Shock wave electrode structure and shock wave balloon catheter

Abstract

Provided in the present invention are a shock wave electrode structure and a shock wave balloon catheter. The shock wave electrode structure comprises a first electrode and a second electrode spaced apart and extending in the same direction. The first electrode has a first distal end surface, and the second electrode has a second distal end surface. When the first distal end surface and the second distal end surface are located in a conductive liquid and a voltage is applied to the first electrode and the second electrode, a shock wave is generated only between the first distal end surface and the second distal end surface. The shock wave balloon catheter comprises the shock wave electrode structure. The shock wave electrode structure and the shock wave balloon catheter of the present application are tolerant of a higher applied voltage, produce stably a sufficient number of shock waves with stronger single shock wave energy, and possess sufficiently strong single shock wave energy and accumulated shock wave energy, thus achieving the treatment on sclerotic tissues at sites not able to or not suitable to receive dilation using solely the shockwave energy without the help of dilation to soften these sclerotic tissues and partially restore tissue functions.

Description

Shock wave electrode structure and shock wave balloon catheter

[0001] Related applications

[0002] This disclosure claims priority to Chinese patent application number CN 202410335049.6, filed with the Patent Office of China on March 22, 2024, entitled “Shock Wave Electrode Structure and Shock Wave Balloon Catheter,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to the technical field of interventional medical devices, and in particular to a shock wave electrode structure and a shock wave balloon catheter. Background Art

[0004] When a shock wave encounters a significant difference in acoustic impedance between two adjacent materials during propagation, a strong interaction occurs at the interface between the two. When the shock wave propagates from liquid or liquid-like soft tissue to solid tissue (such as calcified tissue in blood vessels), it interacts strongly with the solid tissue at the interface and continues to propagate through the liquid or liquid-like soft tissue medium, gradually attenuating. Within an appropriate energy range, the shock wave's damaging effects on soft tissue are negligible. The interactions between shock waves and solid tissue include compression, shearing, stretching, cavitation, and extrusion, which can loosen or create cracks in the solid tissue. For safety and controllability reasons, electrohydraulic shock waves are currently widely used in the medical field. The basic principle of electrohydraulic shock waves is to apply a high voltage (potential difference) to electrodes in a liquid medium (conductive liquid) with a certain conductivity, generating a transient discharge of high current within a few microseconds. During the discharge, a high-energy-density, high-temperature, high-pressure plasma region forms in the discharge channel, causing the discharge channel to expand rapidly and generating a pressure pulse in the liquid medium, known as a shock wave. In addition to generating shock waves, part of the electrical energy is converted into heat and light during the discharge process.

[0005] Current shock wave catheters are used to loosen or crack calcified tissue in coronary or peripheral blood vessels, allowing for expansion via balloon inflation, thereby alleviating vascular stenosis or facilitating subsequent treatment. Shock wave catheters are already commercially available, and their safety and effectiveness have been fully validated. However, existing shock wave balloon catheters are unable to treat sclerotic tissue (e.g., calcified tissue) in areas where expansion is impossible or inconvenient (e.g., the mitral and aortic valves). Summary of the Invention

[0006] In view of this, the present invention provides a shock wave electrode structure and a shock wave balloon catheter to achieve the purpose of using shock wave energy to treat hardened tissue in areas that cannot or are inconvenient to expand.

[0007] An embodiment of the present invention provides a shock wave electrode structure, comprising a first electrode and a second electrode, which are spaced apart and extend in the same direction; the first electrode has a first distal surface, and the second electrode has a second distal surface; when the first distal surface and the second distal surface are located in a conductive liquid and a voltage is applied to the first electrode and the second electrode, a shock wave can be generated only between the first distal surface and the second distal surface.

[0008] The present invention also provides a shock wave balloon catheter, comprising the above-mentioned shock wave electrode structure, a tube body, and an expansion element capable of being filled with a conductive liquid; the expansion element is sealedly connected to the distal end of the tube body, and the first distal end surface and the second distal end surface of the shock wave electrode structure are both located within the expansion element; when the expansion element is filled with conductive liquid and a voltage is applied to the first electrode and the second electrode of the shock wave electrode structure, a shock wave can be generated only between the first distal end surface and the second distal end surface.

[0009] Compared with the prior art, the beneficial effects that can be achieved by at least one of the above-mentioned technical solutions adopted in the embodiments of this specification include at least the following: the shock wave electrode of the present application can withstand a higher applied voltage, stably generate shock waves with a sufficient number of times and stronger single shock wave energy, and have sufficiently large single shock wave energy and cumulative shock wave energy, thereby achieving the purpose of treating hardened tissues in areas where expansion is impossible or inconvenient using only shock wave energy without the need for expansion, thereby softening these hardened tissues and restoring some tissue functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0011] FIG1 is a perspective schematic diagram of a first structure in a first embodiment of the present application;

[0012] FIG2 is a schematic axial projection diagram of the second structure in the first embodiment of the present application;

[0013] FIG3 is a schematic axial projection diagram of the third structure in the first embodiment of the present application;

[0014] FIG4 is a schematic axial projection diagram of the first structure in the second embodiment of the present application;

[0015] FIG5 is a schematic axial projection diagram of the second structure in the second embodiment of the present application;

[0016] FIG6 is a schematic axial projection diagram of the third structure in the second embodiment of the present application;

[0017] FIG7 is a schematic axial projection diagram of the fourth structure in the second embodiment of the present application;

[0018] FIG8 is a schematic axial projection diagram of the fifth structure in the second embodiment of the present application;

[0019] FIG9 is a theoretical schematic diagram of the energy change of a single shock wave of the structure shown in FIG8 ;

[0020] FIG10 is a schematic axial projection diagram of a structure of the third embodiment of the present application;

[0021] FIG11 is a theoretical schematic diagram of a single shock wave energy change of the structure shown in FIG10 ;

[0022] FIG12 is a schematic axial projection diagram of the first structure in the fourth embodiment of the present application;

[0023] FIG13 is a schematic axial projection diagram of the second structure in the fourth embodiment of the present application;

[0024] FIG14 is a schematic axial projection diagram of a structure of the fifth embodiment of the present application;

[0025] FIG15 is a perspective schematic diagram of a first structure in a first embodiment of the present application having an insulating portion;

[0026] FIG16 is a schematic axial projection diagram of the second structure in the first embodiment of the present application having an insulating portion;

[0027] FIG17 is a schematic axial projection diagram of the third structure of the first embodiment of the present application having an insulating portion;

[0028] FIG18 is a schematic axial projection diagram of the first structure in the second embodiment of the present application having an insulating portion;

[0029] FIG19 is a schematic axial projection diagram of a second structure in the second embodiment of the present application having an insulating portion;

[0030] FIG20 is a schematic axial projection diagram of the third structure in the second embodiment of the present application having an insulating portion;

[0031] FIG21 is a schematic axial projection diagram of a fourth structure in the second embodiment of the present application having an insulating portion;

[0032] FIG22 is a schematic axial projection diagram of the fifth structure in the second embodiment of the present application having an insulating portion;

[0033] FIG23 is a schematic axial projection diagram of a structure of the third embodiment of the present application having an insulating portion;

[0034] FIG24 is a schematic axial projection diagram of the first structure in the fourth embodiment of the present application having an insulating portion;

[0035] FIG25 is a schematic axial projection diagram of the second structure in the fourth embodiment of the present application having an insulating portion;

[0036] FIG26 is a schematic axial projection diagram of a structure of the fifth embodiment of the present application having an insulating portion;

[0037] FIG27 is a schematic structural diagram of a preferred embodiment of the present application;

[0038] FIG28 is a schematic diagram of the partial structure of the shock wave balloon catheter of the present application.

[0039] Reference numerals in the figure: 10, first electrode; 11, first distal surface; 1101, first segment of first distal surface; 1102, second segment of first distal surface; 1103, third segment of first distal surface; 20, second electrode; 21, second distal surface; 211, first sub-electrode segment; 212, second sub-electrode segment; 213, third sub-electrode segment; 2101, first segment of second distal surface; 2102, second segment of second distal surface; 2103, third segment of second distal surface; 2104, fourth segment of second distal surface; 30, expansion element; 40, insulating part; 41, distal surface; 50, fluid inlet cavity; 60, fluid discharge cavity; 70, insulating member; 80, tube body; 100, shock wave electrode structure. DETAILED DESCRIPTION

[0040] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0041] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the features in the following embodiments and embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of this application.

[0042] Because the shock wave balloon catheters of the prior art are only used to form cracks on the treated tissue of tubular structures (such as coronary arteries and peripheral blood vessels), the shock wave generating device is very easy to be close to the treated tissue, and the distance between the shock wave generating device and the hardened tissue of the lesion site is very close, so the utilization rate of the shock wave energy is relatively high. Therefore, the shock wave electrode structure of the prior art only needs to provide shock waves with fewer triggering times and lower single energy, that is, to obtain lower single shock wave energy and cumulative shock wave energy, in order to form cracks on the treated tissue of the blood vessel. However, even if the utilization rate of shock wave energy is higher in the treated tissue of tubular structures, higher single shock wave energy and cumulative shock wave energy are still helpful for the treatment of the treated tissue. However, a higher applied voltage means a faster electrode melting and ablation rate (during the discharge breakdown process). Because the existing shock wave electrode structure is constrained by its own design characteristics, when the shock wave electrode of the prior art is connected to a higher applied voltage, the electrode quickly melts and abslates, and the distal end of the shock wave electrode presents a concave structure. The material produced by the electrode melting and ablation accumulates in the concave structure, causing the shock wave electrode structure of the prior art to fail rapidly. Therefore, the shock wave electrode structure of the present application is intended to enable the electrode to withstand a sufficiently high applied voltage and form a sufficient number of discharge breakdowns through structural changes, thereby obtaining stable shock waves with sufficient frequency and sufficient single energy, and then obtaining sufficiently large single shock wave energy and cumulative shock wave energy, thereby achieving the purpose of using shock wave energy to treat hardened tissue in areas that cannot or are inconvenient to expand, and solving the problem that hardened tissue in lesions cannot be treated using the shock wave balloon catheter of the existing technology or cannot be treated using the shock wave balloon catheter of the existing technology in combination with an expansion device.

[0043] Based on the shock wave electrode structure of the present application, the inventors of the present application have found through a large number of shock wave energy test studies that, when other conditions remain unchanged, there is the following relationship between the discharge distance, the exposed area of ​​the electrode and the applied voltage and the energy of a single shock wave. Among them, the discharge distance refers to the electrical gap between the two electrodes (when the two electrodes are only insulated by air) or the creepage distance (when there is an insulator between the two electrodes that affects the electrical gap), the exposed area of ​​the electrode refers to the exposed area of ​​the electrode in the air (without insulation performance, used to generate shock waves), the single shock wave energy refers to the shock wave energy released by a single shock wave, and the cumulative shock wave energy refers to the total shock wave energy released during the entire discharge breakdown process of the shock wave electrode structure. The "discharge distance remains unchanged" here means that the electrode distance hardly changes during the entire breakdown process.

[0044] 1. The discharge distance and the exposed area of ​​the electrode remain unchanged: when the applied voltage is small, no shock wave is generated; when the applied voltage reaches the first value, the electrode begins to discharge and break down to form a shock wave; the applied voltage continues to increase, and the energy of a single shock wave increases with the increase in the applied voltage, but the increase in the energy of a single shock wave is not proportional to the increase in the applied voltage, and the increase in the energy of a single shock wave is small; when the applied voltage reaches the second value, the increase in the energy of a single shock wave is significantly reduced, but the duration of the discharge breakdown to form a shock wave is shortened. Here, the first value is defined as the minimum breakdown voltage, and the second value is defined as the maximum effective voltage;

[0045] 2. Only the exposed area of ​​the electrode remains unchanged: the greater the discharge distance, the greater the minimum breakdown voltage. At the same time, the energy of the single shock wave generated by the discharge breakdown is also greater; vice versa;

[0046] 3. The exposed area of ​​the electrode and the applied voltage remain unchanged: When the discharge distance is large, no shock wave is generated; the discharge distance gradually decreases until the electrode begins to discharge and break down to form a shock wave. The smaller the discharge distance, the smaller the energy of a single shock wave.

[0047] 4. When only the discharge distance remains unchanged, the smaller of the electrode exposed areas has an impact on the discharge breakdown of the electrode: as the smaller electrode exposed area increases, the minimum breakdown voltage of the electrode discharge breakdown increases; however, the effect of the smaller electrode exposed area on the minimum breakdown voltage is much smaller than the effect of the discharge distance on the minimum breakdown voltage;

[0048] 5. Discharge distance and applied voltage remain unchanged: When the applied voltage is greater than the minimum breakdown voltage and less than the maximum effective voltage, the larger the exposed area of ​​the smaller electrode, the longer the time it takes for the discharge breakdown to form a shock wave, and the greater the energy of a single shock wave, and vice versa;

[0049] 6. The energy of a single shock wave when the electrode with a smaller exposed area is the positive electrode is greater than the energy of a single shock wave when the electrode with a smaller exposed area is the negative electrode.

[0050] It can be seen from this that if one wants to achieve the purpose of using shock wave energy to treat hardened tissue in areas that cannot or are inconvenient to expand, it is necessary to obtain sufficiently large single shock wave energy and cumulative shock wave energy. Based on the above findings, it can be learned that this requires the electrode to be able to withstand a sufficiently high applied voltage and form a sufficient number of discharge breakdowns, so that a stable shock wave with a sufficient number of times and a sufficiently large single energy can be obtained during the multiple discharge breakdown processes.

[0051] As shown in Figures 1 to 27, an embodiment of the present invention provides a shock wave electrode structure 100, including a first electrode 10 and a second electrode 20 that are arranged at intervals and extend in the same direction; the first electrode 10 has a first distal surface 11, and the second electrode 20 has a second distal surface 21; when the first distal surface 11 and the second distal surface 21 are located in a conductive liquid and a voltage is applied to the first electrode 10 and the second electrode 20, a shock wave can be generated only between the first distal surface 11 and the second distal surface 21.

[0052] In this article, "distal end" refers to the end away from the operator, and "proximal end" refers to the end close to the operator. The shock wave electrode structure 100 of the present application generates a shock wave at the distal surface. The extension direction of the second electrode 20 is the same as the extension direction of the first electrode 10, which only means that the first electrode 10 and the second electrode 20 both extend between the proximal end and the distal end, and it is not necessary for the extension direction of the second electrode 20 to be parallel to the extension direction of the first electrode 10. The side surfaces of the first electrode 10 and the second electrode 20 in the extension direction are insulated from each other, and the insulation strength value is greater than the applied voltage value; the first distal surface 11 of the first electrode 10 and the second distal surface 21 of the second electrode 20 are non-insulated. When the first electrode 10 and the second electrode 20 are subjected to applied voltage, no discharge breakdown occurs on the side surfaces of the first electrode 10 and the second electrode 20 in the extension direction, and only the corresponding potential difference is generated between the first distal surface 11 and the second distal surface 21, and discharge breakdown generates a shock wave.

[0053] The following briefly describes the discharge breakdown process of the shock wave electrode structure 100 of the present application. The first distal surface 11 is a set of points A (including points A1, A2, ...An), and the second distal surface 21 is a set of points B (including points B1, B2, ...Bn). The first electrode 10 and the second electrode 20 are electrically connected to a high-voltage pulse power supply. A first potential difference is generated between the first electrode 10 and the second electrode 20. Discharge and breakdown occur between the two closest points A1 and B1 on the first distal surface 11 and the second distal surface 21. Electrical energy is rapidly converted into heat energy, forming a first shock wave. A1 and B1 undergo ablation and rapidly form a melt. The changes to the first distal surface 11 and the second distal surface 21 are as follows: 1) The first distal surface 11 is ablated at A1, and the second distal surface 21 is ablated at B1 to form a depression. At the location of this depression, the distance between the first distal surface 11 and the second distal surface 21 increases. 2) The conductivity of the melt formed by the ablation of A1 and B1 is much lower than that of the electrode itself. Therefore, it is difficult for the melt to discharge and break down to generate a shock wave, or the energy intensity of the shock wave generated by the breakdown discharge is insufficient to have a therapeutic effect. Therefore, when a second potential difference is generated between the first electrode 10 and the second electrode 20, if A2 and B2 are the two points closest to the first distal surface 11 and the second distal surface 21 at this time, discharge and breakdown will occur between A2 and B2, and the electrical energy will be quickly converted into heat energy to form a second shock wave, and so on. Therefore, by simultaneously increasing the ablation area of ​​the first distal surface 11 and the second distal surface 21, more shock waves can be triggered.

[0054] Therefore, the shock wave electrode structure 100 of the present application sets the location where the shock wave occurs at the distal surface, so that the first distal surface 11 of the first electrode 10 and the second distal surface 21 of the second electrode 20 can both be set as surface structures. The first distal surface 11 can be set as a plane or a curved surface, and the second distal surface 21 can be set as a plane or a curved surface; according to the target value of the single shock wave energy, the first distal surface 11 and the second distal surface 21 both have a suitable exposed area, that is, the first electrode 10 and the second electrode 20 can obtain a sufficiently large effective melting volume. From the above-mentioned discharge breakdown process of the shock wave electrode structure 100 of the present application, it can be seen that: 1) the larger effective melting volume allows a sufficiently far electrode distance to be set between the first distal end face 11 and the second distal end face 21, so that when a sufficiently high applied voltage is applied to the first electrode 10 and the second electrode 20, a shock wave with a stronger single shock wave energy is obtained during a single discharge breakdown process; and, 2) when a shock wave is generated under the same applied voltage, the larger effective melting volume allows the first distal end face 11 and the second distal end face 21 to stably withstand more times of melting and ablation, thereby having more shock waves triggered, and stably obtaining shock waves with a sufficient number of times and a sufficiently strong single shock wave energy. Therefore, the shock wave electrode structure 100 of the present application can withstand a sufficient number of sufficiently high applied voltages, and at a suitable electrode distance, obtain a sufficiently large single shock wave energy and cumulative shock wave energy, thereby achieving the purpose of using shock wave energy to treat hardened tissue in areas that cannot or are inconvenient to expand.

[0055] As a spherical wave, the shock wave propagates radially outward from the shock wave generation location within the distal range of the shock wave electrode structure 100. The shock wave energy with a therapeutic effect is defined as effective shock wave energy. The relative position between the two electrodes that form the shock wave through discharge and breakdown affects the propagation direction of the shock wave, thereby affecting the distribution of the effective shock wave energy in space. When the second electrode 20 is spaced apart and sleeved outside the first electrode 10, and the first distal end surface 11 and the second distal end surface 21 are located in the same cross-section of the shock wave electrode structure 100, or when the first electrode 10 and the second electrode 20 are spaced apart and arranged side by side, and the first distal end surface 11 and the second distal end surface 21 are located in the same cross-section of the shock wave electrode structure, the distribution of the effective shock wave energy in space is hemispherical. When the second electrode 20 is spaced apart and sleeved outside the first electrode 10, and the first distal surface 11 is located distal to the second distal surface 21, or when the first electrode 10 and the second electrode 20 are spaced apart and arranged side by side, the electrode closer to the axis of the shock wave electrode structure 100 is located distal to the other electrode (for example, when the distance between the first distal surface 11 and the axis of the shock wave electrode structure 100 is less than the distance between the second distal surface 21 and the axis of the shock wave electrode structure 100, the first distal surface 11 is located distal to the second distal surface 21), the distribution of the effective shock wave energy in space is larger than a hemisphere. Thus, by changing the relative positions of the first distal surface 11 and the second distal surface 21 in space, the distribution of the effective shock wave energy in space can be effectively adjusted, thereby obtaining an effective shock wave energy coverage range with a hemispherical or even larger distribution, so that the shock wave energy covers as much as possible all sclerotic tissues located near the shock wave electrode structure 100 where expansion is impossible or inconvenient, thereby achieving the purpose of treatment.

[0056] In a specific embodiment, the distal surface of the shock wave electrode structure 100 is a plane or a convex surface, and the first distal surface 11 and the second distal surface 21 are located on the plane or the convex surface. By changing the relative positions of the first distal surface 11 and the second distal surface 21 on the plane or the convex surface, an effective shock wave energy coverage range with a distribution shape of hemispherical or even larger than hemispherical is obtained, so that the shock wave energy covers as much as possible all hardened tissues located near the shock wave electrode structure 100 where expansion is impossible or inconvenient, thereby achieving the purpose of treatment. When the distal surface of the shock wave electrode structure 100 is a convex surface, the convex surface is preferably an axisymmetric convex surface structure so that the effective shock wave energy can be relatively evenly distributed in space. The convex surface can be, for example, a spherical cap, a frustum, an ellipsoid, or a paraboloid of rotation. In order to obtain higher single shock wave energy, the electrode corresponding to the smaller of the area of ​​the first distal surface 11 and the area of ​​the second distal surface 21 is the positive electrode. When the area of ​​the first distal surface 11 is smaller than the area of ​​the second distal surface 21, the first electrode 10 is the positive electrode; when the area of ​​the second distal surface 21 is smaller than the area of ​​the first distal surface 11, the second electrode 20 is the positive electrode.

[0057] In order to enable the electrodes to withstand the large amount of heat and impact generated during the shock wave generation process, the materials of the first electrode 10 and the second electrode 20 in the embodiment of the present invention are preferably high-temperature resistant and impact-resistant materials, such as stainless steel, tungsten, tungsten alloys, titanium, titanium alloys, platinum, platinum alloys and other alloys, so that the first electrode 10 and the second electrode 20 can withstand higher applied voltages and stably generate more shock waves with stronger single shock wave energy.

[0058] In addition, the prior art uses a polymer insulating layer to achieve insulation between electrodes. The heat generated by the formation of the shock wave can cause the polymer insulating layer to melt or even degrade and carbonize. At the same time, under the action of thermal energy, the melt formed by the ablation of the electrode and the melt formed by the combustion of the polymer insulating layer mix with each other to form a mixture with extremely weak electrical conductivity. In the absence of a significant increase in the potential difference, these mixtures cannot achieve breakdown discharge. In order to avoid the melt generated after the electrode melts reducing the electrical properties of the electrode, and the melt conduction or the melt generated after the polymer insulating layer melts causing the inability to continue discharge breakdown, the shock wave electrode structure 100 of the present application is further provided with an insulating portion 40 between the first electrode 10 and the second electrode 20. The insulating portion 40 has a distal surface 41. Preferably, the insulating portion 40 is filled between the first electrode 10 and the second electrode 20. Figures 15 to 26 are schematic structural diagrams of the shock wave electrode structure of the present application when it has an insulating portion 40 in the specific embodiments shown in Figures 1 to 14. The insulating portion 40 is made of an insulating material with high breakdown strength (to withstand a greater number of discharge breakdowns at a sufficiently high applied voltage), high heat resistance (to withstand greater heat during the discharge breakdown process), high resistivity (to minimize the impact of the discharge breakdown between the first distal end face 11 and the second distal end face 21), and high mechanical strength (to withstand all impact forces during the entire discharge breakdown process). Because the heat and impact strength generated during the shock wave generated by the discharge breakdown are extremely high, the insulating portion 40 is preferably made of an insulating material with high values ​​for these performance indicators, and the higher the performance indicators, the better. Examples include existing ceramics or minerals (such as artificial diamonds), Bakelite (a type of plastic, chemically known as phenolic plastic), modified impact-resistant glass (available today, such as lead-modified), quartz, or specialized ceramics modified to be more heat-resistant, easier to process, and more impact-resistant. As materials evolve, other materials with higher performance indicators may also be used in the insulating portion 40. Therefore, during the shock wave generation process, the insulating portion 40 does not produce a melt, let alone a mixture containing a melt.

[0059] In the axial projection of the shock wave electrode structure 100 of the present application, the distal surface 41 is flush with the first distal surface 11, flush with the second distal surface 21, or located between the first distal surface 11 and the second distal surface 21. When the first distal surface 11 and the second distal surface 21 are electrically connected to form a shock wave, the shock wave is formed on the distal surface 41. The distal surface 41 can be a flat surface or a convex surface. By changing the shape of the distal surface of the insulating portion 40, the following are achieved: 1) a more precise discharge distance is achieved between the first distal surface 11 and the second distal surface 21; for example, the discharge between the first distal surface 11 and the second distal surface 21 can be made more precise by the insulating portion 40. The distance is basically equal, and a more stable single shock wave energy is obtained while maintaining a stable potential difference between the first electrode 10 and the second electrode 20; 2) the reflection effect of the distal end of the insulating portion 40 on the shock wave is utilized to more accurately adjust the distribution of the shock wave energy in space; 3) the melt generated by electrode ablation cannot remain between the first electrode 10 and the second electrode 20, but is washed away by the impact force of the shock wave on the distal end surface of the shock wave electrode structure of the present application, having a self-cleaning function, and completely solving the problem of melt accumulation on the electrode surface reducing the electrical performance of the electrode, and melt conduction leading to the inability to continue discharge and breakdown. Therefore, through the insulating portion 40, the influence of electrode melting and polymer insulation layer melting on the discharge distance in the prior art, as well as the influence of unknown and unpredictable shock wave occurrence on the spatial distribution of shock wave energy in the prior art, can be basically avoided, thereby obtaining a single shock wave energy and cumulative shock wave energy that are closer to the expected, as well as a shock wave energy spatial distribution that is closer to the expected. For example, when the distal surface of the insulating portion 40 is flat, the shock wave energy caused by the distal ends of the first electrode 10 and the second electrode 20 is transmitted outward in a hemispherical shape of approximately 180°. When the distal surface of the insulating portion 40 is convex, particularly a spherical crown convex, the shock wave energy caused by the distal ends of the first electrode 10 and the second electrode 20 is reflected by the distal surface of the insulating portion 40 and is transmitted outward in a spherical crown shape greater than 180°. It can be seen from this that the insulating portion 40 constrains the direction of the shock wave, and the direction of the shock wave can be controlled by controlling the thickness, height, and surface shape of the insulating portion 40. However, those skilled in the art should be aware that the surface of the insulating portion 40 can be slightly lower than the lower of the first distal surface 11 and the second distal surface 21. This is similar to the situation where the surface of the insulating portion 40 is substantially level with the lower of the first distal surface 11 and the second distal surface 21, and the technical effect is not much different. The surface of the first distal end surface 11 and the second distal end surface 21 that is closer to the proximal end of the shock wave electrode structure 100 of the present application is the lower one. The height of the insulating portion 40 can be obtained through experimental testing.

[0060] As can be seen from the foregoing, the energy of a single shock wave can be controlled by changing the discharge distance between the first distal surface 11 and the second distal surface 21. Specifically, the discharge distance between the first distal surface 11 and the second distal surface 21 is at least one of equal, continuously increasing, and step-wise increasing. Since the shock wave is generated between the two points closest to each other on the first distal surface 11 and the second distal surface 21, the discharge breakdown process when the discharge distance between the first distal surface 11 and the second distal surface 21 continuously decreases is the same as the discharge breakdown process when the discharge distance between the first distal surface 11 and the second distal surface 21 continuously increases. The discharge breakdown process when the discharge distance between the first distal surface 11 and the second distal surface 21 decreases in a step-wise manner is the same as the discharge breakdown process when the discharge distance between the first distal surface 11 and the second distal surface 21 increases in a step-wise manner.

[0061] When the discharge distance between the first distal surface 11 and the second distal surface 21 is equal, if the applied voltage is constant, the magnitude of the single shock wave energy remains basically unchanged. As long as the first electrode 10 and the second electrode 20 are subjected to a suitable applied voltage, any two points closest to the first distal surface 11 and the second distal surface 21 will discharge and break down and quickly melt after the shock wave is formed. If it is desired to obtain the target cumulative shock wave energy in a shorter time, a higher applied voltage can be applied provided that the single shock wave energy meets the safety requirements. Here, "suitable applied voltage" means that the applied voltage is greater than the minimum breakdown voltage between the first distal surface 11 and the second distal surface 21 and less than the maximum effective breakdown voltage between the first distal surface 11 and the second distal surface 21. The "higher applied voltage" here also needs to meet the range of "suitable applied voltage".

[0062] When the discharge distance between the first distal surface 11 and the second distal surface 21 continuously increases, if the applied voltage is constant and the applied voltage is greater than the minimum breakdown voltage of all discharge distances and less than the maximum effective voltage of all discharge distances, it can be understood that the interval between the discharge breakdown to form the shock wave becomes longer and longer, and the energy of a single shock wave becomes larger and larger.

[0063] When the discharge distance between the first distal surface 11 and the second distal surface 21 increases in a step-by-step manner, if the applied voltage is constant and the applied voltage is greater than the minimum breakdown voltage of all discharge distances that increase in a step-by-step manner and less than the maximum effective voltage of all discharge distances that increase in a step-by-step manner, it can be understood that the interval length of the shock wave formed by the discharge breakdown will increase in a step-by-step manner, and the energy of a single shock wave will also increase in a step-by-step manner.

[0064] In summary, by changing the relative spatial position and discharge distance between the first distal end surface 11 and the second distal end surface 21, the spatial distribution and magnitude of the effective shock wave energy can be adjusted. Thus, the discharge distance between the first distal end surface 11 and the second distal end surface 21 can be set according to the required effective shock wave energy.

[0065] The following describes the specific embodiments shown in Figures 1 to 14. By varying the spatial positions of the first electrode 10 and the second electrode 20, different discharge distances are formed between the first distal surface 11 and the second distal surface 21, thereby generating shock waves with varying single shock wave energies. For example, a greater shock wave energy can be applied to more severely hardened lesions. The following structures are all applicable when the distal surface of the shock wave electrode structure 100 is flat or convex, i.e., when the spatial distribution of the effective shock wave energy is hemispherical or larger than a hemisphere.

[0066] In the first type of embodiment, the second electrode 20 is spaced apart and sleeved outside the first electrode 10, and the discharge gap formed between the outer contour of the first distal surface 11 and the inner contour of the second distal surface 21 is the discharge distance between the first distal surface 11 and the second distal surface 21. When a suitable voltage is applied to the first electrode 10 and the second electrode 20, discharge breakdown occurs randomly between the entire outer contour of the first distal surface 11 and the inner contour of the second distal surface 21 to form a shock wave, and the discharge distance between the outer contour of the first distal surface 11 and the inner contour of the second distal surface 21 is at least one of equal and continuously increasing.

[0067] In the first case, the discharge distance between the inner contour of the second distal end face 21 and the outer contour of the first distal end face 11 is equal. The inner contour shape of the second distal end face 21 is an equidistantly expanded shape of the outer contour shape of the first distal end face 11. The equidistantly expanded shape refers to the inner contour of the second distal end face 21, which is a shape formed by equidistantly expanding the outer contour of the first distal end face 11. As a result, a discharge gap of uniform width is formed between the outer contour of the first distal end face 11 and the inner contour of the second distal end face 21. In the process of discharge breakdown between the first distal end face 11 and the second distal end face 21 to form a shock wave, the time interval of the shock wave is almost unchanged, and the energy of a single shock wave is almost equal. In the specific embodiment shown in Figure 1, the first distal end face 11 is circular (or annular), the second distal end face 21 is annular, and the second distal end face 21 is coaxially sleeved on the outer periphery of the first distal end face 11. The axis of the first electrode 10, the axis of the second electrode 20, and the axis of the shock wave electrode structure 100 overlap, so that the shock wave energy can be uniformly distributed in space at the distal end of the shock wave electrode structure. The first distal surface 11 can also be elliptical or elliptical ring, and the second distal surface 21 is an elliptical ring that expands equidistantly from the first distal surface 11. In order to further increase the breakdown length of the first electrode 10 and the second electrode 20, the outer contour of the first distal surface 11 and the inner contour of the second distal surface 21 can also be wavy, so that discharge and breakdown can be formed along the outer contour of the entire wavy first distal surface 11 to form a shock wave.

[0068] In the second case, the discharge distance between the inner contour of the second distal surface 21 and the outer contour of the first distal surface 11 continuously increases. During the process of shock wave formation caused by the discharge breakdown between the first distal surface 11 and the second distal surface 21, the time interval between the shock waves gradually increases, and the energy of a single shock wave gradually increases. In the specific embodiment shown in Figure 2, the first distal surface 11 is circular (or may be annular, elliptical, or elliptical-annular), the second distal surface 21 is elliptical-annular (or may be annular), and the axis of the second distal surface 21 is spaced apart from the axis of the first distal surface 11, that is, the second electrode 20 is non-concentrically arranged on the periphery of the first electrode 10.

[0069] In the third scenario, the discharge distance between the inner contour of the second distal end surface 21 and the outer contour of the first distal end surface 11 includes both an equal portion and a continuously increasing portion. During the process of shock wave formation caused by the discharge breakdown between the first distal end surface 11 and the second distal end surface 21, in the portion where the discharge distance is equal, the time interval between the shock waves remains almost constant and the energy of a single shock wave is almost equal. In the portion where the discharge distance continuously increases, the time interval between the shock waves gradually increases and the energy of a single shock wave gradually increases. As shown in Figure 3, the first distal end surface 11 includes two parallel sides, and these two parallel sides respectively connect with two arcs. The second distal end surface 21 is an oval shape (the two parallel sides of a long rectangle respectively connect with two semicircles). At the location of the two parallel sides of the first distal end surface 11, the discharge distance between the inner contour of the second distal end surface 21 and the outer contour of the first distal end surface 11 is equal. At the arc position of the first distal end surface 11, the discharge distance between the inner contour of the second distal end surface 21 and the outer contour of the first distal end surface 11 continuously increases.

[0070] In the second type of embodiment, the first electrode 10 and the second electrode 20 are arranged side by side with an interval, and a discharge gap formed between a portion of the first distal surface 11 adjacent to the second distal surface 21 and a portion of the second distal surface 21 adjacent to the first distal surface 11 is the discharge distance between the first distal surface 11 and the second distal surface 21. When a suitable voltage is applied to the first electrode 10 and the second electrode 20, discharge breakdown randomly occurs between adjacent portions of the first distal surface 11 and the second distal surface 21 to form a shock wave, and the discharge distance between the portion of the first distal surface 11 adjacent to the second distal surface 21 and the portion of the second distal surface 21 adjacent to the first distal surface 11 is at least one of equal and continuously increasing.

[0071] In the first case, the discharge distances between the portion of the first distal surface 11 adjacent to the second distal surface 21 and the portion of the second distal surface 21 adjacent to the first distal surface 11 are equal. Those skilled in the art will appreciate that the distance between the portion of the first distal surface 11 adjacent to the second distal surface 21 and the portion of the second distal surface 21 adjacent to the first distal surface 11 is the shortest distance between the first distal surface 11 and the second distal surface 21. In the specific embodiment shown in FIG4 , the first distal surface 11 and the second distal surface 21 are both rectangular, and the long sides of the rectangles of the first distal surface 11 and the second distal surface 21 are arranged parallel and spaced apart. In this embodiment, the distances between the long sides of the rectangles of the first distal surface 11 and the second distal surface 21 are equal and are the shortest distance between the first distal surface 11 and the second distal surface 21. In the specific embodiment shown in FIG5 , the first distal face 11 and the second distal face 21 are both right-angled trapezoids, and the right-angled waist of the first distal face 11 is spaced parallel to the right-angled waist of the second distal face 21. In other words, regardless of whether the width of the first distal face 11 is uniform along the extension direction of the first distal face 11, or whether the width of the second distal face 21 is uniform along the extension direction of the second distal face 21, it is sufficient to ensure that there is at least one interval between the first distal face 11 and the second distal face 21, which is the same and the shortest interval between the first distal face 11 and the second distal face 21. It should be understood by those skilled in the art that a first distal face 11 being a right-angled trapezoid and the second distal face 21 being a rectangle, or a first distal face 11 being a rectangle and the second distal face 21 being a right-angled trapezoid, is also within the scope of protection of this application. In the specific embodiments shown in Figures 4 and 5, the two parallel sides between the first distal face 11 and the second distal face 21 are both straight lines. People skilled in the art should understand that a curved side in the first distal face 11 and a curved side in the second distal face 21 that are parallel are also within the scope of protection of this application.

[0072] In the second case, the discharge distance between the portion of the first distal end surface 11 adjacent to the second distal end surface 21 and the portion of the second distal end surface 21 adjacent to the first distal end surface 11 continuously increases. In a simple exemplary embodiment shown in FIG6 , the first distal end surface 11 and the second distal end surface 21 are both rectangular, the long sides of the two rectangular structures are spaced apart, and the spacing between the two rectangular structures continuously increases.

[0073] In the third case, the discharge distance between the portion of the first distal end surface 11 adjacent to the second distal end surface 21 and the portion of the second distal end surface 21 adjacent to the first distal end surface 11 includes both an equal portion and a continuously increasing portion. In the specific embodiment shown in FIG7 , the discharge distance between the first distal end surface 11 and the second distal end surface 21 first continuously increases and then remains equal.

[0074] Taking the embodiment shown in FIG. 8 as an example, the influence of the change in the applied voltage on the energy of a single shock wave will be described. The discharge distances between the first distal end face 11 and the second distal end face 21 are L1, L2, L3, and L4 in ascending order, and the corresponding minimum breakdown voltages of L1, L2, L3, and L4 are U01, U02, U03, and U04, respectively. Let the applied voltage be U0 and remain unchanged. Assuming that when the applied voltage is U0, the discharge distance between the first distal end face 11 and the second distal end face 21 is L0. In the first stage, U01 < U0 < U02, partial discharge breakdown occurs in the part where the condition L1 ≤ L0 < L2 is satisfied between the first distal end face 11 and the second distal end face 21. As the discharge breakdown continues, the discharge distance between the first distal end face 11 and the second distal end face 21 gradually increases, and the energy of a single shock wave gradually increases, as shown by the E1 segment in FIG. 9. Since U0 < U02, the position where the discharge distance between the first distal end face 11 and the second distal end face is L2 cannot be discharged and broken down. In the second stage, U0 is increased until U02 < U0 < U03 and then remains unchanged. Partial discharge breakdown occurs in the part where the condition L2 ≤ L0 < L3 is satisfied between the first distal end face 11 and the second distal end face 21. Similarly, as the discharge breakdown continues, the discharge distance between the first distal end face 11 and the second distal end face gradually increases, and the energy of a single shock wave gradually increases, as shown by the E2 segment in FIG. 9, until the discharge distance between the first distal end face 11 and the second distal end face reaches L3 and the breakdown discharge terminates. Since U0 increases from the first stage to the second stage, there is an abrupt increase in energy from E1 to E2. In the third stage, U0 is increased until U0 ≥ U04. Under sufficient duration, the first distal end face 11 and the second distal end face 21 complete all discharge breakdowns, and the change in the energy of a single shock wave is as shown by the E3 segment in FIG. 9. Similarly, there is also an abrupt increase in energy from E2 to E3.

[0075] Furthermore, the first distal end face 11 and the second distal end face 21 can also adopt a multi-segment structure. By changing the connection method of the wire to the first electrode 10 and the second electrode 20, the energy distribution of the shock wave in space can be changed. ​In the third type of embodiments, the first distal end face 11 has a multi-segment structure, and the discharge distance between each segment of the first distal end face 11 and the second distal end face 21 is less than the sum of the discharge distance between this segment of the first distal end face 11 and its nearest adjacent another segment of the first distal end face 11 and the discharge distance between the nearest adjacent another segment of the first distal end face 11 and the second distal end face 21. If the second electrode 20 is sleeved on the first electrode 10 at intervals, that is, multiple segments of the first distal end face 11 are arranged inside the second distal end face 21, the discharge distance between the outer contour of each segment of the first distal end face 11 and the inner contour of the second distal end face 21 is at least one of being equal, continuously increasing, and stepwise increasing. If the first electrode 10 and the second electrode 20 are arranged side by side at intervals, the discharge distance between the part of each segment of the first distal end face adjacent to the second distal end face and the part of the second distal end face adjacent to the first distal end face is at least one of being equal, continuously increasing, and stepwise increasing.

[0077] In a simple embodiment shown in FIG. 10, the second distal end face 21 has a rectangular structure, and the first distal end face 11 includes a first distal end face first segment 1101, a first distal end face second segment 1102, and a first distal end face third segment 1103 that are arranged in sequence on one side of the second distal end face 21. The discharge distance between the first distal end face first segment 1101 and the second distal end face 21 is equal and is a1, and the minimum breakdown voltage of a1 is U1. The discharge distance between the first distal end face second segment 1102 and the second distal end face 21 is equal and is a2, and the minimum breakdown voltage of a2 is U2. The discharge distance between the first distal end face third segment 1103 and the second distal end face 21 is equal and is a3, and the minimum breakdown voltage of a3 is U3. Since a1 < a2 < a3, so U1 < U2 < U3.

[0078] When the three segments of the first distal end face 11 are connected to the same wire, the applied voltage is U'. By adjusting the magnitude of the applied voltage, different changes in shock wave energy can be obtained. If U1 < U' < U2, only the first distal end face first segment 1101 and the second distal end face 21 discharge and break down to form a shock wave, and the single-shot shock wave energy is basically stable. If U' > U, in the first stage, the first distal end face first segment 1101 and the second distal end face 21 discharge and break down to form a shock wave, and the single-shot shock wave energy is basically stable until the first distal end face first segment 1101 is completely melted; in the second stage, the first distal end face second segment 1102 and the second distal end face 21 discharge and break down to form a shock wave, and the single-shot shock wave energy is basically stable until the first distal end face second segment 1102 is completely melted; in the third stage, the first distal end face third segment 1103 and the second distal end face 21 discharge and break down to form a shock wave, and the single-shot shock wave energy is basically stable; during the entire discharge process, the change in the single-shot shock wave energy is shown in FIG. 11, first basically stable, then experiencing two sudden increases, and remaining basically stable after the increase. Those skilled in the art should be able to understand the energy change of the shock wave obtained when U2 < U' < U3, and will not be elaborated here.

[0079] When each of the three segments of the first distal end face 11 is connected to a wire, taking the second segment 1102 of the first distal end face as an example, the discharge interval between the second segment 1102 of the first distal end face and the first segment 1101 of the first distal end face is a201, and the discharge interval between the second segment 1102 of the first distal end face and the third segment 1103 of the first distal end face is a203. As shown in FIG. 10, a201 > a203. When a2 < a3 + a203, a2 < a3 + a201 also holds. A voltage U'' is applied between the second segment 1102 of the first distal end face and the second distal end face 21, and U'' > U2. Since the shortest discharge distance between the second segment 1102 of the first distal end face and the second distal end face 21 is a2, only the discharge breakdown and the formation of a shock wave occur between the second segment 1102 of the first distal end face and the second distal end face 21, and the first segment 1101 and the third segment 1103 of the first distal end face have no influence on this discharge process. Those skilled in the art should understand that if only the discharge breakdown and the formation of a shock wave between the first segment 1101 or the third segment 1103 of the first distal end face and the second distal end face 21 are required, it can be achieved by adjusting the magnitude of U''. Thus, the energy magnitude of the shock wave can be selected according to the sclerosis degree of the sclerotic tissue at the lesion site.

[0080] In the fourth type of embodiment, the second distal end face 21 is a multi-segment structure, and the discharge distance between each segment of the second distal end face 21 and the first distal end face 11 is less than the sum of the discharge distance between this segment of the second distal end face 21 and its nearest adjacent other segment of the second distal end face 21 and the discharge distance between the nearest adjacent other segment of the second distal end face 21 and the first distal end face 11. If the second electrode 20 is sleeved outside the first electrode 10 at intervals, the discharge distance between the inner contour of each segment of the second distal end face 21 and the outer contour of the first distal end face 11 is at least one of being equal, continuously increasing, and increasing step by step. If the first electrode 10 and the second electrode 20 are arranged side by side at intervals, the discharge distance between the part of each segment of the second distal end face 21 adjacent to the first distal end face 11 and the part of the first distal end face 11 adjacent to the second distal end face 21 is at least one of being equal, continuously increasing, and increasing step by step. Preferably, the segments of the second distal end face 21 are arranged at uniform intervals.

[0081] In a preferred embodiment, as shown in Figure 12, the first distal surface 11 is annular, and the second distal surface 21 includes a first sub-electrode segment 211, a second sub-electrode segment 212, and a third sub-electrode segment 213, all of which are arc-shaped and have equal diameters. These three arc-shaped segments are evenly spaced and concentrically arranged around the circular periphery of the first distal surface 11. When each of the three segments of the second distal surface 21 is connected to a wire, the region and frequency of shock waves with equal energy can be selected. For example, when the applied voltage is U″ and the required number of shock wave inductions is N, the number of shock wave occurrences between the first sub-electrode segment 211 and the first distal surface 11, the number of shock wave occurrences between the second sub-electrode segment 212 and the first distal surface 11, and the number of shock wave occurrences between the third sub-electrode segment 213 and the first distal surface 11 are all controlled to be N / 3, thereby achieving a relatively uniform spatial distribution of shock wave energy. Alternatively, the shock wave generation region can be selected based on the location of the sclerotic tissue at the lesion site, without having to adjust the shock wave balloon catheter using this electrode structure. When the three segments of the second distal surface 21 are connected to the same wire, shock waves randomly occur between each segment of the second distal surface 21 and the first distal surface 11. In actual experiments, it was found that compared with the embodiment shown in FIG1 , in which the shock wave randomly occurs between the outer circumference of the first distal surface 11 and the inner circumference of the second distal surface 21, configuring the second distal surface 21 as a three-segment arc structure with uniform spacing also results in a more uniform distribution of shock wave energy in space.

[0082] In another preferred embodiment, as shown in FIG13 , the first distal surface 11 is circular, and the second distal surface 21 includes a first second distal surface segment 2101, a second second distal surface segment 2102, a third second distal surface segment 2103, and a fourth second distal surface segment 2104, all of which are arc-shaped structures with successively increasing diameters. The central angles of these four arc structures are the same, and the angles between the central angles of two adjacent arc structures are the same. Simultaneously, these four arc structures are concentrically arranged around the circular periphery of the first distal surface 11. Similar to the embodiment shown in FIG12 , when each of the four segments of the second distal surface 21 is connected to a wire, the location and frequency of shock waves can be selected. However, the discharge distance between each arc structure and the first distal surface 11 is different, and the energy of the resulting shock waves is also different. By rotating a shock wave balloon catheter with this electrode structure, a more energetic shock wave can be delivered to a location where the sclerotic tissue in the lesion is more severe.

[0083] In the fifth type of embodiment, the first distal surface 11 and the second distal surface 21 are both multi-segment structures; if the second electrode 20 is arranged outside the first electrode 10 at intervals, the discharge distance between the outer contour of each segment of the first distal surface and the inner contour of at least one segment of the second distal surface is equal, continuously increasing, and step-increasing; if the first electrode 10 and the second electrode 20 are arranged side by side at intervals, the discharge distance between the portion adjacent to each segment of the first distal surface 11 and the second distal surface 21 and the portion adjacent to the second distal surface 21 is equal, continuously increasing, and step-increasing.

[0084] In one embodiment, as shown in Figure 14, both the first distal surface 11 and the second distal surface 21 are constructed with four rectangular segments. The four rectangular segments of the second distal surface 21 correspond one-to-one with the four rectangular segments of the first distal surface 11, forming four electrode pairs. The distance between the two rectangular segments in each electrode pair is equal. By selecting the electrode pairs that generate the shock wave through discharge, the location and frequency of shock wave initiation can be controlled.

[0085] An embodiment of the present invention further provides a shock wave balloon catheter comprising the shock wave electrode structure 100 described above, a catheter body, and an expansion element 30 capable of being filled with a conductive liquid. The expansion element 30 is sealed to the distal end of the catheter body, and the first distal end surface 11 and the second distal end surface 21 of the shock wave electrode structure 100 are both located within the expansion element 30. When the expansion element 30 is filled with a conductive liquid and a voltage is applied to the first electrode 10 and the second electrode 20 of the shock wave electrode structure, shock waves are only induced between the first distal end surface 11 and the second distal end surface 21. The catheter body includes the catheter body that enters the human body and other external parts, such as a handle, side branches, and other circuit and fluid interfaces.

[0086] As can be seen from the description of the prior art, when using the liquid-electric method to form shock waves, small bubbles will form on the discharge surface of the first electrode 10 and the second electrode 20, and large bubbles will also form in the conductive liquid. The small bubbles accumulated on the discharge surface will affect the conductive properties of the conductive liquid, thereby affecting the discharge breakdown between the first distal end face 11 and the second distal end face 21. The large bubbles in the conductive liquid will affect the intensity of the shock wave (the size of the shock wave energy) during the shock wave transmission process. To this end, the shock wave balloon catheter of the present application is further provided with a circulation system of the conductive liquid, so that the conductive liquid can flow during the discharge breakdown process, so that the large and small bubbles can be carried away by the flowing conductive liquid.

[0087] The shock wave electrode structure 100 of the present application may further include a through-cavity, which serves as a guidewire cavity or a fluid inflow cavity 50 for a conductive liquid. When the through-cavity of the shock wave electrode structure 100 serves as the fluid inflow cavity 50 for a conductive liquid, the tube body may be provided with a fluid discharge cavity 60, wherein the outflow port of the fluid inflow cavity 50 and the inflow port of the fluid discharge cavity 60 are both located within the expansion element 30, thereby forming a circulation system for the conductive liquid. The conductive liquid enters the fluid inflow cavity 50 and flows through the discharge surface between the first distal end face 11 and the second distal end face 21, and then flows out through the fluid discharge cavity 60, carrying away large bubbles in the conductive liquid and small bubbles formed on the discharge surfaces of the first electrode 10 and the second electrode 20, and flushing the first distal end face 11 and the second distal end face 21. Alternatively, the shock wave electrode structure 100 further includes a through first fluid inlet cavity and a through first fluid discharge cavity; the distance between the first fluid inlet cavity and the axis of the shock wave electrode structure 100 is less than the distance between the first fluid discharge cavity and the axis of the shock wave electrode structure 100. The conductive liquid enters the first fluid inlet cavity and flows out through the first fluid discharge cavity, carrying away large bubbles in the conductive liquid and small bubbles formed on the discharge surfaces of the first electrode 10 and the second electrode 20, and flushing the first distal surface 11 and the second distal surface 21. When the shock wave electrode structure 100 includes the first fluid inlet cavity and the first fluid discharge cavity, the outflow port of the first fluid inlet cavity and the inflow port of the first fluid discharge cavity are both located within the expansion element 30. Neither the fluid inlet cavity 50, the first fluid inlet cavity, nor the first fluid discharge cavity should be disposed within the discharge gap between the first distal surface 11 and the second distal surface 21 to avoid affecting the insulation environment between the first distal surface 11 and the second distal surface 21. Alternatively, the through cavity of the shock wave electrode structure 100 of the present application is used as a guide wire cavity, and when the tube body has a second fluid inlet cavity and a second fluid discharge cavity, the outflow port of the second fluid inlet cavity and the inflow port of the second fluid discharge cavity are located in the expansion element 30, and the conductive liquid enters from the second fluid inlet cavity and flows out through the second fluid discharge cavity, taking away large bubbles in the conductive liquid and small bubbles formed on the discharge surfaces of the first electrode 10 and the second electrode 20.

[0088] Taking the shock wave electrode structure 100 shown in FIG27 as an example, the second electrode 20 is coaxially sleeved outside the first electrode 10. The first distal surface 11 is annular, and the second distal surface 21 is composed of three equally spaced and coaxially arranged arcs of equal diameter. The first electrode 10 has a central through-hole. An insulating portion 40 is disposed between the first electrode 10 and the second electrode 20. The first distal surface 11, the distal surface 41 of the insulating portion 40, and the second distal surface 21 are located on the same smooth convex surface, which is the distal surface of the shock wave electrode structure. The first distal surface 11 is closer to the distal end than the second distal surface 21. An insulating member 70 made of an insulating material is filled between the three equally spaced arcs of the second distal surface 21. This insulating material can be a polymer insulating material used in the prior art, or it can be the same insulating material as the insulating portion 40.

[0089] In one embodiment, the central through-hole of the first electrode 10 serves as the fluid inlet cavity 50. As shown in FIG28 , the expansion element 30 of the shock wave balloon catheter is a blind-end balloon, and the tube body 80 is provided with a fluid discharge cavity 60. The blind-end balloon refers to a balloon with a closed distal end. During the process of generating the shock wave, the conductive liquid continuously flows from the fluid inlet cavity 50 into the blind-end balloon and out of the fluid discharge cavity 60, which not only carries away large bubbles in the conductive liquid and small bubbles formed on the discharge surfaces of the first electrode 10 and the second electrode 20, but also washes the first distal surface 11 and the second distal surface 21. Under the action of the reverse shock wave, the molten metal on the first distal surface 11 and the second distal surface 21 is carried away. During use, the shock wave balloon catheter is first placed near the tissue to be treated in the human body, and a conductive liquid is injected and pressurized through the fluid inlet cavity 50 so that the blind-end balloon is close to or against the tissue to be treated; the first distal surface 11 and the second distal surface 21 are discharged and broken down to form a shock wave, and the target shock wave energy value is obtained. At a set frequency, the shock wave is released for a set time to obtain the cumulative shock wave energy required for treatment until the treatment is completed; in the process of releasing the shock wave, the conductive liquid is made to flow to carry away the bubbles and the smaller electrode melt in the blind-end balloon. The conductive liquid can flow continuously or flow in the gaps between the shock waves to complete the replacement of the conductive liquid.

[0090] Still taking the shock wave electrode structure 100 of this structure as an example, with the central through-hole of the first electrode 10 serving as the guidewire lumen, the expansion element 30 of the shock wave balloon catheter is a balloon having a central cavity. The tube body not only has a second fluid inlet lumen and a second fluid discharge lumen, but also has a lumen for passing a guidewire. This central cavity is connected to the central through-hole (guidewire lumen) of the first electrode 10. The guidewire can pass through the lumen of the tube body, sequentially enter the central through-hole (guidewire lumen) of the first electrode 10 and the central cavity of the expansion element, and extend from the distal end of the central cavity of the expansion element. This guidewire can be used to quickly and accurately deliver the shock wave balloon catheter to the lesion site.

[0091] From the above, it can be seen that the shock wave electrode structure 100 and shock wave balloon catheter of the present application have a larger electrode effective melting volume, can withstand a sufficiently high applied voltage a sufficient number of times, and under appropriate applied voltage and electrode distance, have more shock wave initiation times and greater cumulative shock wave energy, and can continuously perform shock wave treatment on the tissue to be treated in the area that cannot or is inconvenient to expand, so that the hardened tissue in the area that cannot or is inconvenient to expand can be treated by using only shock wave energy.

[0092] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A shock wave electrode structure, characterized in that: include: A first electrode and a second electrode are spaced apart and extend in the same direction; The first electrode has a first distal surface, and the second electrode has a second distal surface. When the first distal surface and the second distal surface are located in a conductive liquid and voltage is applied to the first electrode and the second electrode, a shock wave can be generated only between the first distal surface and the second distal surface.

2. The shock wave electrode structure according to claim 1, characterized in that: The second electrode is sleeved outside the first electrode, and the first distal end surface and the second distal end surface are located in the same cross section; or, The second electrode is sleeved outside the first electrode with a gap, and the first distal end surface is located at the distal end of the second distal end surface; or, The first electrode and the second electrode are spaced apart and arranged side by side, and the first distal end surface and the second distal end surface are located in the same cross section; or, The first electrode and the second electrode are arranged side by side with an interval, the distance between the first distal end surface and the axis of the tube body is smaller than the distance between the second distal end surface and the axis of the tube body, and the first distal end surface is located distal to the second distal end surface.

3. The shock wave electrode structure according to claim 2, characterized in that: The discharge distance between the first distal end surface and the second distal end surface is at least one of equal, continuously increasing, and step-increasing.

4. The shock wave electrode structure according to claim 3, characterized in that: When the second electrode is spaced apart and sleeved outside the first electrode, the discharge distance between the inner contour of the second distal end surface and the outer contour of the first distal end surface is at least one of equal and continuously increasing; or, When the first electrode and the second electrode are spaced apart and arranged side by side, the discharge distance between the portion of the first distal end surface adjacent to the second distal end surface and the portion of the second distal end surface adjacent to the first distal end surface is at least one of equal and continuously increasing; or The first distal end surface is a multi-segment structure, and the discharge distance between each segment of the first distal end surface and the second distal end surface is smaller than the sum of the discharge distance between the segment of the first distal end surface and the nearest adjacent segment of the first distal end surface and the discharge distance between the nearest adjacent segment of the first distal end surface and the second distal end surface; if the second electrode is spaced and sleeved on the first electrode, the discharge distance between the outer contour of each segment of the first distal end surface and the inner contour of the second distal end surface is at least one of equal, continuously increasing, and step-increasing; if the first electrode and the second electrode are spaced and arranged side by side, the discharge distance between the portion of each segment of the first distal end surface adjacent to the second distal end surface and the portion of the second distal end surface adjacent to the first distal end surface is at least one of equal, continuously increasing, and step-increasing; or, The second distal end surface is a multi-segment structure, and the discharge distance between each segment of the second distal end surface and the first distal end surface is smaller than the sum of the discharge distance between the segment of the second distal end surface and its nearest adjacent segment of the second distal end surface and the discharge distance between the nearest adjacent segment of the second distal end surface and the first distal end surface; if the second electrode is spaced and sleeved outside the first electrode, the discharge distance between the inner contour of each segment of the second distal end surface and the outer contour of the first distal end surface is at least one of equal, continuously increasing, and step-increasing; if the first electrode and the second electrode are spaced and arranged side by side, the discharge distance between the portion of each segment of the second distal end surface adjacent to the first distal end surface and the portion of the first distal end surface adjacent to the second distal end surface is at least one of equal, continuously increasing, and step-increasing; or, The first distal end surface and the second distal end surface are both multi-segment structures; if the second electrode is spaced and sleeved outside the first electrode, the discharge distance between the outer contour of each segment of the first distal end surface and the inner contour of at least one segment of the second distal end surface is at least equal, continuously increasing, and step-increasing; if the first electrode and the second electrode are spaced and arranged side by side, the discharge distance between the portion adjacent to each segment of the first distal end surface and the second distal end surface and at least one segment of the second distal end surface and the first distal end surface is at least equal, continuously increasing, and step-increasing.

5. The shock wave electrode structure according to claim 4, characterized in that: When the first distal end surface is a multi-segment structure, the segments of the first distal end surface are evenly spaced; when the second distal end surface is a multi-segment structure, the segments of the second distal end surface are evenly spaced; when both the first distal end surface and the second distal end surface are multi-segment structures, the segments of the first distal end surface are evenly spaced, and the segments of the second distal end surface are evenly spaced.

6. The shock wave electrode structure according to claim 3, characterized in that: The second distal end surface is coaxially sleeved on the outer periphery of the first distal end surface, the first distal end surface is circular or annular, and the second distal end surface is annular; or, the axis of the second distal end surface is spaced apart from the axis of the first distal end surface, the first distal end surface is circular, annular, elliptical, elliptical annular, multi-segment arc or multi-segment elliptical arc, and the second distal end surface is annular, elliptical annular, multi-segment arc or multi-segment elliptical arc; or, The first electrode and the second electrode are arranged side by side with an interval, the first distal surface is a rectangle or a right-angled trapezoid, the second distal surface is a rectangle or a right-angled trapezoid, the long side or right-angled side of the first distal surface is parallel to the long side or right-angled side of the second distal surface, and the interval distance gradually increases or the interval distance increases in steps.

7. The shock wave electrode structure according to any one of claims 1 to 6, characterized in that: The first distal end surface is a plane or a curved surface, and the second distal end surface is a plane or a curved surface; or, The distal end surface of the shock wave electrode structure is a plane or a convex surface, and the first distal end surface and the second distal end surface are located on the plane or the convex surface; or When the area of ​​the first distal end surface is smaller than the area of ​​the second distal end surface, the first electrode is a positive electrode; when the area of ​​the second distal end surface is smaller than the area of ​​the first distal end surface, the second electrode is a positive electrode; or, The material of the first electrode and the material of the second electrode include stainless steel, tungsten, tungsten alloy, titanium, titanium alloy, platinum, platinum alloy and other alloys; or, It also includes an insulating portion, which is provided between the first electrode and the second electrode; or Also includes a through cavity; or, It also includes a through first fluid inlet cavity and a through first fluid discharge cavity; the distance between the first fluid inlet cavity and the axis of the shock wave electrode structure is smaller than the distance between the first fluid discharge cavity and the axis of the shock wave electrode structure.

8. The shock wave electrode structure according to claim 7, characterized in that: The second electrode is coaxially arranged outside the first electrode, the first distal surface is annular, and the second distal surface is three equal-diameter arcs arranged coaxially at equal intervals. The first electrode has a central through cavity; an insulating portion is provided between the first electrode and the second electrode; the first distal surface, the distal surface of the insulating portion, and the second distal surface are located on the same smooth convex surface, and the first distal surface is closer to the distal end than the second distal surface.

9. A shock wave balloon catheter, characterized in that: include: The shock wave electrode structure, the tube body, and the expansion element capable of being filled with a conductive liquid as described in claims 1-8; the expansion element is sealed and connected to the distal end of the tube body, and the first distal end face and the second distal end face of the shock wave electrode structure are both located within the expansion element; when the expansion element is filled with a conductive liquid and a voltage is applied to the first electrode and the second electrode of the shock wave electrode structure, a shock wave can be induced only between the first distal end face and the second distal end face.

10. The shock wave balloon catheter according to claim 9, characterized in that: When the shock wave electrode structure has a through cavity, the tube body is provided with a fluid discharge cavity, and the outflow port of the through cavity and the inflow port of the fluid discharge cavity are both located in the expansion element; or, When the shock wave electrode structure has a first fluid inlet cavity and a first fluid discharge cavity, the outflow port of the first fluid inlet cavity and the inlet port of the first fluid discharge cavity are located in the expansion element; or, The tube body has a second fluid inlet cavity and a second fluid discharge cavity, and the outflow port of the second fluid inlet cavity and the inlet port of the second fluid discharge cavity are located in the expansion element.

Images