Ablation catheter with a heating element formed by electroplating for treating venous aneurysms

Abstract

At least some embodiments of the present disclosure relate to a catheter for use in the treatment of aneurysms, comprising a handle, an elongate shaft connected to the handle, and a heating element disposed in the vicinity of the distal end of the shaft. In some embodiments, the heating element includes an electrically conductive trace defining a plurality of parallel segments disposed along the length of a tubular polymer member, and arcuate segments disposed between and connecting the parallel segments.

Description

Technical Field

[0001] The present disclosure relates to medical devices, systems, and methods for providing therapeutic heat treatment. More specifically, the present disclosure relates to medical devices, systems, and methods for providing therapeutic heat treatment for venous diseases.

Background Art

[0002] Therapeutic heat treatment can be used to treat a variety of medical conditions such as tumors, fungal growths, etc. Heat treatment can be used to treat medical conditions in parallel with other treatment methods or as a standalone treatment method. Since heat treatment performs local heating, it does not cause cumulative toxicity, in contrast to other treatment methods such as drug-based treatments.

[0003] One exemplary clinical application of therapeutic heat treatment is the treatment of chronic venous diseases such as venous aneurysms that can expand and / or serpentine due to one or more pathological conditions. By applying sufficient thermal energy through an intravascular device, the venous aneurysm can be treated by contracting or occluding the target vein.

[0004] There is a continuing need for improved devices and methods for delivering intensively controlled thermal energy while minimizing or eliminating the impact on surrounding healthy tissue for thermally treating chronic venous conditions such as venous aneurysms.

Summary of the Invention

[0005] In Example 1, the device for treating an aneurysm includes a catheter. The catheter includes a long shaft having a proximal end and a distal end, the size of the distal end being determined and configured such that it can be inserted into a target blood vessel, and an ablation element disposed near the distal end of the long shaft. In some embodiments, the ablation element includes a tubular polymer member connected to the long shaft, and a heating element disposed on the tubular polymer member. The heating element includes an electrically conductive trace that defines a plurality of parallel segments disposed along the length of the tubular polymer member and one or more arch-shaped segments, at least one of the one or more arch-shaped segments being disposed between two adjacent parallel segments of the plurality of parallel segments and connecting the two adjacent parallel segments.

[0006] In Example 2, in the device of Example 1, the electrically conductive trace has a meandering shape formed by a plurality of parallel segments and one or more arch-shaped segments, and the plurality of parallel segments are spaced apart from each other longitudinally or circumferentially on the tubular polymer member.

[0007] In Example 3, in the device of Example 2, the plurality of parallel segments extend longitudinally along the tubular polymer member and are spaced apart from each other circumferentially. In Example 4, in the device of Example 2, the plurality of parallel segments extend circumferentially around the tubular polymer member and are spaced apart from each other longitudinally.

[0008] In Example 5, in the device of Example 1, the plurality of parallel segments are spirally wound around the tubular polymer member. In Example 6, in any of the devices of Examples 1 - 5, the heating element is disposed on the outer surface of the tubular polymer member.

[0009] In Example 7, in any of the devices of Examples 1 - 5, at least a portion of the heating element is disposed on the inner surface of the tubular polymer member. In Example 8, in any of the devices of Examples 1 to 7, the heating element includes a Ni-Cr alloy.

[0010] In Example 9, in any of the devices of Examples 1 to 7, the heating element includes a carbon film. In Example 10, in any of the devices of Examples 1 to 9, the plurality of parallel segments are spaced apart at equal intervals.

[0011] In Example 11, in the device of Example 8, the Ni-Cr alloy is formed on a tubular polymer member by electroplating or spray treatment. In Example 12, in the device of Example 9, the carbon film is formed on a tubular polymer member by electroplating or spray treatment.

[0012] In Example 13, a system for treating an aneurysm includes any of the devices of Examples 1 to 12, an energy generator connected to a long catheter and configured to generate an electrical signal, and a controller operably connected to the energy generator and configured to control the generation of the electrical signal.

[0013] In Example 14, in the system of Example 13, the heating element is electrically connected to the energy generator. In Example 15, in the system of Example 13, the device includes one or more pressure sensors configured to generate an output signal indicating the applied pressure, and the controller is configured to adjust the electrical signal supplied to the heating element based on the output signal.

[0014] Although multiple embodiments are disclosed, further other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description showing and explaining exemplary embodiments of the present invention. Therefore, the drawings and the detailed description should be regarded as being essentially exemplary and not limiting.

Brief Description of the Drawings

[0015]

Figure 1

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Mode for Carrying Out the Invention

[0016] Although the present invention is capable of following various modified forms and alternative forms, specific embodiments are shown in the drawings as examples and will be described in detail below. However, the intention is not to limit the present invention to the specific embodiments described. On the contrary, the present invention is intended to embrace all modified forms, equivalents, and alternative forms included within the scope of the present invention as defined by the appended claims.

[0017] The following detailed description is exemplary in nature and is not intended to limit the scope, applicability, or configuration of the present invention in any way. Rather, the following description provides some practical exemplifications for implementing exemplary embodiments of the present invention. Examples of configurations, materials, and / or dimensions are provided for the selected elements. Those skilled in the art will recognize that there are various suitable alternative means for many of the examples described.

[0018] Thermal treatment can be used to treat a wide variety of medical conditions, including chronic venous diseases such as venous aneurysms that can expand and / or serpentine due to one or more pathological conditions. By applying sufficient thermal energy through an intravascular device, venous aneurysms can be treated by contracting or occluding the target vein.

[0019] An exemplary catheter for use in treating venous aneurysms can include a handle, a long shaft connected to the handle, and a heating element disposed near the distal end of the shaft. In some embodiments, the heating element can receive an electric current (e.g., alternating current, direct current) supplied by an energy generator and generate and supply thermal ablation energy. In certain embodiments, the heating element can receive an electrical signal (e.g., high-frequency alternating current) generated by an energy generator and generate and supply high-frequency ablation energy.

[0020] As described above, there is a continuing need for improved devices and methods for delivering intensively controlled thermal energy while minimizing or eliminating effects on surrounding healthy tissue for the thermal treatment of chronic venous conditions such as varicose veins. For example, catheters used to treat target blood vessels are preferably somewhat flexible to minimize potential unwanted damage to the vessel wall during treatment. Certain embodiments of the present disclosure can improve the efficiency of the heating treatment while maintaining a degree of flexibility of the catheter. Alternative methods of delivering thermal energy for treatment are also desirable for improving and diversifying treatment methods.

[0021] Some embodiments of the present disclosure describe a catheter comprising an elongate shaft and an ablation element disposed near the distal end of the elongate shaft, the ablation element including a tubular polymer member connected to the elongate shaft and a heating element disposed on the tubular polymer member and operably connected to an energy generator. In some embodiments, the heating element includes an electrically conductive trace defining a plurality of parallel segments disposed along the length of the tubular polymer member and one or more arcuate segments disposed between and connecting the parallel segments. The tubular polymer member can be made of a flexible material and, after electroplating or spray treatment, can maintain its flexibility to provide effective treatment at the target treatment site while minimizing potential unwanted damage to the vessel wall.

[0022] FIG. 1 is a schematic view of an exemplary ablation device 100 for treating chronic venous diseases, such as venous aneurysms, according to an embodiment of the present disclosure. The ablation device 100 includes an ablation catheter 102 including a handle 104, a elongate shaft 106 having a proximal end 108 and a distal end 112 terminating at a distal portion 110, and an ablation element 114 disposed in the vicinity of the distal end 112 of the elongate shaft 106. The shaft 106 is sized and configured such that the distal end 112 can be inserted into a target blood vessel. The ablation element 114 is configured to supply ablation energy (e.g., high-frequency energy, thermal energy) to the wall of the target blood vessel.

[0023] The ablation device 100 may include an energy generator 116 that is electrically coupled to the handle 104 via a connector 118 and is configured to generate energy by supplying an electrical signal (e.g., a current, a high-frequency alternating current). A controller 120 is operably connected to the energy generator 116 and controls the generation of the electrical signal. The controller 120 may be implemented using firmware, integrated circuits, and / or software modules that interact with each other or are combined together. For example, the controller 120 may include a memory 122 that stores computer-readable instructions / codes 124 for execution by a processor 126 (e.g., a microprocessor) to implement aspects of the method embodiments described herein.

[0024] According to some embodiments, the ablation element 114 employs structural features and / or components to improve the clinical performance of the ablation catheter 102 and enhance manufacturability. In some embodiments, the ablation element 114 can include a tubular polymer member connected to the elongate shaft 106 and a heating element disposed on the tubular polymer member and operably connected to the energy generator 116. In some embodiments, as described in more detail herein, the heating element includes an electrically conductive trace defining a plurality of parallel segments disposed along the length of the tubular polymer member and one or more arcuate segments disposed between and connecting the parallel segments.

[0025] In some embodiments, the controller 120 can be configured to communicate with the various components of the device 100 and generate a graphical user interface (GUI) displayed via the display 128. The controller 120 can include any type of computing device suitable for implementing the embodiments of the present disclosure. Examples of computing devices include workstations, servers, laptops, portable devices, desktops, tablet computers, handheld devices, and dedicated or general-purpose computing devices such as general-purpose graphics processing units (GPGPUs), all of which are contemplated within the scope of FIG. 1 with reference to the various components of the device 100.

[0026] In some embodiments, the controller 120 includes a bus that directly and / or indirectly couples devices such as a processor, memory, input / output (I / O) ports, I / O components, and a power supply. Any number of additional components, different components, and / or combinations of components may also be included in the computing device. The bus represents one or more buses (such as an address bus, a data bus, or a combination thereof). Similarly, in some embodiments, the computing device may include multiple processors, multiple memory components, multiple I / O ports, multiple I / O components, and / or multiple power supplies. Additionally, any number of these components, or combinations thereof, may be distributed and / or replicated across multiple computing devices.

[0027] In some embodiments, the memory 122 includes computer-readable media in the form of volatile and / or non-volatile memory, temporary storage media and / or non-temporary storage media, and can be removable, non-removable, or a combination thereof. Examples of media include random access memory (RAM), read only memory (ROM), electrically erasable programmable read only memory (EEPROM), flash memory, optical media or holographic media, magnetic cassettes, magnetic tapes, magnetic disk storage devices or other magnetic storage devices, data transmission, and / or any other media that can be used to store information and can be accessed by a computing device such as, for example, quantum state memory, and / or the like. In some embodiments, the memory 122 stores computer-executable instructions for causing a processor (such as the controller 120) to implement aspects of the embodiments of the system components described herein and / or to execute aspects of the embodiments of the methods and procedures described herein.

[0028] Computer-executable instructions 124 may include, for example, computer code, machine-usable instructions, and program components executable by one or more processors associated with a computing device, such as. Program components can be programmed using any number of different programming environments, including various languages, development kits, frameworks, and / or the like. Some or all of the functions contemplated herein can also or alternatively be implemented in hardware and / or firmware.

[0029] In some embodiments, memory 122 may include a data repository implemented using any one of the configurations described below. The data repository can include random access memory, flat files, XML files, and / or one or more database management systems (DBMSs) running on one or more database servers or data centers. The database management system can be a relational (RDBMS), hierarchical (HDBMS), multidimensional (MDBMS), object-oriented (ODBMS or OODBMS), or object-relational (ORDBMS) database management system, among others. The data repository can be, for example, a single relational database. In some cases, the data repository can include multiple databases that can exchange and aggregate data by means of a data integration process or software application. In an exemplary embodiment, at least a portion of the data repository can be hosted in a cloud data center. In some cases, the data repository can be hosted on a single computer, server, storage device, cloud server, or the like. In some other cases, the data repository can be hosted on a series of network-connected computers, servers, or devices. In some cases, the data repository can be hosted on a tiered data storage device including local, regional, and central.

[0030] The various components of device 100 can communicate via a communication interface, such as a wired or wireless interface, or be coupled to the communication interface. The communication interface includes, but is not limited to, wired or wireless short - and long - distance communication interfaces. For the wired interface, cables, umbilicals, and the like can be used. The short - distance communication interface can be an interface compliant with known communication standards such as, for example, a local area network (LAN), the Bluetooth® standard, the IEEE702 standard (e.g., IEEE702.11), ZigBee® or a similar specification (e.g., based on the IEEE702.15.4 standard), or other public or proprietary wireless protocols. The long - distance communication interface can be, for example, a wide area network (WAN), a cellular network interface, a satellite communication interface, etc. The communication interface can be within a private computer network such as an intranet or on a public computer network such as the Internet.

[0031] FIG. 2A is a schematic diagram of an exemplary ablation catheter 200 including a connector 218 (similar to connector 118 as shown in FIG. 1) for treating chronic venous diseases, such as varicose veins. FIG. 2B is a cross - sectional view of the connector 218 of the exemplary ablation catheter 200 along the cross - section indication line 2B - 2B of FIG. 2A according to an embodiment of the present disclosure.

[0032] As shown, the ablation catheter 200 includes a handle 204, an elongate shaft 206 having a distal end portion 210 that terminates at a proximal end 208 and a distal end 212, and an ablation element 214 disposed in the vicinity of the distal end 212 of the elongate shaft 206. The shaft 206 is sized and configured such that the distal end 212 can be inserted into a target blood vessel. The ablation element 214 is configured to supply ablation energy (e.g., high - frequency energy, thermal energy) to the wall of the target blood vessel.

[0033] In some embodiments, the connector 218 includes pins 242 of different sizes (e.g., including pins 242a, 242b) and pins 244 (e.g., including pins 244a, 244b). The pins 242 are relatively smaller than the pins 244 and are configured to transmit electrical signals (e.g., the electrical signals generated by the energy generator 116 of FIG. 1). Exemplary electrical signals may include thermocouple signals or pressure signals. The pins 244 are relatively larger compared to the pins 242 and may be configured to pass an electric current from an energy generator (e.g., the energy generator 116 of FIG. 1) to generate heat on the ablation element 214. One of the pins 244 may be used as a pin connected to ground (i.e., a ground pin). In some embodiments where the heating element includes a plurality of heating segments (e.g., a plurality of segments that can be individually controlled and / or addressed), the ground pin may be used as a common ground pin by the plurality of heating segments.

[0034] FIG. 3A is a schematic front view of the distal end portion 300 of an ablation catheter, and FIG. 3B is a partial enlarged view of the distal end portion 300 of the ablation catheter as shown by box 3B in FIG. 3A according to an embodiment of the present disclosure. As shown, the distal end portion 300 terminates at a distal end 304 and includes a portion of an elongate shaft 302 that defines a longitudinal axis 303 and an ablation element 306 disposed in the vicinity of the distal end 304 of the elongate shaft 302. The shaft 302 and the ablation element 306 are sized and configured such that the distal end 304 can be inserted into a target blood vessel.

[0035] The ablation element 306 includes a tubular polymer member 308 connected to the elongate shaft 302 and a heating element 310 disposed on the tubular polymer member 308 and operatively connected to an energy generator (e.g., the energy generator 116 in FIG. 1). In some embodiments, the heating element 310 includes an electrically conductive trace 312 that defines a plurality of parallel segments 314 disposed along the length of the tubular polymer member 308 and arcuate segments disposed between and connecting the parallel segments 314.

[0036] The tubular polymer member 308 enhances the flexibility of the distal portion 300 of the ablation catheter and minimizes potential undesirable damage to the vessel wall during the procedure. Since veins can be tortuous due to chronic venous disease, it is not easy for the operator to insert the distal end portion 300 of the ablation catheter into the target vein. If the catheter is too rigid, it may become increasingly difficult to position the ablation element 306 on the distal end portion 300 at a specific treatment site. As the flexibility of the catheter increases, it becomes easier for the distal end portion 300 to pass through the tortuous vein and reach the target treatment site, and the surgical time can also be shortened. The diameter, thickness, and material of the tubular polymer member 308 can be adjusted to further enhance the flexibility of the distal portion 300 of the ablation catheter.

[0037] A temperature sensor (not shown) can be disposed in the space between each of the plurality of parallel segments. Based on the measured sensor signal indicating the temperature from the temperature sensor, a controller (e.g., the energy controller 120 of FIG. 1) or a physician can selectively adjust the power supply to the heating element 310, and thus regulate the heat delivered to the target blood vessel. One or more pressure sensors (not shown) can be disposed proximate to the heating element 310 to measure a signal indicative of the pressure applied to the heating element 310 through the target tissue (e.g., the target vessel wall). In some embodiments, a plurality of pressure sensors (e.g., three sensors, four sensors, six sensors) are circumferentially disposed around the heating element (e.g., two adjacent pressure sensors are offset from each other by a certain angle in the projection view).

[0038] In some embodiments, the plurality of pressure sensors includes at least one selected from the group consisting of a piezoelectric pressure sensor, a capacitive pressure sensor, an inductive pressure sensor, a strain gauge pressure sensor, and a potentiometric pressure sensor. According to some embodiments, during the procedure, the heating element 310 is controlled to supply ablation energy when an output signal indicative of the pressure generated by at least one of the plurality of pressure sensors is greater than a predetermined threshold. In certain embodiments, the heating element 310 is controlled to supply ablation energy when an output signal indicative of the pressure generated by some or all of the plurality of pressure sensors is greater than a predetermined threshold.

[0039] In some embodiments, as illustrated, the electrically conductive trace 312 includes a plurality of arcuate segments 316 and has a meandering shape formed by the plurality of parallel segments 314 and the plurality of arcuate segments 316. In an embodiment, the plurality of parallel segments 314 can be spaced apart from each other longitudinally or circumferentially on the tubular polymer member 308, and one of the plurality of arcuate segments 316 is disposed between adjacent parallel segments 314 and can connect the adjacent parallel segments 314. In some embodiments, the plurality of parallel segments 314 are equally spaced apart.

[0040] In an exemplary embodiment, as shown in FIGS. 3A - 3B, the plurality of parallel segments 314 extend longitudinally along the longitudinal axis 303 on the tubular polymer member 308 and are spaced apart from each other circumferentially. In a specific example, all of the two adjacent parallel segments connected by the arcuate segment 316a proximate to the distal end 304 have the same spacing d1. In some examples, all of the two adjacent parallel segments connected by the arcuate segment 316b further away from the distal end 304 have the same spacing d2. In a specific example, the spacing d1 is equal to the spacing d2. In some examples, the spacing d1 is different from the spacing d2. In an embodiment, the spacings d1 and d2 between the parallel segments can be decreased to increase the distribution density of the heating elements for obtaining higher thermal efficiency during treatment. In an embodiment, the spacings d1 and d2 between the parallel segments can be increased to enhance the flexibility of the distal end portion 300 of the ablation catheter according to the requirements of a specific treatment.

[0041] In some embodiments, the heating element 310 is disposed on the outer surface of the tubular polymer member 308. In an embodiment, the heating element 310 can include a plurality of segments disposed on the inner surface of the tubular polymer member 308.

[0042] During the procedure, the electrically conductive trace 312 receives a current that travels in the direction indicated by arrow 318 supplied by an energy generator (e.g., energy generator 116 of FIG. 1). After the current passes through the plurality of parallel segments 314 and the arcuate segment 316, the current returns in a direction 320 opposite to the original direction 318. Similarly, due to the meandering shape, during the procedure, a current in the opposite direction flows for every two adjacent parallel segments. The magnetic field generated by the current is canceled out by the current in the opposite direction. Since the inductance can be substantially eliminated by canceling out the magnetic field, most of the generated energy is converted into thermal energy rather than electromagnetic energy, and thus the procedure is performed more energy efficiently.

[0043] In an exemplary embodiment, as shown, for example, in FIG. 3A, one or more pairs of parallel segments 314 are disposed on the outer surface of the tubular polymer member 308 and are connected end to end by the arcuate segment 316, and two of the ends are connected to wires that connect the heating element 310 to a generator (e.g., generator 116 of FIG. 1) via a catheter handle (e.g., handle 104 of FIG. 1) and a cable (e.g., cable 105 of FIG. 1). In an embodiment, the tubular polymer member 308 is sized to be inserted into the target vasculature while providing ablation efficiency (e.g., sufficient width, sufficient length, etc.). In some embodiments, the length (L) of the tubular polymer member 308 can be a length of about 3 centimeters to about 7 centimeters. In some embodiments, the diameter (d) of the tubular polymer member 308 can be from about 1.5 millimeters to about 18 millimeters. In an exemplary embodiment, the diameter (d) of the tubular polymer member 308 can be from about 1.5 millimeters to about 1.8 millimeters. In certain embodiments, the length of the tubular polymer member 308 is greater than 2 centimeters. In some embodiments, the length of the tubular polymer member 308 is less than 10 centimeters. In certain embodiments, the diameter of the tubular polymer member 308 is greater than 1 millimeter. In some embodiments, the diameter of the tubular polymer member 308 is less than 20 millimeters.

[0044] In some embodiments, the heating element 310 includes a Ni-Cr alloy or a carbon film. The Ni-Cr alloy or carbon film can be formed on the tubular polymer member 308 by electroplating or spray treatment. In some embodiments, the film formed by electroplating or spray treatment can be from about 0.05 μm to about 0.3 μm. In an exemplary embodiment, the film formed by electroplating or spray treatment can be from about 0.1 μm to about 0.2 μm.

[0045] Compared to a heating element that uses a coil (e.g., a resistance wire), one advantage of forming a film by electroplating or metal spray treatment is to enhance the consistency of the manufacturing method to achieve a more uniform and / or smoother heating surface. The film can be formed by electroplating or metal spray treatment, or can be manufactured using any method commonly used for manufacturing flexible circuits as understood by those skilled in the art. The film can be manufactured using a method similar to that of a flexible circuit, but in some embodiments, the film includes a material having a higher electrical resistance than typical materials used for flexible circuits. In an embodiment, the heating element 310 including a film formed by spray or electroplating treatment is operably connected to an energy generator (e.g., the generator 116 of FIG. 1) and is configured to generate thermal energy in response to receiving an electrical signal from the energy generator.

[0046] Figure 4A is a schematic perspective front view of the distal end portion 400 of an ablation catheter according to an embodiment of the present disclosure, Figure 4B is a partial enlarged view of the distal end portion 400 of the ablation catheter shown by box 4B in Figure 4A, and Figure 4C is a sectional view of the partial enlarged view shown in Figure 4B of the distal end portion 400 of the ablation catheter. As shown, the distal end portion 400 terminates at a distal end 404 and includes a portion of an elongate shaft 402 that defines a longitudinal axis 403, and an ablation element 406 disposed in the vicinity of the distal end 404 of the elongate shaft 402. The shaft 402 and the ablation element 406 are sized and configured such that the distal end 404 can be inserted into a target blood vessel.

[0047] The ablation element 406 includes a tubular polymer member 408 connected to the elongate shaft 402, and a heating element 410 disposed on the tubular polymer member 408 and operatively connected to an energy generator (e.g., the energy generator 116 of FIG. 1). In some embodiments, the heating element 410 includes an electrically conductive trace 412 that defines a plurality of parallel segments 414 disposed along the length of the tubular polymer member 408, and one or more arcuate segments disposed between the parallel segments 414 and connecting the parallel segments 414.

[0048] The tubular polymer member 408 enhances the flexibility of the distal portion 400 of the ablation catheter and minimizes potential undesirable damage to the blood vessel wall during the procedure. A temperature sensor (not shown) can be disposed in the space between each of the plurality of parallel segments. Based on a measured signal indicative of the temperature by the temperature sensor, a controller (e.g., the energy controller 120 of FIG. 1) or a physician can adjust the power supply to the heating element 410 and thus adjust the thermal ablation energy delivered to the target blood vessel.

[0049] In some embodiments, as shown, the electrically conductive trace 412 includes a plurality of arch-shaped segments 416 and has a meandering shape formed by the plurality of parallel segments 414 and the plurality of arch-shaped segments 416.

[0050] In an embodiment, the plurality of parallel segments 414 can be spaced apart from each other longitudinally or circumferentially on the tubular polymer member 408, and one of the plurality of arch-shaped segments 416 is disposed between adjacent parallel segments 414 and can connect the adjacent parallel segments 414. In some embodiments, each of the plurality of parallel segments 414 is equally spaced. In an exemplary embodiment, as shown in FIGS. 4A-4C for example, the plurality of parallel segments 414 extend circumferentially around the tubular polymer member 408 and are spaced apart from each other longitudinally along the longitudinal axis 403.

[0051] In some embodiments, the heating element 410a is disposed on the outer surface of the tubular polymer member 408. In a particular embodiment, as shown in FIGS. 4A-4C for example, the heating element 410b can include a plurality of segments disposed on the inner surface of the tubular polymer member 408. In an exemplary embodiment, the heating element 410 includes both the heating elements 410a and 410b disposed on the outer surface and the inner surface of the tubular polymer member 408, respectively.

[0052] During the procedure, the electrically conductive trace 412 receives a current that travels in the direction indicated by arrow 418 supplied by an energy generator (e.g., energy generator 116 of FIG. 1). After the current passes through the plurality of parallel segments 414 and the arcuate segment 416, the current returns in a direction 420 opposite to the initial direction 418. Similarly, due to the meandering shape, during the procedure, in each adjacent parallel segment 414, a current flows in the segment in the opposite direction. The opposing currents cancel out the magnetic field generated by the current, and thus the procedure is performed more energy efficiently. In some embodiments, the heating element 410b disposed on the inner surface of the tubular polymer member 408 passes a current in a direction opposite to the current passing through the heating element 410a disposed on the outer surface of the tubular polymer member 408, further canceling out the magnetic field generated by the current during the procedure. In embodiments where the heating element 410b passes a current in a direction opposite to the current passing through the heating element 410a, the heating element 410a functions as a therapeutically active heating element, and the heating element 410b can function as a therapeutically passive heating element to counteract the electric field generated by the current passing through the therapeutically active heating element 410a. Since the inductance can be substantially eliminated by canceling the magnetic field, most of the generated energy is converted into thermal energy rather than electromagnetic energy, and thus the procedure is performed more energy efficiently.

[0053] In some embodiments, the heating element 410 comprises a Ni—Cr alloy or a carbon film. The Ni—Cr alloy or carbon film may be formed on the tubular polymer member 408 by electroplating or spray treatment.

[0054] FIG. 5 is a schematic view of a distal end portion of an ablation catheter according to an embodiment of the present disclosure. As shown, the distal end portion 500 includes a portion of an elongate shaft 502 that terminates at a distal end 504 and defines a longitudinal axis 503, and an ablation element 506 disposed in the vicinity of the distal end 504 of the elongate shaft 502. The shaft 502 and the ablation element 506 are sized and configured such that the distal end 504 can be inserted into a target blood vessel.

[0055] The ablation element 506 includes a tubular polymer member 508 connected to the elongate shaft 502, and a heating element 510 disposed on the tubular polymer member 508 and operatively connected to an energy generator (e.g., the energy generator 116 of FIG. 1). In some embodiments, the heating element 510 includes an electrically conductive trace 512 that defines a plurality of parallel segments 514 disposed along the length of the tubular polymer member 508, and arcuate segments 516 disposed between two adjacent parallel segments of the plurality of parallel segments 514 and connecting the two adjacent parallel segments. The tubular polymer member 508 enhances the flexibility of the distal portion 500 of the ablation catheter and minimizes potential undesirable damage to the blood vessel wall during the procedure. A temperature sensor (not shown) can be disposed in the space between each of the plurality of parallel segments 514. Based on a measured signal indicative of the temperature from the temperature sensor, a controller (e.g., the energy controller 120 of FIG. 1) or a physician can selectively adjust the power supply to the heating element 510, and thus adjust the heat delivered to the target blood vessel. In some embodiments, the power supply to the heating element 510 can heat the heating element 510 to about 80° C. to about 140° C. to treat an aneurysm. In some embodiments, the power supply to the heating element 510 can heat the heating element 510 to about 100° C. to about 130° C. to treat an aneurysm. In some embodiments, the power supply to the heating element 510 can heat the heating element 510 to up to about 120° C. to treat an aneurysm.

[0056] In an exemplary embodiment, as shown in FIG. 5, a plurality of parallel segments 514 of the conductive trace 512 are helically wound around the tubular polymer member 508. In some embodiments, the conductive trace 512 includes two portions 512a and 512b that are parallel and form a pair of patterns. In a particular example, the spacing between the pair of portions is d3. In some examples, the spacing between two adjacent pairs of portions is d4. In a particular example, the spacing d3 is equal to the spacing d4. In some examples, the spacing d3 is different from the spacing d4.

[0057] In some embodiments, the heating element 510 is disposed on the outer surface of the tubular polymer member 508. In one embodiment, the heating element 510 may include a plurality of segments disposed on the inner surface of the tubular polymer member 508. In some embodiments, a heating element disposed on the inner surface (not shown) of the tubular polymer member 508 passes current in a direction opposite to the current passing through the heating element 510 disposed on the outer surface of the tubular polymer member 508, canceling out the magnetic field generated by the current passing through each of the heating elements 510 during treatment. In some embodiments, the heating element 510 includes a Ni—Cr alloy or a carbon film. The Ni—Cr alloy or carbon film may be formed on the tubular polymer member 508 by electroplating or spraying.

[0058] FIGS. 6A-6B are schematic views of a portion of an ablation catheter for use within a target vessel of a patient for the treatment of an aneurysm, according to an embodiment of the present disclosure. In some embodiments, during an intravenous thermal ablation procedure, an introducer sheath can be placed into a patient's target vein using ultrasonic guidance and standard vascular techniques. An ablation catheter (e.g., ablation catheter 102 in FIG. 1) can then be inserted through the introducer sheath into the target vein. In some situations, under ultrasonic guidance, an infiltration anesthetic solution or saline can be injected into the target vein segment to function as a heat sink to protect the tissue from thermal damage and to improve the thermal conductivity between the wall of the target vein and the ablation catheter.

[0059] As shown in FIG. 6A, the distal end portion 600 of an ablation catheter (e.g., ablation catheter 102 of FIG. 1) is disposed within the target vessel 602a. The ablation catheter can be introduced and positioned by an introducer sheath using ultrasonic guidance. As will be understood by those skilled in the art, any standard vascular technique can be used here to introduce and position the distal end portion 600 of the ablation catheter within the target vein segment. The distal end portion 600 can include an ablation element 606 having a tubular polymer member 608 and a heating element 610 disposed on the tubular polymer member 608 and operably connected to an energy generator (e.g., energy generator 116 of FIG. 1).

[0060] In some embodiments, during the procedure, an electric current can be applied to the heating element 610 by a generator (e.g., energy generator 116 of FIG. 1), and a segment of the target vessel 602a to be treated adjacent to the heating element 610 closes as shown as 602b in FIG. 6B when the heating element 610 is heated. The generator can include a high-frequency generator that generates a high-frequency electric current to heat the heating element 610. In some implementations, the ablation catheter can include a temperature sensor disposed along the length of the catheter shaft, and the power supply to the heating element 610 can be automatically adjusted by a controller (e.g., controller 120 of FIG. 1) based on the temperature measured by the temperature sensor or a signal indicative of the temperature.

[0061] The segment of the target blood vessel 602a to be treated adjacent to the heating element 610 will close (e.g., contract, decrease in diameter) as the heating element 610 is heated, as shown as 602b in FIG. 6B. During the treatment, external pressure can be applied as needed. After a particular section has been treated (i.e., the section of the vein has closed), the catheter can be moved toward the venous access, as indicated by arrow 616, and this process is repeated until the entire vein is occluded. The catheter and introducer sheath can then be removed after the treatment has been performed. In some cases, the diameter of the ablation element 606 is smaller than the diameter of the blood vessel 602a, and during the treatment, the ablation element 606 can be moved close to the vessel wall.

[0062] In Example 16, a device for treating a venous aneurysm includes an energy generator configured to generate an electrical signal, a controller operably connected to the energy generator and configured to control the generation of the electrical signal, and a catheter connected to the energy generator. The catheter includes an elongate shaft having a proximal end and a distal end, the elongate shaft sized and configured such that the distal end can be inserted into a target blood vessel, and an ablation element disposed in the vicinity of the distal end of the elongate shaft. In some embodiments, the ablation element includes a tubular polymer member connected to the elongate shaft and a heating element disposed on the tubular polymer member, the heating element comprising an electrically conductive trace defining a plurality of parallel segments disposed along the length of the tubular polymer member and one or more arch-shaped segments, at least one of the one or more arch-shaped segments being disposed between two adjacent parallel segments of the plurality of parallel segments and connecting the two adjacent parallel segments, the electrically conductive trace being operably connected to the energy generator and configured to generate ablation energy in response to receipt of an electrical signal from the energy generator.

[0063] In Example 17, in the device of Example 13, the electrically conductive trace has a meandering shape formed by a plurality of parallel segments and one or more arched segments, and the plurality of parallel segments are spaced apart from each other longitudinally or circumferentially on the tubular polymer member.

[0064] In Example 18, in the device of Example 14, the plurality of parallel segments extend longitudinally along the tubular polymer member and are spaced apart from each other circumferentially. In Example 19, in the device of Example 14, the plurality of parallel segments extend circumferentially around the tubular polymer member and are spaced apart from each other longitudinally.

[0065] In Example 20, in the device of Example 13, the plurality of parallel segments are spirally wound around the tubular polymer member. In Example 21, in any of the devices of Examples 13 to 17, the heating element is disposed on the outer surface of the tubular polymer member.

[0066] In Example 22, in any of the devices of Examples 13 to 17, at least a part of the heating element is disposed on the inner surface of the tubular polymer member. In Example 23, in any of the devices of Examples 13 to 19, the heating element contains a Ni-Cr alloy.

[0067] In Example 24, in any of the devices of Examples 13 to 19, the heating element contains a carbon film. In Example 25, in any of the devices of Examples 13 to 21, the plurality of parallel segments are equally spaced apart.

[0068] In Example 26, in the device of Example 20, the Ni-Cr alloy is formed on the tubular polymer member by electroplating or spraying. In Example 27, in the device of Example 21, the carbon film is formed on the tubular polymer member by electroplating or spraying.

[0069] As used herein, the terms "about" and "approximately" are used interchangeably with respect to measurements (e.g., dimensions, characteristics, attributes, components, etc.) and ranges thereof, specifically with respect to tangible things (e.g., products, inventories, etc.) and / or intangible things (e.g., data, electronic currency representations, accounts, information, ratios of things (e.g., percentages, fractions), calculations, data models, dynamic system models, algorithms, parameters, etc.). These "about" and "approximately" include the recited measurement values and also measurement values that are reasonably close to the recited measurement values, taking into account measurement errors, differences in calibration of measurement instruments and manufacturing equipment, human errors in reading and / or setting measurement values, adjustments for optimization of performance and structural parameters considering other measurement values (e.g., measurement values related to other things), specific implementation scenarios, human, computing device, mechanical operation, setting, inaccurate adjustment and / or operation of measurement values, system tolerances, control loops, machine learning, predictable variations (e.g., statistically negligible variations, chaotic variations, system and / or model instabilities, etc.), preferences and / or the like, and include minor differences that can be readily judged.

[0070] Exemplary methods may be represented by one or more drawings (e.g., flow diagrams, communication flows, etc.), but the drawings should not be construed as implying requirements for the various steps disclosed herein or a particular order between steps. However, some specific embodiments may require specific steps and / or a specific order between specific steps, as may be explicitly described herein and / or understood from the nature of the steps themselves (e.g., the execution of some steps may depend on the result of a previous step). Further, a "set", "subset", or "group" of items (e.g., inputs, algorithms, data values, etc.) may include one or more items, and similarly, a subset or subgroup of items may include one or more items. "Plurality" means two or more.

[0071] Without departing from the scope of the present invention, various modifications and additions can be made to the exemplary embodiments described. For example, although the above-described embodiments refer to specific features, the scope of the present invention also includes embodiments having different combinations of features and embodiments that do not include all of the described features. Accordingly, the scope of the present invention is intended to embrace all such alternative, modified, and variant forms included in the claims, together with all of their equivalents.

Claims

**Claim 1** A device for treating an aneurysm, comprising a catheter, the catheter comprising a long shaft having a proximal end and a distal end, sized and configured such that the distal end can be inserted into a target blood vessel, the long shaft; and an ablation element disposed in the vicinity of the distal end of the long shaft, wherein the ablation element comprises a tubular polymer member connected to the long shaft; and a heating element disposed on the tubular polymer member, the heating element comprising an electrically conductive trace defining a plurality of parallel segments disposed along the length of the tubular polymer member and one or more arcuate segments, at least one of the one or more arcuate segments being disposed between two adjacent parallel segments of the plurality of parallel segments and connecting the two adjacent parallel segments. A device. **Claim 2** The device according to claim 1, wherein the electrically conductive trace has a meandering shape formed by the plurality of parallel segments and the one or more arcuate segments, and the plurality of parallel segments are spaced apart from each other in a longitudinal direction or a circumferential direction on the tubular polymer member. **Claim 3** The device according to claim 2, wherein the plurality of parallel segments extend longitudinally along the tubular polymer member and are spaced apart from each other in a circumferential direction. **Claim 4** The device according to claim 2, wherein the plurality of parallel segments extend circumferentially around the tubular polymer member and are spaced apart from each other in a longitudinal direction. **Claim 5** The device according to claim 1, wherein the plurality of parallel segments are spirally wound around the tubular polymer member. **Claim 6** The device according to any one of claims 1 to 5, wherein the heating element is disposed on the outer surface of the tubular polymer member. **Claim 7** The device according to any one of claims 1 to 5, wherein at least a part of the heating element is disposed on the inner surface of the tubular polymer member. **Claim 8** The device according to any one of claims 1 to 7, wherein the heating element comprises a Ni—Cr alloy. **Claim 9** The device according to any one of claims 1 to 7, wherein the heating element comprises a carbon film. **Claim 10** The device according to any one of claims 1 to 9, wherein the plurality of parallel segments are spaced apart at equal intervals.

11. The device according to claim 8, wherein the Ni—Cr alloy is formed on the tubular polymer member by electroplating or spraying.

12. The device according to claim 9, wherein the carbon film is formed on the tubular polymer member by electroplating or spraying.

13. A system for treating an aneurysm, comprising: the device according to any one of claims 1 to 12; an energy generator connected to the elongated catheter and configured to generate an electrical signal; a controller operably connected to the energy generator and configured to control the generation of the electrical signal.

14. The system according to claim 13, wherein the heating element is electrically connected to the energy generator.

15. The system according to claim 13, wherein the device includes one or more pressure sensors configured to generate an output signal indicating an applied pressure, and the controller is configured to adjust the electrical signal supplied to the heating element based on the output signal.

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