe tortuosity (torsion angle > 60°, such as tortuosity of the brachiocephalic trunk or aortic arch), it is necessary to adjust the overall direction of the spiral segment by significantly twisting the metal electrode segment. In this embodiment, the third segment has the highest cutting groove density (strongest deformation sensitivity). When the end of the ablation segment 1 is twisted: clockwise twisting can cause the third segment cutting groove to deform densely along the right side, and the spiral shape as a whole conforms to the tortuous path to the right; counterclockwise twisting can cause the third segment cutting groove to deform along the left side, and the spiral shape conforms to the tortuous blood vessel to the left, avoiding excessive twisting that could lead to catheter breakage.

[0102] Please continue reading. Figure 9 In this embodiment, step S400 further includes:

[0103] S410C, determining the metal electrode contact posture based on the hepatic artery opening;

[0104] S420C, adjust the shape of the end of the ablation section 1 tube, and rotate the ablation section 1 tube to adjust the metal electrode's contact posture.

[0105] For example, based on the celiac trunk opening anterosuperiorly at a high position (located at the T12-L1 level, forming an acute angle with the aorta anterosuperiorly), the direction of the straight portion of the electrode segment needs to be adjusted by twisting. In this embodiment, the first segment, keeping it straight, can serve as a rigid guide segment. When the end of the ablation segment 1 is twisted: clockwise twisting can make the front end of the first segment (straight segment) slightly upward, aligning it with the opening of the celiac trunk anterosuperiorly (avoiding the tip touching the posterior wall of the aorta); if the opening is biased to the left, counterclockwise twisting will cause the front end of the first segment to shift to the left, adapting to the celiac trunk opening that is biased to the left.

[0106] Furthermore, based on the bifurcation angle of the hepatic artery branches (e.g., the common hepatic artery branches into the left and right hepatic arteries, with bifurcation angles typically between 30-60°), the alignment of the helical segment and the branch opening needs to be adjusted by twisting. In this embodiment, the distance between the cutting grooves of the first segment (straight segment) and the second segment (transition segment) ensures a rigid connection. When the end of the ablation segment 1 is twisted: if the branch opening faces to the right (e.g., the right hepatic artery), clockwise twisting can cause the second segment to deflect the helical segment to the right, aligning the central axis of the electrode segment with the branch opening; if the branch opening faces to the left (e.g., the left hepatic artery), counterclockwise twisting, through the flexibility of the second segment, aligns the helical segment with the branch opening to the left, preventing the electrode edge from contacting the vessel wall at the bifurcation point and reducing the risk of perforation.

[0107] Please continue reading. Figure 9 In this embodiment, step S400 further includes:

[0108] S410D, determining the metal electrode bonding posture based on hepatic artery wall thickness;

[0109] S420D, adjust the shape of the end of the ablation section 1 tube, rotate the ablation section 1 tube to adjust the metal electrode's contact posture.

[0110] For example, to avoid excessive local pressure on the electrode segment (hepatic artery wall is thin), the adjustment range needs to be determined by the electrode winding density. In this embodiment, when the end of the ablation segment 1 tube is twisted: if the electrode is a continuous electrode (tightly wound), a small twist (±10°) can achieve fit through the small displacement of adjacent turns, avoiding excessive twisting that would cause excessive local pressure. If the electrode is a grouped electrode (intergroup spacing 1-15mm), a larger twist (±15-20°) can be used to align the target group electrode with the vessel wall. The intergroup gap can buffer the pressure and ensure that the electrode does not slip during twisting.

[0111] Furthermore, to ensure uniform contact of the electrode throughout its entire length (e.g., tortuous hepatic arteries can easily lead to local suspension), the number of spiral turns needs to be adjusted by twisting. In this embodiment, when the end of the ablation segment 1 is twisted: clockwise twisting can concentrate the number of spiral turns towards the distal end (e.g., 1.5 turns become 1 turn), adapting to short tortuous areas; counterclockwise twisting can expand the number of spiral turns towards the proximal end (e.g., 1 turn becomes 1.5 turns), covering long tortuous areas, ensuring that each turn of the electrode is in contact with the vessel wall, and that energy is released uniformly.

[0112] Through the above technical solution, this application targets patients with refractory hypertension and liver disease with metabolic syndrome who cannot undergo renal artery ablation. It employs an endovascular approach, inserting a cannula into the hepatic artery or its proximal branches, and performing temperature-controlled radiofrequency ablation targeting the autonomic nerves surrounding the hepatic artery (such as hepatic sympathetic nerve fibers and celiac ganglion). The helical structure of ablation segment 1 ensures safe control and uniform energy release, and optimizes tissue compatibility for the thin-walled characteristics of the hepatic artery. Simultaneously, by adjusting the fit of the helical structure of ablation segment 1 to match the curvature, tortuosity, and opening angle of the hepatic artery, it ensures effective adhesion of the metal electrode to the vessel wall for radiofrequency energy delivery while controlling radial support force to reduce perforation rate and avoid liver parenchymal puncture damage. Ultimately, it achieves systemic interventions such as blood pressure regulation and metabolic function modulation.

[0113] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for radiofrequency ablation of the hepatic artery, characterized in that, The ablation method includes: S100, based on the hepatic artery interventional path, locates the target puncture point and establishes the radial artery puncture pathway and interventional ablation environment; S200, insert a guiding catheter into the hepatic artery, and perform digital subtraction angiography to determine the location of the target branch; S300: Guide the ablation catheter into the target treatment point corresponding to the target arterial branch, then withdraw the guide wire and release the metal electrode; S400 determines the adhesion posture of the metal electrode based on the target blood vessel route and adjusts the shape of the end of the ablation segment tube.

2. The hepatic artery radiofrequency ablation method according to claim 1, characterized in that, S100 includes: S110, determine the first puncture distance based on the hepatic artery path, and locate the target puncture point; S120, insert the first diameter antispasmodic sheath to establish radial artery puncture access; S130, inject antispasmodic coagulation agent to establish an interventional ablation environment.

3. The hepatic artery radiofrequency ablation method according to claim 1, characterized in that, S200 includes: S210, a second diameter guiding catheter is inserted selectively into the celiac trunk and enters the main hepatic artery trunk in a reverse arch position; S220, inject contrast agent to perform digital subtraction angiography, and determine the location of the target branch based on the course of the main branches of the hepatic artery.

4. The hepatic artery radiofrequency ablation method according to claim 1, characterized in that, The S300 includes: S310, the guide wire guides the ablation catheter along the guide tube into the target arterial branch; S320, guided by a fluoroscopic instrument, inserted into the target treatment point corresponding to the main hepatic artery; S330, retract the guide wire and release the metal electrode.

5. The hepatic artery radiofrequency ablation method according to claim 1, characterized in that, The S400 includes: S410A, determining the metal electrode bonding posture based on the curvature of the hepatic artery; S420A, adjust the shape of the ablation tube end, rotate the ablation tube to adjust the metal electrode contact posture.

6. The hepatic artery radiofrequency ablation method according to claim 1, characterized in that, The S400 also includes: S410B, determining the metal electrode bonding posture based on the hepatic artery tortuosity; S420B, adjust the shape of the ablation tube end, rotate the ablation tube to adjust the metal electrode contact posture.

7. The hepatic artery radiofrequency ablation method according to claim 1, characterized in that, The S400 also includes: S410C, determining the metal electrode contact posture based on the hepatic artery opening; S420C, adjust the shape of the ablation tube end, rotate the ablation tube to adjust the metal electrode contact posture.

8. The hepatic artery radiofrequency ablation method according to claim 1, characterized in that, The S400 also includes: S410D, determining the metal electrode bonding posture based on hepatic artery wall thickness; S420D, adjust the shape of the ablation tube end, rotate the ablation tube to adjust the metal electrode contact posture.

9. A hepatic artery radiofrequency ablation catheter, characterized in that, include: The ablation section is used to support the metal electrode, and the metal electrode is made to adhere to the tube wall to release radio frequency energy through morphological switching. The delivery section provides rigid support and delivers the ablation section and metal electrode to the preset ablation site by adapting to the tube wall size. The connecting section is used to provide stress support and prevents bending at the connection point by connecting the ablation section and the delivery section. The signal segment is used to connect the metal electrode to the external energy generator, transmitting radio frequency energy and feedback parameter signals through wires.

10. The hepatic artery radiofrequency ablation catheter according to claim 9, characterized in that, The outer diameter of the ablation segment is no greater than 2mm, the length of the ablation segment is 20-40mm, and the bending radius of the ablation segment is no less than 2cm.

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