An electrode catheter for transcatheter septal branch radiofrequency ablation in hypertrophic obstructive cardiomyopathy

Abstract

The application belongs to the technical field of medical electrode catheter, and particularly discloses a kind of electrode catheter for trans-catheter septal branch radiofrequency ablation for hypertrophic obstructive cardiomyopathy, which comprises a catheter main body with a multi-layer composite structure, and an ablation electrode group is arranged at the head end of the catheter main body, and the ablation electrode group is connected to a plug arranged near the tail end of the catheter main body through a wire arranged in the catheter main body; the catheter main body comprises, from inside to outside, a polymer inner layer, a metal reinforcing layer, a polymer outer layer and a hydrophilic coating; the ablation electrode group comprises at least two annular ablation electrodes arranged at a preset interval along the axial direction of the catheter main body; and the wire is embedded in the pipe wall structure of the catheter main body.

Description

Technical Field

[0001] This invention belongs to the field of medical electrode catheter technology, specifically relating to an electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy. Background Technology

[0002] Hypertrophic obstructive cardiomyopathy (HOCM) is a hereditary myocardial disease characterized by left ventricular outflow tract (LVOT) obstruction. It can lead to severe dyspnea, syncope, and significantly increase the risk of sudden cardiac death (SCD). Currently, invasive treatments for HOCM mainly fall into three categories: (a) Surgical ventricular septal myocardectomy (SM, i.e., Morrow procedure): SM is the gold standard for the surgical treatment of HOCM. Its advantage lies in the most thorough obstruction relief, which can simultaneously correct mitral regurgitation, papillary muscle abnormalities and other associated cardiac structural lesions, and can significantly reduce the risk of SCD. However, this procedure is highly invasive, requiring open-chest surgery and the establishment of cardiopulmonary bypass. The perioperative mortality rate can reach more than 5% in non-specialized centers. Patients have a long hospital stay, usually 1-2 weeks, and full recovery takes 3-6 months. In addition, there are potential complications such as ventricular septal perforation, aortic valve injury, arrhythmia, and pericardial effusion during the operation, and the operation requires extremely high surgical skills, making it difficult to promote in primary hospitals.

[0003] (II) Percutaneous transseptal ablation with alcohol (PTSMA): PTSMA is currently the preferred minimally invasive treatment method, requiring no open-chest surgery or cardiopulmonary bypass. However, its effectiveness in relieving obstruction is not as good as SM, and 10%-20% of patients still have significant symptoms after the procedure. The 5-year re-intervention rate is about 15%, which is about nine times that of SM. Due to the injection of anhydrous alcohol during the procedure, there is a risk of alcohol spillage into other branches of the left anterior descending artery. Moreover, the spatial range of chemical ablation is not precisely controlled, which can easily induce serious complications such as third-degree atrioventricular block and ventricular fibrillation. Furthermore, about 10%-15% of patients cannot undergo the procedure due to unsuitable coronary anatomy, which means there is no suitable septal branch artery. The permanent pacemaker implantation rate due to atrioventricular block is about 10%.

[0004] (III) Percutaneous ventricular septal radiofrequency ablation (including the Liwen procedure, etc.): Emerging percutaneous radiofrequency ablation techniques such as the Liwen procedure have further improved the minimally invasive nature of the procedure, allowing for real-time and precise control of the ablation range and making it more widely applicable. However, this technique places extremely high demands on the operator's skills and the guidance of imaging techniques such as ultrasound, making it a high-barrier learning experience for doctors. This limits the promotion of percutaneous radiofrequency ablation technology in primary hospitals and general medical centers.

[0005] In summary, the three existing invasive treatment methods for HOCM all have limitations to varying degrees: surgical procedures are highly invasive and have many complications; alcohol ablation has an uncontrollable range and depends on specific coronary anatomy; and radiofrequency ablation is too dependent on the operator's skills. Therefore, there is an urgent need for a new type of treatment device that has a low operating threshold, a precise and controllable ablation range, high safety, and is easy to promote. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides an electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solution: An electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy includes a multi-layered composite catheter body. An ablation electrode assembly is located at the tip of the catheter body. The ablation electrode assembly is connected to a plug located near the tail end of the catheter body via a wire disposed within the catheter body. The catheter body comprises, from the inside out, a polymer inner layer, a metal reinforcing layer, a polymer outer layer, and a hydrophilic coating. The ablation electrode assembly includes at least two annular ablation electrodes arranged at a predetermined interval along the axial direction of the catheter body. The wire is embedded within the catheter wall structure and is used to electrically connect each annular ablation electrode to the plug. The plug is used to connect to an external radiofrequency ablation device to transmit ablation energy and receive ablation parameter control signals.

[0008] According to the above-mentioned electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy, preferably, the catheter body is a coaxial guidewire (OTW) structure, the outer diameter of the catheter body is ≤2F, the working length is 135cm, and the catheter body is provided with a hollow inner cavity for the guidewire to pass through.

[0009] According to the above-mentioned electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy, preferably, the annular ablation electrode is a metal electrode, and the annular ablation electrodes are arranged at equal intervals of 10 mm within a 4 cm range along the tip of the catheter body; the ablation electrode can serve as both the energy output electrode for radiofrequency ablation and the intracardiac potential mapping electrode, used to monitor the His bundle potential in real time, so as to prevent damage to the His bundle during the ablation process that could lead to severe atrioventricular block.

[0010] According to the electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy, preferably, the annular ablation electrode is used for intracardiac potential mapping, for recording and outputting His bundle potential signals, so as to monitor the effects of radiofrequency ablation in real time, prevent severe atrioventricular block, and improve safety.

[0011] According to the electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy, preferably, the plug is a standard medical multi-pole connector, which connects to the energy output channel and electrophysiological recording channel of the radiofrequency ablation device, and displays the ablation energy, temperature, impedance and potential signals in real time through the visualization interface of the radiofrequency ablation device.

[0012] According to the electrode catheter for transcatheter radiofrequency ablation of septal branch in hypertrophic obstructive cardiomyopathy, preferably, the hydrophilic coating is used to reduce the external friction coefficient of the catheter body under the wetted state of physiological saline, which is beneficial to the advancement and retraction of the catheter body in the septal branch artery.

[0013] According to the electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy, preferably, the inner polymer layer is made of polytetrafluoroethylene (PTFE) or polyimide; the metal reinforcing layer is made of stainless steel braided mesh or spiral metal wire; the outer polymer layer is made of polyamide (PA) or polyether block amide (PEBA); and the hydrophilic coating includes a hydrophilic polymer coating to reduce the coefficient of friction between the catheter and the vessel wall and guidewire.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The electrode catheter of the present invention can guide the ablation catheter through the ventricular septal branch artery to accurately ablate the hypertrophic myocardium causing obstruction and improve the ablation effect; the ring ablation electrode can map the His bundle potential, thereby avoiding serious atrioventricular block and improving the safety of ablation; the energy of the ring ablation electrode is displayed in real time through the visualization interface of the radiofrequency ablation instrument, which facilitates quantitative and localized ablation of myocardium and improves the safety and effect of ablation; the electrode catheter of the present invention can be operated by traditional catheter technology, and any operator with a foundation in coronary intervention technology can easily implement it, which is highly operable and conducive to learning and promotion.

[0015] (2) The operation threshold of the present invention is low and easy to promote: The electrode catheter of the present invention is compatible with the existing coronary intervention operation technology system. It can be implemented using 6F JL or EBU guiding catheter and PTCA guidewire. Operators with basic coronary intervention technology can master it without special ultrasound guidance technology training, which can greatly reduce the learning curve and facilitate its application in more centers.

[0016] (3) The ablation of the present invention is precise and effective: The present invention guides the ablation catheter through the coronary guidewire to the target septal branch artery, which can achieve precise positioning and ablation of the hypertrophic myocardium that causes obstruction. The ablation range is determined by the radiofrequency energy parameters that are quantified and controlled in real time, which can avoid the inherent defect of uncontrollable diffusion of chemical substances during alcohol ablation.

[0017] (4) The present invention has high safety and can monitor the conduction system in real time: the ring ablation electrode integrated on the catheter body can record the His bundle potential in real time. Once the ablation operation affects the conduction system, the operator can immediately terminate the ablation or adjust the position of the catheter body, which can effectively prevent the occurrence of complications such as severe atrioventricular block and the need for implantation of a permanent pacemaker.

[0018] (5) The present invention can realize visualized, timed, quantitative and localized ablation: the energy output of the ring ablation electrode is displayed in real time through the visualization interface of the radiofrequency ablation instrument, which can realize the dual precise control of timed, quantitative and localized ablation of myocardium, and ensure surgical safety while improving the ablation effect.

[0019] (6) This invention does not rely on specific coronary anatomy and has a wider range of indications: Compared with PTSMA, this invention has no special requirements for the anatomy of septal branch arteries and has a wider range of applications.

[0020] (7) The present invention can solve the technical problems of high difficulty in existing treatment operations, uncontrollable ablation range, and many complications, and can achieve safe, accurate and repeatable invasive ablation effect of HOCM. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the longitudinal section structure of the catheter body in this invention; Figure 3 This is a schematic diagram of the cross-sectional structure of the catheter body in this invention; Figure 4 This is a schematic diagram of the annular ablation electrode in this invention; Figure 5 This is a schematic diagram illustrating the use of the present invention.

[0022] The components include: 1. Handle; 2. Catheter body; 3. Ring ablation electrode; 4. Guide wire; 5. Hollow inner cavity; 6. Polymer inner layer; 7. Metal reinforcing layer; 8. Polymer outer layer; 9. Hydrophilic coating; and 10. Lead wire. Detailed Implementation

[0023] The present invention will be further illustrated by specific embodiments below, but this does not limit the scope of the invention. Example 1

[0024] An electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy, such as... Figure 1-5As shown, the catheter body 2 includes a multi-layered composite structure. An ablation electrode assembly is located at the tip of the catheter body 2. The ablation electrode assembly is connected to a plug located near the tail end of the catheter body 2 via a wire 10 disposed within the catheter body 2. The catheter body 2 comprises, from the inside out, a polymer inner layer 6, a metal reinforcing layer 7, a polymer outer layer 8, and a hydrophilic coating 9. The ablation electrode assembly includes three annular ablation electrodes 3 arranged at a predetermined spacing along the axial direction of the catheter body 2. The wire 10 is embedded within the wall structure of the catheter body 2 and is used to electrically connect each annular ablation electrode 3 to the plug. The plug is used to connect to an external radiofrequency ablation device to transmit ablation energy and receive ablation parameter control signals.

[0025] The catheter body 2 is a coaxial guidewire (OTW) structure with an outer diameter of 1.9F and a working length of 135cm. It is suitable for coronary intervention via the femoral or radial artery. The catheter body 2 has a hollow lumen 5 for the guidewire 4 to pass through. The hollow lumen 5 is compatible with 0.014-inch PTCA guidewire 4.

[0026] The annular ablation electrode 3 is a metal electrode, and the annular ablation electrode 3 is arranged at equal intervals of 10 mm within a 4 cm range from the tip of the catheter body 2.

[0027] The ring ablation electrode 3 is used for intracardiac potential mapping, recording and outputting His bundle potential signals to monitor the effects of radiofrequency ablation in real time, prevent severe atrioventricular block, and improve safety.

[0028] The plug is a standard medical multi-pole connector, which connects to both the energy output channel and the electrophysiological recording channel of the radiofrequency ablation device, and displays the ablation energy, temperature, impedance, and potential signals in real time through the visualization interface of the radiofrequency ablation device.

[0029] The hydrophilic coating 9 is used to reduce the external friction coefficient of the catheter body 2 when it is moistened by physiological saline, which is beneficial for the advancement and retraction of the catheter body 2 in the septal branch artery.

[0030] The inner polymer layer 6 is made of polytetrafluoroethylene (PTFE) or polyimide, and its smooth inner wall reduces the friction of the guidewire 4. The metal reinforcing layer 7 is made of stainless steel braided mesh or spiral metal wire, which provides radial support and torque transmission, and also facilitates catheter visualization. The outer polymer layer 8 is made of polyamide (PA) or polyether block amide (PEBA), which balances flexibility and pushability. The hydrophilic coating 9 includes a hydrophilic polymer coating, which is used to reduce the coefficient of friction between the catheter and the vessel wall and the guidewire 4. The coefficient of friction is significantly reduced in a wet state, which facilitates the smooth passage of the catheter body 2 through the septal branch artery.

[0031] A method for performing transcatheter radiofrequency ablation of the septal branch of hypertrophic obstructive cardiomyopathy using an electrode catheter includes the following steps: S1. Coronary angiography: Identifying the target septal branch artery through coronary angiography.

[0032] Preoperative preparation includes comprehensive evaluation of echocardiography, coronary CT, and coronary angiography to clarify the anatomical morphology of the target septal branch artery and its correspondence with the hypertrophic ventricular septum; standard electrocardiogram and pressure monitoring are established in the cardiac catheterization laboratory, and a temporary pacemaker is prepared.

[0033] S2. Electrode catheter insertion: via the femoral or radial artery approach, using a 6F JL or EBU guide catheter body 2 to reach the ostium of the left coronary artery, and then inserting the PTCA guidewire 4 to the target septal branch artery.

[0034] Vascular approach: via femoral or radial artery puncture, insertion of an arterial sheath, systemic heparinization (ACT>250s); guiding catheter placement: a 6F JL4.0 or EBU3.5 guiding electrode catheter is selected according to the patient's ascending aortic anatomy and advanced to the ostium of the left coronary artery under X-ray guidance for selective coronary angiography to identify the target septal branch artery; guidewire 4 is advanced into the target septal branch: a 0.014-inch PTCA guidewire 4 with a soft tip is advanced into the target septal branch artery to the distal end under X-ray guidance.

[0035] S3. Placement of ablation catheter: Push the electrode catheter along the PTCA guidewire 4 to the predetermined target ablation site of the target septal branch artery.

[0036] Along the PTCA guidewire 4 that has been positioned, the handle 1 is used to push the catheter body 2 into the target septal branch artery along the PTCA guidewire 4 inside the hollow lumen 5. The position of the circular ablation electrode 3 is confirmed by X-ray fluoroscopy combined with the position of the circular ablation electrode 3, so that the circular ablation electrode 3 reaches the septal branch segment corresponding to the target hypertrophic myocardium.

[0037] S4. Potential monitoring: The His bundle potential is measured in real time by the annular ablation electrode 3 to confirm that the position of the annular ablation electrode 3 maintains a safe distance from the conduction system.

[0038] Potential mapping and safety confirmation: Connect the radiofrequency ablation device, start the intracardiac potential recording function, map the intracardiac electrogram at each ablation electrode, and confirm that the His bundle potential is not recorded or is recorded at a safe distance to ensure ablation safety.

[0039] S5. Radiofrequency ablation: Connect the radiofrequency ablation device via the plug, set the ablation energy and time parameters, and perform quantitative, timed, and localized radiofrequency ablation on the target myocardium to degenerate and necrose the hypertrophic myocardium around the target septal branch artery, thereby eliminating the obstruction.

[0040] Set ablation parameters: It is recommended to set the initial power loop to 10-20W, the upper limit of temperature to 55-60℃, and the time to 60-120s. Perform fixed-point radiofrequency ablation under the monitoring of the visual interface. Adjust the parameters in real time according to impedance changes and temperature feedback. If necessary, adopt the near-segment → far-segment approach to achieve step ablation.

[0041] S6. Assessment: After ablation, the pressure gradient change of the left ventricular outflow tract is assessed by echocardiography or pressure guidewire to confirm the obstruction relief effect.

[0042] Immediate assessment: After ablation, measure the LVOT pressure difference with a pressure guidewire or perform echocardiography to assess the relief of the obstruction; if there is significant residual obstruction, the ablation time can be appropriately extended or the electrode position adjusted before ablation can be performed again, provided that safety is confirmed.

[0043] S7. End of procedure: After confirming that the ablation effect is satisfactory, remove the catheter body 2, PTCA guidewire 4 and guiding catheter in sequence, apply local pressure to stop bleeding, and send the patient to the intensive care unit for continuous electrocardiographic monitoring. Example 2

[0044] An electrode catheter for transcatheter radiofrequency ablation of the septal branch in hypertrophic obstructive cardiomyopathy differs from that in Example 1 in that the ablation electrode assembly includes three annular metal ablation electrodes; the outer diameter of the catheter body 2 is 1.9F; and the working length of the catheter body 2 is 130cm. Example 3

[0045] An electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy differs from Example 1 in that the outer diameter of the catheter body is ≤2F and the working length is 100-140cm.

[0046] The above description is only a preferred embodiment of the present invention, but is not limited to the above examples. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy, characterized in that, The catheter body includes a multi-layered composite structure. The head end of the catheter body is provided with an ablation electrode assembly, which is connected to a plug located near the tail end of the catheter body via a wire disposed within the catheter body. The catheter body comprises, from the inside out, a polymer inner layer, a metal reinforcing layer, a polymer outer layer, and a hydrophilic coating. The ablation electrode assembly includes at least two annular ablation electrodes arranged at a predetermined interval along the axial direction of the catheter body. The wire is embedded within the wall structure of the catheter body.

2. The electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy according to claim 1, characterized in that, The catheter body is a coaxial guidewire structure with an outer diameter ≤2F and a working length of 135cm. The catheter body has a hollow inner cavity for the guidewire to pass through.

3. The electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy according to claim 1, characterized in that, The annular ablation electrode is a metal electrode, and the annular ablation electrodes are arranged at equal intervals of 10 mm within a 4 cm range along the tip of the catheter body.

4. The electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy according to claim 1, characterized in that, The ring-shaped ablation electrode is used for intracardiac potential mapping.

5. The electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy according to claim 1, characterized in that, The plug is a standard medical multi-pole connector, which connects to both the energy output channel and the electrophysiological recording channel of the radiofrequency ablation device, and displays the ablation energy, temperature, impedance, and potential signals in real time through the visualization interface of the radiofrequency ablation device.

6. The electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy according to claim 1, characterized in that, The hydrophilic coating is used to reduce the external friction coefficient of the catheter body when it is moistened by physiological saline.

7. The electrode catheter for transcatheter septal radiofrequency ablation of hypertrophic obstructive cardiomyopathy according to claim 1, characterized in that, The inner polymer layer is made of polytetrafluoroethylene or polyimide; the metal reinforcing layer is made of stainless steel woven mesh or spiral metal wire; the outer polymer layer is made of polyamide or polyether block amide; and the hydrophilic coating includes a hydrophilic polymer coating.

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