Vascular intervention type garland-like ablation electrode catheter

Abstract

The invention provides a blood vessel intervention type garland-like ablation electrode catheter, and relates to the technical field of medical instruments, the blood vessel intervention type garland-like ablation electrode catheter comprises a catheter body, an injection catheter fixing assembly is mounted on the catheter body, a garland is mounted on the catheter body, a magnetic anchoring assembly is mounted at one end, away from the catheter body, of the garland, and an energy transmission interface is mounted at one end, away from the garland, of the catheter body; the energy transmission interface is electrically connected with the garland, the garland is composed of three groups of deployable garland units, each garland unit is composed of a supporting strip and a petal-shaped electrode slice, the supporting strip is connected with the petal-shaped electrode slice, a first microfluid channel is arranged on the inner side of the petal-shaped electrode slice, and a medicine injection hole is formed in the surface of the petal-shaped electrode slice; a blood vessel invaded by a tumor is used as a channel, the blood vessel intervention electrode catheter is used for replacing a traditional rigid electrode needle, meanwhile, through garland-shaped unfolding, displacement generated by vascular movement and ablation operation is reduced, an ablation area is effectively fixed, and tissue damage caused by invalid ablation and repeated ablation is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a vascular interventional wreath-shaped ablation electrode catheter. Background Art

[0002] Malignant tumors are a serious threat to human health and represent the most severe public health challenge facing the world. Liver, biliary tract, and pancreatic malignancies are the most common types of digestive system tumors. They often present insidiously, with subtle and atypical early symptoms, making diagnosis difficult. Most patients present in the advanced stages of the disease by the time they seek medical attention, missing the opportunity for radical surgery. Effective treatments are urgently needed.

[0003] Pulsed electric field (PEF) ablation is a non-thermal tumor ablation technique that applies an electric field to cells, causing perforation of the cell membrane, disrupting their homeostasis and leading to cell death. The treatment process does not cause thermal damage, is not affected by heat sink effects, and is not restricted by the surrounding anatomy of the tumor. This advantage holds significant therapeutic potential for digestive tract tumors with complex structures such as adjacent blood vessels and lumens, such as pancreatic cancer and intrahepatic bile duct carcinoma.

[0004] However, as PEF research and clinical application continue to deepen, its limitations are becoming increasingly apparent. Because PEF is a local ablative treatment, it still lags behind traditional surgical resection in terms of disease-free survival and recurrence rates. Furthermore, the complex microenvironment within tumor tissue leads to uneven electric field distribution, preventing the effective ablation field from fully covering the entire tumor tissue, ultimately resulting in incomplete ablation. Therefore, PEF often needs to be combined with other treatments to achieve more thorough tumor ablation. Combination therapy is key to improving efficacy and preventing tumor recurrence.

[0005] Whether used alone or in combination, current PEF treatments utilize rigid needle electrodes inserted into the tumor through open or percutaneous laparotomy. Examples include AngioDynamics' NanoKnife, Hangzhou Redi Biotechnology's AirEasy Steep Pulse Minimally Invasive Therapy System, Tianjin Yuanshan Medical Technology Co., Ltd.'s Steep Pulse Therapy Device, Sino Micro Medical Technology Co., Ltd.'s Nanosecond Knife, and Shanghai Redi Biotechnology Co., Ltd.'s Prostate Cancer Composite Steep Pulse Therapy Device. Tumor ablation using needle electrodes has drawbacks, such as significant trauma and a high risk of needle tract metastasis. Therefore, the present invention proposes a vascular interventional rosette-shaped ablation electrode catheter to address these existing challenges. Summary of the Invention

[0006] In view of the above problems, the purpose of the present invention is to propose a vascular interventional rosette-like ablation electrode catheter, which has the advantages of minimally invasive tumor ablation and can solve the problems existing in the prior art.

[0007] To achieve the purpose of the present invention, the present invention is implemented through the following technical solutions: a vascular interventional garland-like ablation electrode catheter, comprising a tube body, an injection catheter fixing assembly is installed on the tube body, and a garland is installed on the tube body, a magnetic anchoring assembly is installed on the end of the garland away from the tube body, an energy transmission interface is installed on the end of the tube body away from the garland, and the energy transmission interface is electrically connected to the garland, the garland is composed of three groups of expandable garland units, the garland unit is composed of a support bar and a petal-shaped electrode sheet, the support bar is connected to the petal-shaped electrode sheet, and the support bar is an axially penetrating hollow structure, one end of the support bar is hinged to the magnetic anchoring assembly, the inner side of the petal-shaped electrode sheet is provided with a first microfluidic channel, and the surface of the petal-shaped electrode sheet is provided with a drug injection hole, and the drug injection hole is connected to the first microfluidic channel.

[0008] A further improvement is that a micro temperature sensor is integrated on the petal-shaped electrode sheet, and the micro temperature sensor is electrically connected to the energy transmission interface.

[0009] A further improvement is that a micro impedance sensor is integrated on the petal-shaped electrode sheet, and the micro impedance sensor is electrically connected to the energy transmission interface.

[0010] A further improvement is that the tube body includes an outer catheter and an electrode catheter, an electrode catheter is provided on the inner side of the outer catheter, and a protective tube is provided on the outer side of the outer catheter, a metal claw cage is installed on the outer catheter through an electrode ring, the metal claw cage is connected to the wreath, one end of the electrode catheter is electrically connected to the energy transmission interface, and the other end of the electrode catheter is connected to the magnetic anchoring assembly.

[0011] A further improvement is that the magnetic anchoring assembly includes an insulating shell, a magnet unit is provided on the inner side of the insulating shell, and a magnetic fixing cap is installed at the end of the magnet unit, and the volume of the magnet unit does not exceed 30% of the total volume of the magnetic fixing cap.

[0012] A further improvement is that the magnetic fixing cap is integrated with an N-pole permanent magnet or an S-pole permanent magnet, and adopts a coupling structure of opposite-name magnetic poles to achieve cross-tumor anchoring.

[0013] A further improvement is that the petal-shaped electrode sheet is made of a shape memory alloy or a conductive polymer, the shape memory alloy is a nickel-titanium alloy, and the conductive polymer is a polypyrrole composite conductive material.

[0014] Further improvements are: the energy transmission interface is used to connect an external energy output device to transmit ablation energy to the garland, the ablation energy is pulsed electric field energy, and its pulse parameters are: voltage 100~3000V, pulse width 1μs~100μs, frequency 1~100Hz.

[0015] A further improvement is that the injection catheter fixing assembly includes a fixing seat, which is fixedly connected to the protective tube, and a drug injection tube is installed on the fixing seat, the inner cavity of the drug injection tube is connected to the first microfluidic channel, a threaded hole is provided on the inner side of the fixing seat, and a pipe connecting port is installed on the inner side of the threaded hole, and one end of the pipe connecting port is fixedly connected to the drug injection tube.

[0016] A further improvement is that the drug injection holes are distributed on the sides of the ablation area of ​​the petal-shaped electrode sheet.

[0017] The beneficial effects of the present invention are:

[0018] (1) The present invention uses the blood vessels invaded by the tumor as a path to place the electrode catheter into the tumor area. The electrode catheter adopts an upper and lower package layout, and is unfolded through a wreath-like structure to ensure that the tumor area is surrounded in space and a stable electric field is formed. By applying high-voltage pulse electricity, an electric field is formed between the electrode sheets, and the tumor tissue is effectively ablated. Since pulsed electric field ablation has a non-thermal effect, it causes minimal damage to the vascular stent structure. At the same time, after ablation, the electrode catheter is used to give the vascular inner wall protective agent to the ablation site, which can achieve the purpose of minimally invasive ablation of the tumor while protecting the vascular structure; and after entering the blood vessel, the wreath-like expansion and fixation are suitable for fixing the ablation area of ​​larger blood vessels to avoid ineffective ablation; or after ablation, the electrode catheter is used to give the ablation site an embolic agent for vascular embolization, which can achieve the combined treatment purpose of pulsed electric field ablation combined with tumor vascular embolization therapy.

[0019] (2) The present invention utilizes vascular interventional technology to place an electrode catheter through a blood vessel into the tumor site, eliminating the need for traditional surgical procedures such as tissue incision or direct insertion of a needle electrode, thereby avoiding trauma and the risk of needle tract metastasis. This feature enables minimally invasive treatment, reducing patient recovery time and postoperative complications. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a front view schematic diagram of the wreath of the present invention after it is unfolded.

[0021] Figure 2 It is a front view schematic diagram of the wreath of the present invention after contraction.

[0022] Figure 3 It is a schematic diagram of the present invention in working state.

[0023] Figure 4It is a front view structural diagram of the connection between the fixing seat and the protective tube of the present invention.

[0024] Among them: 1. Outer catheter; 2. Electrode catheter; 3. Electrode ring; 4. Protective tube; 5. Magnetic anchoring assembly; 6. Petal-shaped electrode sheet; 601. First petal-shaped electrode sheet; 602. Second petal-shaped electrode sheet; 603. Third petal-shaped electrode sheet; 7. Support bar; 8. Metal claw cage; 9. Micro temperature sensor; 10. Syringe; 11. Energy transmission interface; 12. Fixing seat; 13. Drug injection tube; 14. Pipeline connection port. DETAILED DESCRIPTION

[0025] In order to deepen the understanding of the present invention, the present invention will be further described in detail below with reference to the examples. The examples are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention.

[0026] Pulsed electric field (PEF) ablation technology involves applying a short, high-intensity electric field to tumor tissue, causing a transient rupture of the cell membrane (called electroporation), disrupting the cell's biomembrane stability, leading to leakage of cellular contents and cell death. PEF technology is unique in that it can ablate tumors without significant thermal effects, making it unaffected by heat sink effects and particularly suitable for treating tumors adjacent to vital organs or blood vessels.

[0027] A major limitation of PEF technology is that due to the complex microenvironment of tumor tissue, the electric field distribution within the tumor is often uneven. This can result in some areas of the tumor not being effectively affected by the electric field, leading to incomplete ablation. This uneven electric field distribution is often related to factors such as tumor morphology, tissue type, size, and anatomical location.

[0028] Most PEF treatment devices currently used in clinical practice use rigid needle electrodes for ablation, especially during open surgery or percutaneous insertion into the tumor. Although rigid needle electrodes can directly enter the tumor for treatment, this approach has some disadvantages:

[0029] Large trauma: When the needle electrode is inserted into the tumor, a hole needs to be made in the skin or body, which causes relatively large trauma.

[0030] Risk of needle tract metastasis: When the needle tract enters the tumor, it may cause cancer cells to spread through the needle tract to healthy tissues or other parts around the tumor, increasing the risk of tumor metastasis.

[0031] Unstable puncture site: Since the tumor may move with the patient's body position during the puncture process, the use of rigid needle electrodes may lead to unstable treatment position, thus affecting the treatment effect.

[0032] Therefore, according to Figures 1-4 As shown, this embodiment proposes a vascular interventional garland-like ablation electrode catheter, including a tube body, having a proximal end and a distal end, the proximal end being connected to an external operating handle, and the distal end extending to the target vascular area. The tube body includes an outer catheter 1 and an electrode catheter 2. Specifically, the inner side of the outer catheter 1 is provided with an electrode catheter 2, and the outer side of the outer catheter 1 is provided with a protective tube 4. A metal claw cage 8 is installed on the outer catheter 1 through an electrode ring 3. The metal claw cage 8 is connected to the garland. One end of the electrode catheter 2 is electrically connected to the energy transmission interface 11, and the other end of the electrode catheter 2 is connected to the magnetic anchoring assembly 5. Furthermore, the electrode catheter 2 includes an energy wire cavity (transmitting a pulsed electric field to the garland electrode), a second microfluidic channel (connecting to the drug injection hole) and a sensor signal line cavity (transmitting temperature data and impedance data). The electrode ring 3 is an annular mechanical interface fixed to the inner wall of the distal end of the outer catheter 1. A slide rail structure is provided on the inner side to engage with the metal claw cage 8 to achieve axial push-pull control of the wreath. The metal claw cage 8 is a mesh telescopic structure woven from shape memory alloy. The proximal end is fixed to the electrode ring 3, and the distal end is connected to the support bar 7. After the wreath is unfolded, the mesh structure of the metal claw cage 8 generates radial tension, which cooperates with the magnetic anchor component 5 to suppress the displacement caused by blood vessel pulsation.

[0033] An injection catheter fixing assembly is mounted on the tube body. The assembly includes a fixing base 12 made of medical-grade PEEK (polyetheretherketone). The fixing base 12 is fixedly connected to the protective tube 4 (bonded with a biocompatible adhesive, with a bonding area of ​​≥80%). A drug injection tube 13 is mounted on the fixing base 12. The drug injection tube 13 is a polytetrafluoroethylene (PTFE) hose with an outer diameter of ≤1.2 mm. The tube 13 extends through the fixing base 12 into the tube body. The lumen of the drug injection tube 13 is connected to the first microfluidic channel (one end of the drug injection tube 13 extends into the tube body). A threaded hole is provided on the inner side of the fixing base 12, and a pipe connection port 14 is mounted on the inner side of the threaded hole. One end of the pipe connection port 14 is fixedly connected to the drug injection tube 13 (the drug injection tube 13 is connected to the pipe connection port 14 via a Luer connector). A double-lip medical silicone sealing ring is embedded in the pipe connection port 14. The function of the injection catheter fixing assembly is to prevent the tube from folding during interventional procedures by pre-fixing and protecting it.

[0034] A garland is mounted on the tube body. The garland is composed of three groups of expandable garland units. When the garland units are expanded, they form a ring structure to surround the blood vessel-tumor interface. The garland units are composed of support bars 7 and petal-shaped electrode sheets 6, namely, a first petal-shaped electrode sheet 6, a second petal-shaped electrode sheet 6, and a third petal-shaped electrode sheet 6. Specifically, the petal-shaped electrode sheets 6 are constrained to expand to a maximum angle of 120°±5°, and the folded diameter is ≤2.0mm. The petal-shaped electrode sheets 6 are made of shape memory alloy or conductive polymer, wherein the shape memory alloy is nickel-titanium alloy and the conductive polymer is a polypyrrole composite conductive material. In this embodiment, shape memory alloy is used. The support bar 7 is connected to the petal-shaped electrode sheet 6, and the support bar 7 is an axially penetrating hollow structure. One end of the support bar 7 is hinged to the magnetic anchor assembly 5. A first microfluidic channel is provided on the inner side of the petal-shaped electrode sheet 6, and a drug injection hole is provided on the surface of the petal-shaped electrode sheet 6. The pore size is 0.1 to 0.5 mm. The drug injection hole is connected to the first microfluidic channel. The drug injection holes are distributed on the side of the ablation area of ​​the petal-shaped electrode sheet 6. Furthermore, the ablation area of ​​the petal-shaped electrode sheet 6 is covered with a porous insulating layer, and the drug injection holes penetrate the insulating layer and are exposed on the electrode surface, forming a drug diffusion window. Specifically, the drug injection tube 13 is connected to the injection pipe of the external syringe 10 through the injection catheter fixing assembly, and then the therapeutic agent is synchronously released to the tumor-vascular tissue junction area during the pulsed electric field ablation process.

[0035] A micro-temperature sensor 9 (thin-film NTC thermistor) is integrated into the petal-shaped electrode sheet 6 and embedded in the non-operating area of ​​the petal-shaped electrode sheet 6 (≥0.3 mm from the edge). The micro-temperature sensor 9 is electrically connected to the energy transmission interface 11 and is used to monitor temperature changes in the ablation area in real time, ensuring that the temperature does not exceed the set threshold during the ablation process, thereby avoiding overheating or damage to healthy tissue.

[0036] A micro-impedance sensor is integrated into the petal-shaped electrode sheet 6 and electrically connected to the energy transmission interface 11. The micro-impedance sensor is used to monitor changes in the resistance of tumor tissue. Impedance changes are related to factors such as tumor tissue density and tissue type. By monitoring these changes, the impedance sensor can help assess ablation efficacy and adjust treatment parameters in real time. In this embodiment, the micro-temperature sensor 9 and the micro-impedance sensor share a common line for signal transmission, so time-sharing multiplexing is used for data monitoring.

[0037] A magnetic anchoring assembly 5 is installed at the end of the wreath away from the tube body. The magnetic anchoring assembly 5 includes an insulating shell, a magnet unit is provided on the inner side of the insulating shell, and a magnetic fixing cap is installed at the end of the magnet unit. The volume of the magnet unit does not exceed 30% of the total volume of the magnetic fixing cap. The magnetic fixing cap is integrated with an N-pole permanent magnet or an S-pole permanent magnet, and adopts a polarity coupling structure to achieve cross-tumor anchoring. Specifically, the insulating shell is injection molded with medical-grade polyetheretherketone (PEEK) or zirconium oxide ceramic material, and its inner cavity is precisely embedded with a neodymium iron boron permanent magnet (grade N52) as a magnet unit. The volume of the magnet unit is strictly controlled to within 30% of the total volume of the magnetic fixing cap (tolerance ±2%) to ensure the focusing of the magnetic field. The end of the magnet unit is integrated with the magnetic fixing cap by laser welding, and the surface of the fixing cap is designed with a barb array (barb height 0.1 to 0.3 mm, inclination angle 45°) to enhance the instantaneous adhesion ability of the blood vessel wall.

[0038] like Figure 3 As shown, in this embodiment, two garland-shaped ablation electrode catheters 2 need to be inserted into the blood vessel, that is, this catheter needs to be deployed in coordination with another identical catheter. The specific difference is that when the magnetic fixing cap of this catheter is integrated with an N-pole permanent magnet, the magnetic fixing cap of the other catheter is integrated with an S-pole permanent magnet. When the two are inserted into the opposite sides of the tumor tissue through the blood vessels (with a spacing of 15 to 50 mm), they are distributed in an upper and lower package, and the opposite magnetic poles generate a magnetic attraction of ≥0.5T to achieve precise cross-tumor coupling. This magnetic attraction can suppress blood vessel pulsation and respiratory displacement (tissue deformation compensation amount ±1.5mm), so that the petal electrode can be stably attached to the blood vessel-tumor interface, and cooperate with the pulsed electric field output to form a continuous ablation zone, and the boundary matching accuracy reaches sub-millimeter level (±0.3mm).

[0039] An energy transmission interface 11 is installed at the end of the tube body away from the wreath (proximal end), and the energy transmission interface 11 is electrically connected to the wreath. The energy transmission interface 11 is used to connect an external energy output device to transmit ablation energy to the wreath. The ablation energy is pulsed electric field energy, and its pulse parameters are: voltage 100~3000V, pulse width 1μs~100μs, frequency 1~100Hz.

[0040] For tumors that invade multiple blood vessels, several pairs of wreath-like ablation electrode catheters 2 can be inserted into different invaded blood vessels to form a "surrounding" mode for the tumor, thereby forming an electric field between different wreath-like ablation electrode catheters 2, expanding the coverage of the tumor and improving the ablation effect.

[0041] After the ablation operation is completed, vascular protective agents are injected to protect the blood vessels in the ablation area, minimizing the damage of the pulsed electric field to the inner wall of the blood vessels and improving the safety and effectiveness of the treatment; or vascular embolic agents are injected from the drug delivery cavity to embolize the tumor-invaded blood vessels, achieving the treatment of pulsed electric field ablation combined with vascular embolization, and improving the effect of pulsed electric field treatment.

[0042] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above-described embodiments. The above-described embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and improvements may be made to the present invention without departing from the framework and scope of application of the present invention. Such changes and improvements are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A vascular interventional rosette-shaped ablation electrode catheter, comprising a tube body, characterized in that: The tube body is provided with an injection catheter fixing assembly, and a garland is provided on the tube body, a magnetic anchoring assembly (5) is provided on one end of the garland away from the tube body, an energy transmission interface (11) is provided on the one end of the tube body away from the garland, and the energy transmission interface (11) is electrically connected to the garland, the garland is composed of three groups of expandable garland units, the garland units are composed of a support bar (7) and a petal-shaped electrode sheet (6), the support bar (7) is connected to the petal-shaped electrode sheet (6), and the support bar (7) is an axially penetrating hollow structure, one end of the support bar (7) is hinged to the magnetic anchoring assembly (5), the inner side of the petal-shaped electrode sheet (6) is provided with a first microfluidic channel, and the surface of the petal-shaped electrode sheet (6) is provided with a drug injection hole, and the drug injection hole is connected to the first microfluidic channel.

2. The vascular interventional rosette-shaped ablation electrode catheter according to claim 1, characterized in that: A micro temperature sensor (9) is integrated on the petal-shaped electrode sheet (6), and the micro temperature sensor (9) is electrically connected to the energy transmission interface (11).

3. The vascular interventional rosette-shaped ablation electrode catheter according to claim 1, characterized in that: A micro impedance sensor is integrated on the petal-shaped electrode sheet (6), and the micro impedance sensor is electrically connected to the energy transmission interface (11).

4. The vascular interventional rosette-shaped ablation electrode catheter according to claim 1, characterized in that: The tube body comprises an outer catheter (1) and an electrode catheter (2); the electrode catheter (2) is provided on the inner side of the outer catheter (1), and a protective tube (4) is provided on the outer side of the outer catheter (1); a metal claw cage (8) is installed on the outer catheter (1) through an electrode ring (3); the metal claw cage (8) is connected to the wreath; one end of the electrode catheter (2) is electrically connected to an energy transmission interface (11), and the other end of the electrode catheter (2) is connected to a magnetic anchoring assembly (5).

5. The vascular interventional rosette-shaped ablation electrode catheter according to claim 1, characterized in that: The magnetic anchoring assembly (5) comprises an insulating shell, a magnet unit is provided on the inner side of the insulating shell, and a magnetic fixing cap is installed at the end of the magnet unit, and the volume of the magnet unit does not exceed 30% of the total volume of the magnetic fixing cap.

6. The vascular interventional rosette-shaped ablation electrode catheter according to claim 5, characterized in that: The magnetic fixing cap is integrated with an N-pole permanent magnet or an S-pole permanent magnet, and adopts a coupling structure of opposite-name magnetic poles to achieve cross-tumor anchoring.

7. The vascular interventional rosette-shaped ablation electrode catheter according to claim 1, characterized in that: The petal-shaped electrode sheet (6) is made of a shape memory alloy or a conductive polymer, the shape memory alloy is a nickel-titanium alloy, and the conductive polymer is a polypyrrole composite conductive material.

8. The vascular interventional rosette-shaped ablation electrode catheter according to claim 1, characterized in that: The energy transmission interface (11) is used to connect an external energy output device to transmit ablation energy to the garland. The ablation energy is pulsed electric field energy, and its pulse parameters are: voltage 100-3000V, pulse width 1μs-100μs, and frequency 1-100Hz.

9. The vascular interventional rosette-shaped ablation electrode catheter according to claim 1, characterized in that: The injection catheter fixing assembly comprises a fixing seat (12), the fixing seat (12) is fixedly connected to the protective tube (4), and a drug injection tube (13) is installed on the fixing seat (12), the inner cavity of the drug injection tube (13) is communicated with the first microfluidic channel, a threaded hole is provided on the inner side of the fixing seat (12), and a pipeline connecting port (14) is installed on the inner side of the threaded hole, and one end of the pipeline connecting port (14) is fixedly connected to the drug injection tube (13).

10. The vascular interventional rosette-shaped ablation electrode catheter according to claim 1, characterized in that: The drug injection holes are distributed on the sides of the ablation area of ​​the petal-shaped electrode sheet (6).

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