CN118984682A

CN118984682A - Dual Focused and Linear Pulsed Field Ablation (PFA) Catheters

Info

Publication number: CN118984682A
Application number: CN202380032005.XA
Authority: CN
Inventors: M·T·斯图尔特; B·T·霍华德
Original assignee: Medtronic Inc
Current assignee: Medtronic Inc
Priority date: 2022-04-01
Filing date: 2023-03-20
Publication date: 2024-11-19
Also published as: EP4504083A1; WO2023192056A1

Abstract

An example method for performing pulsed field ablation (PFA) includes: at a first time and by a controller connected to a specific catheter, determining to perform PFA using a linear PFA mode; in response to determining to use the linear PFA mode, by the controller and outputting energy to an electrode of the specific catheter so that the electrode produces a field having a geometry that is linear along an active portion of the specific catheter; at a second time and by the controller, determining to perform PFA using a focused PFA mode; and in response to determining to use the focused PFA mode, by the controller and outputting energy to the electrode of the specific catheter so that the electrode produces a field having a geometry that is focused at the tip of the specific catheter.

Description

Dual focus and linear Pulsed Field Ablation (PFA) catheter

The present application claims the benefit of U.S. provisional patent application 63/326,513 filed on 1 month 2022 and U.S. patent application 18/183,546 filed on 14 months 2023, 4, the disclosures of which are incorporated herein by reference in their entireties.

Technical Field

The present technology relates to ablation catheters. In particular, various examples of the present technology relate to ablation catheters for performing Pulsed Field Ablation (PFA).

Background

Tissue ablation is a medical procedure commonly used to treat conditions such as cardiac arrhythmias, including atrial fibrillation. For treating cardiac arrhythmias, ablation may be performed to modify the tissue so as to stop abnormal electrical propagation and/or to interrupt abnormal electrical conduction through the heart tissue. Although thermal ablation techniques such as cryoablation and Radio Frequency (RF) ablation are often used, non-thermal techniques such as Pulsed Field Ablation (PFA) may also be used.

Pulsed field ablation involves the application of a short Pulsed Electric Field (PEF) that can reversibly or irreversibly destabilize cell membranes by electroosmosis, but does not generally affect the structural integrity of tissue components, including the extracellular matrix of the cell-free heart. The nature of PFA allows for very short therapeutic energy delivery, on the order of tens of milliseconds. Furthermore, PFA may not cause collateral damage to non-target tissue as frequently or as severely as thermal ablation techniques.

Disclosure of Invention

The present technology relates to devices, systems, and methods for performing Pulsed Field Ablation (PFA) in multiple modes using a single catheter. PFA may be executed in a variety of modes, including a linear mode and a focus mode. Linear mode PFA may result in a linear, relatively uniform field geometry along the active portion of the conduit (e.g., the cathode and anode may alternate along the conduit). On the other hand, focus mode PFA may result in a field geometry focused at the tip of the catheter (e.g., the tip of the catheter may be the cathode while the other portion of the catheter may be the anode, or vice versa). Generally, linear mode PFA may produce lesions of greater length than width, while focused mode PFA may produce lesions of greater width than length. In some examples, a practitioner desiring to use both linear mode PFA and focus mode PFA may have to physically switch between different catheters. For example, to switch from linear mode PFA to focus mode PFA, the surgeon may have to remove the linear mode catheter and insert the focus mode catheter. It may be undesirable to have to physically switch catheters when using different PFA modes.

In accordance with one or more aspects of the present disclosure, a single catheter may be configured to perform PFA in both a linear mode and a focus mode. For example, the catheter may include a plurality of electrodes that are independently controllable and are sufficient in number to perform both the linear mode and the focus mode. To operate the catheter in a focus mode, the controller may output energy to the electrodes of the catheter to cause the electrodes to generate a field having a geometry focused at the tip of the catheter. For example, the controller may cause one or more electrodes positioned proximal to the tip of the catheter to operate as a cathode and a plurality of electrodes positioned further distal to the tip to operate as an anode. To operate the catheter in the linear mode, the controller may output energy to the electrodes of the catheter to cause the electrodes to generate a field having a geometry that is relatively uniform linearly along the active portion of the catheter. For example, the controller may cause the electrodes to form alternating cathodes and anodes.

Although a catheter capable of performing both linear PFA and focused PFA may be more complex and/or more expensive to manufacture than a catheter capable of performing only one of linear PFA and focused PFA, the catheter of the present disclosure may provide several advantages. For example, the catheter of the present disclosure may enable a surgeon to switch between linear PFA and focused PFA without removing the catheter and reinserting the catheter.

In one example, a catheter for performing Pulsed Field Ablation (PFA) includes: an elongated structure defining a longitudinal axis; a plurality of electrodes carried on a distal portion of the elongate structure, the plurality of electrodes comprising: a tip electrode positioned at a distal tip of the elongated structure; a tip ring electrode adjacent to the tip electrode; a pair of ring electrodes; and one or more additional electrodes, wherein the pair of ring electrodes is disposed longitudinally along the elongated structure between the tip ring electrode and the one or more additional electrodes.

In another example, a method for performing Pulsed Field Ablation (PFA) includes: determining, at a first time and by a controller connected to the particular catheter, to perform PFA using a linear PFA mode; responsive to determining to use the linear PFA mode, outputting, by the controller and to an electrode of the particular catheter, energy to cause the electrode to generate a field having a geometry that is linear along an active portion of the particular catheter; performing PFA using a focused PFA mode at a second time and determined by the controller; in response to determining to use the focused PFA mode, energy is output by the controller and to the electrode of the particular catheter to cause the electrode to generate a field having a geometry focused at the tip of the particular catheter.

The details of one or more aspects of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the technology described in this disclosure will be apparent from the description and drawings, and from the claims.

Drawings

Fig. 1 is a conceptual diagram illustrating an example system for delivering Pulsed Field Ablation (PFA) in accordance with one or more aspects of the present disclosure.

Fig. 2A and 2B are conceptual diagrams illustrating example linear operations and focusing operations of a catheter according to one or more aspects of the present disclosure.

Fig. 2C and 2D are conceptual diagrams illustrating example fields generated by linear operation and focusing operation of a catheter in accordance with one or more aspects of the present disclosure.

Fig. 3A and 3B are conceptual diagrams illustrating example linear operations and focusing operations of a catheter according to one or more aspects of the present disclosure.

Fig. 3C and 3D are conceptual diagrams illustrating example fields generated by linear operation and focusing operation of a catheter in accordance with one or more aspects of the present disclosure.

Fig. 4 is a conceptual diagram illustrating an example focusing operation of a catheter in accordance with one or more aspects of the present disclosure.

Fig. 5 is a block diagram illustrating an example controller of a multi-mode PFA system in accordance with one or more aspects of the present disclosure.

Fig. 6 is a flow diagram illustrating an example technique for performing both linear PFA and focused PFA using a single catheter in accordance with one or more aspects of the present disclosure.

Detailed Description

Fig. 1 is a conceptual diagram illustrating an example system 100 for delivering Pulsed Field Ablation (PFA) including a catheter 102 and a controller 104. Generally, to deliver PFA, a medical practitioner (e.g., cardiologist, surgeon, etc.) can insert catheter 102 into a patient and cause controller 104 to deliver electroporation energy (e.g., pulsed field ablation energy) via catheter 102. Electroporation may be a phenomenon that causes a cell membrane to become "leaky" (i.e., permeable to molecules that the cell membrane may be impermeable or semi-permeable). Electroporation, which may also be referred to as electroosmosis, pulsed electric field treatment, nonthermal irreversible electroporation, high frequency irreversible electroporation, nanosecond electroporation, or nanoelectroporation, involves the application of high amplitude pulses to cause physiological modification (i.e., permeabilization) of cells of a tissue to which energy is applied. These pulses may be short (e.g., nanosecond, microsecond, or millisecond pulse width) in order to allow high voltages, high currents (e.g., 20 amps or more) to be applied without long duration current flow that might otherwise result in significant tissue heating and muscle stimulation. Pulsed electrical energy can induce the formation of microscopic defects, resulting in superpermeabilization of the cell membrane. Depending on the nature of the electrical pulse, the electroporated cells may survive (referred to as "reversible electroporation") or die (referred to as "irreversible electroporation" (IRE)) after electroporation. Reversible electroporation can be used to transfer agents (including genetic material and other macromolecules or small molecules) into target cells for a variety of purposes, including altering the action potential of cardiomyocytes.

Catheter 102 may include an elongated structure 112 carrying a plurality of electrodes 110A-110H (collectively, "electrodes 110"). Catheter 102 may generally include features that enable catheter 102 to be inserted into a patient and enable catheter 102 to navigate to a target treatment site. The elongate structure 112 may include a distal portion 106 and a proximal portion 108. The electrode 110 may be generally positioned at the distal portion 106, while the proximal portion 108 may be connected to the controller 104. The electrode 110 may have any suitable geometry. Example geometries of electrodes include, but are not necessarily limited to, circular (e.g., ring-shaped) electrodes, conformable electrodes, hoop-shaped electrodes, segmented electrodes (e.g., electrodes disposed at different circumferential locations around the lead, rather than continuous ring-shaped electrodes) and any combination thereof (e.g., ring-shaped electrodes and segmented electrodes). The electrodes 110 may be axially distributed along a longitudinal axis LA of the elongated structure 112.

The elongated structure 112 may include conductors configured to carry electrical signals between the electrodes 110 and the controller 104. In some examples, the elongated structure 112 may include separate conductors (e.g., separate control leads) for each of the electrodes 110. For example, in the example of fig. 1 where electrode 110 includes eight electrodes, elongate structure 112 may include eight separate conductors. In this manner, the elongated structure may enable each of the electrodes 110 to be driven with a different signal. In other examples, multiple ones of the electrodes 110 may share a common conductor. For example, electrodes 110C and 110D may be connected to the same (e.g., common) conductor. While such common conductor arrangements may reduce flexibility (e.g., because electrodes connected to the common conductor may be driven with the same signal), such arrangements may reduce manufacturing complexity and/or cost. Generally, the conductors may be referred to as control leads.

As shown in fig. 1, electrode 110 may comprise a tip electrode (e.g., electrode 110A), which may be a ring electrode having a "cap" covering at least a portion of the tip of elongated structure 112. In some examples, the tip electrode may be beveled or otherwise rounded (e.g., to enable catheter 102 to more easily pass through the anatomy of the patient). Electrode 110 may include a tip ring electrode (e.g., electrode 110B) adjacent to the tip electrode. The tip ring electrode may be separated from the tip electrode (axially along LA). The electrode 110 may include one or more ring electrode pairs. The ring electrode pair may include two adjacent closely spaced electrodes of the electrodes 110. For example, in the example of fig. 1, electrodes 110C and 110D may form a first annular electrode pair, electrodes 110E and 110F may form a second annular electrode pair, and electrodes 110G and 110H may form a third annular electrode pair. Generally, the first annular electrode pair (i.e., electrodes 110C and 110D) may be accompanied by one or more additional electrodes. The one or more additional electrodes may include any combination of ring electrode pairs and coil electrodes (e.g., electrodes comprising conductors that spiral around the elongated structure 112). Thus, electrode 110 may include a tip electrode 110A, a tip ring electrode 110B (e.g., adjacent to tip electrode 110A), electrodes 110C and 110D (e.g., a ring electrode pair), and one or more additional electrodes (e.g., ring electrode pairs 110E and 110F and ring electrode pairs 110G and 110H).

In the example of fig. 1, the electrode 110 is illustrated as having a larger diameter than the elongated structure 112. In some examples, one or more of the electrodes 110 may have a diameter substantially equal to the diameter of the elongated structure 112. For example, the electrodes 110 may be recessed within the elongated structure 112 such that the combination produces a relatively smooth outer surface.

The controller 104 may include an energy generator configured to provide electrical pulses to the electrodes 110 to perform an electroporation procedure on heart tissue or other tissue within the patient, such as kidney tissue, airway tissue, and organs or tissue within the heart space or pericardial space. For example, the energy generator may be configured and programmed to deliver a pulsed high voltage electric field suitable for achieving desired pulses, high voltage ablations (referred to as "pulsed field ablations" or "pulsed electric field ablations"), and/or pulsed radio frequency ablations. As a point of reference, the non-radiofrequency pulsed high voltage ablation effect of the present disclosure can be distinguished from DC current ablation and thermally induced ablation accompanying conventional RF techniques. For example, the bursts delivered by the energy generator may be delivered at a frequency of less than 30kHz, and in an exemplary configuration at a frequency of 1kHz (frequency below the frequency of the radio frequency treatment). The pulsed field energy according to the present disclosure may be sufficient to induce cell death so as to completely block abnormal conduction pathways along or through cardiac tissue, thereby disrupting the ability of the cardiac tissue so ablated to propagate or conduct cardiac depolarization waveforms and associated electrical signals. Additionally or alternatively, the energy generator may be configured and programmed to deliver RF energy suitable for achieving tissue ablation.

In accordance with one or more aspects of the present disclosure, catheter 102 may be configured to selectively perform PFA using a linear mode or a focus mode. For example, the electrodes 110 of the catheter 102 may include both electrodes configured to deliver PFA using a linear mode and electrodes configured to deliver PFA using a focused mode (some or all overlap between the electrodes may exist for different modes). The present disclosure provides several advantages by enabling a single catheter to perform both linear mode PFA and focus mode PFA. As one example, a practitioner may switch between linear lesion formation and focused lesion formation without having to remove the catheter. As another example, supply management may be simplified (e.g., because the number of catheter types may be reduced).

During an ablation procedure, a practitioner may desire to switch between linear lesion formation and focused lesion formation. To achieve such switching, the controller 104 may be configured to selectively operate the catheter 102 in a linear mode and a focus mode. The practitioner may adjust the settings of the controller 104 to either a linear mode or a focus mode. The controller 104 may operate the catheter 102 in a selected mode. For example, to operate catheter 102 in a focus mode, controller 104 may output energy to electrode 110 to cause electrode 110 to generate a field having a geometry focused at the tip of catheter 102 (e.g., focused at tip electrode 110A). Such focused field geometries may result in the formation of lesions proximal to the tip of the catheter 102. To operate the catheter 1002 in the linear mode, the controller 104 may output energy to the electrode 110 to cause the electrode 110 to generate a field having a geometry that is linear relatively uniform along the active portion of the catheter 102 (e.g., along a portion of the catheter 102 on which the electrode 110 is positioned). Such linear field geometries may result in foci forming longitudinally along the active portion of catheter 102.

As discussed above, to operate the catheter 102 in the focus mode, the controller 104 may output energy to the electrode 110 to cause the electrode 110 to generate a field having a geometry focused at the tip of the catheter 102. For example, the controller 104 may cause one or more electrodes positioned proximal to the tip of the catheter 102 (e.g., tip electrode 110A and tip ring electrode 110B) to operate as cathodes and a plurality of electrodes positioned more distal to the tip (e.g., ring electrodes 110C and 110D) to operate as anodes. In some examples, one or more of the cathode and/or anode may be formed from a single electrode. In some examples, one or more of the cathode and/or anode may be formed from a plurality of electrodes. For example, the electrodes of a ring electrode pair may be driven with the same signal such that the electrodes of the ring electrode pair act as a single cathode or a single anode.

In some examples, to facilitate functioning as a single anode or a single cathode, the electrodes of the ring electrode pair may be positioned closer to each other than to adjacent electrodes. For example, the distance between the electrodes of the first ring electrode pair (e.g., the distance along LA between electrodes 110C and 110D) may be less than the distance between the distal ring electrode and the tip ring electrode of the ring electrode pair (e.g., the distance along LA between electrodes 110C and 110B).

The distances between adjacent pairs of ring electrodes may be approximately equal. For example, the distance between the first pair of ring electrodes (e.g., ring electrodes 110C and 110D) and the second pair of ring electrodes (e.g., ring electrodes 110E and 110F) may be approximately equal to the distance between the second pair of ring electrodes and the third pair of ring electrodes (e.g., ring electrodes 110G and 110H). Thus, in some examples, the ring electrode pairs in electrode 110 may be considered to be equally spaced along the LA of catheter 102.

Although not shown, the system 100 may include one or more sensors for monitoring operating parameters (such as temperature, delivery voltage, etc.) through the medical system 100 and for measuring and monitoring one or more tissue characteristics (such as EGM waveform, monophasic action potential, tissue impedance, etc.), in addition to monitoring, recording, or otherwise conveying measurements or conditions of the surrounding environment within or at the distal portion of the energy delivery device or other components of the system 100. The sensor may be in communication with the controller 104 to initiate or trigger one or more alarms or ablative energy delivery modifications during operation of the energy delivery device.

Fig. 2A and 2B are conceptual diagrams illustrating example linear operations and focusing operations of a catheter according to one or more aspects of the present disclosure. Fig. 2C and 2D are conceptual diagrams illustrating example fields generated by linear operation and focusing operation of a catheter in accordance with one or more aspects of the present disclosure. The catheter 202 of fig. 2A and 2B may be an example of the catheter 102 of fig. 1.

Fig. 2A illustrates an example of how a controller, such as controller 104, may operate catheter 202 in a linear PFA mode. As shown in fig. 2A, to operate catheter 302 in a linear PFA mode, the controller may drive electrode 210A (e.g., a tip electrode) and electrode 210B (e.g., a tip ring electrode) with a first polarity (e.g., as a cathode in the example of fig. 2A). The controller may drive the electrodes 210C and 210D (e.g., first ring electrode pair) at a second polarity (e.g., as an anode in the example of fig. 2A) that is different from the first polarity. The controller may drive the electrodes 210E and 210F (e.g., the second ring electrode pair) with a first polarity and drive the electrodes 210G and 210H (e.g., the third ring electrode pair) with a second polarity. By driving the electrodes 210 (electrode pairs 210) with alternating polarities, the controller can achieve a field that is substantially linear along the axis of the catheter 202 as shown in fig. 2C. Generally, driving the electrode may include delivering energy to the electrode. For example, to drive the electrodes 210 with alternating polarities, the controller 104 may deliver energy to the electrode pairs 210 with alternating polarities.

In general, the electrodes of a ring electrode pair may be closer together than the electrodes of an adjacent electrode pair. For example, the distance between electrode 210C and electrode 210D may be less than the distance between electrode 210D and electrode 210E.

Fig. 2B illustrates an example of how a controller, such as controller 104, may operate catheter 202 in a focused PFA mode. As shown in fig. 2B, to operate catheter 302 in focused PFA mode, the controller may drive electrode 210A (e.g., a tip electrode) and electrode 210B (e.g., a tip ring electrode) with a first polarity (e.g., as a cathode in the example of fig. 2A). The controller may drive the electrodes 210C and 210D (e.g., first ring electrode pair) at a second polarity (e.g., as an anode in the example of fig. 2A) that is different from the first polarity. The controller may drive the electrodes 210E and 210F (e.g., second ring electrode pair) with the second polarity and drive the electrodes 210G and 210H (e.g., third ring electrode pair) with the second polarity. By driving the electrodes of electrode 210 near the tip in a first polarity and driving the other electrodes of electrode 210 in a second polarity, the controller can achieve a field that is substantially focused at the tip 202 of the catheter as shown in fig. 2D.

Fig. 3A and 3B are conceptual diagrams illustrating example linear operations and focusing operations of a catheter according to one or more aspects of the present disclosure. Fig. 3C and 3D are conceptual diagrams illustrating example fields generated by linear operation and focusing operation of a catheter in accordance with one or more aspects of the present disclosure. The catheter 302 of fig. 3A and 3B may be an example of the catheter 102 of fig. 1.

Fig. 3A illustrates an example of how a controller, such as controller 104, may operate catheter 302 in a linear PFA mode. As shown in fig. 3A, to operate catheter 302 in a linear PFA mode, the controller may drive electrode 310A (e.g., a tip electrode) and electrode 310B (e.g., a tip ring electrode) with a first polarity (e.g., as a cathode in the example of fig. 3A). The controller may drive the electrodes 310C and 310D (e.g., first ring electrode pair) at a second polarity (e.g., as an anode in the example of fig. 3A) that is different from the first polarity. In the linear mode, the controller may not drive the electrode 310E (e.g., the coil electrode). For example, the controller may float electrode 310E. By driving the electrode 310 in this manner, the controller can achieve a field that is substantially linear along the axis of the catheter 302 as shown in FIG. 3C. Thus, electrode 310 may include a tip electrode 310A, a tip ring electrode 310B (e.g., adjacent to tip electrode 310A), electrodes 310C and 310D (e.g., a ring electrode pair), and one or more additional electrodes (e.g., coil electrode 310E).

As described above, the electrode (e.g., electrode 310E) may be a coil electrode. The coil may take the form of a wound coil or, alternatively, as a spiral laser cut tube that is flexible like a coil but has a larger surface area. The number of windings can be adjusted to reduce or increase the surface area of the end or middle portions of the coil. In one example, the surface area at the distal end of the coil may be reduced (wider spaced coil windings). In this way, aspects of the invention may limit the electric field distribution around the end regions of the coil. In some examples, this may be an example of a short linear mode.

Fig. 3B illustrates an example of how a controller, such as controller 104, may operate catheter 302 in a focused PFA mode. As shown in fig. 3B, to operate catheter 302 in focused PFA mode, the controller may drive electrode 210A (e.g., a tip electrode) and electrode 210B (e.g., a tip ring electrode) with a first polarity (e.g., as a cathode in the example of fig. 2A). The controller may drive the electrodes 210C and 210D (e.g., first ring electrode pair) at a second polarity (e.g., as an anode in the example of fig. 2A) that is different from the first polarity. The controller may drive the electrode 210E (e.g., coil electrode) in a second polarity. By driving the electrodes of electrodes 310 in this manner, the controller can achieve a field that is substantially focused at the tip of catheter 302 as shown in fig. 3D.

Fig. 4 is a conceptual diagram illustrating an example focusing operation of a catheter in accordance with one or more aspects of the present disclosure. In particular, fig. 4 illustrates an example of how a controller (such as controller 104) may operate catheter 402 in a linear PFA mode. As shown in fig. 4, to operate catheter 402 in the linear PFA mode, the controller may drive electrode 410A (e.g., a tip electrode) and electrode 410B (e.g., a tip ring electrode) with a first polarity (e.g., as a cathode in the example of fig. 4). The controller may float the electrodes 310C and 310D (e.g., the first ring electrode pair) and drive the electrode 410E (e.g., the coil electrode) at a second polarity (e.g., as the anode in the example of fig. 4) that is different from the first polarity. By driving electrode 410 in this manner, the controller can create a more focused focus pattern in which ablation occurs closer to both tip electrodes 410A and 410B. In some examples, this may be an example of a long linear mode.

Fig. 5 is a block diagram illustrating an example controller of a multi-mode PFA system in accordance with one or more aspects of the present disclosure. The controller 504 of fig. 5 may be an example of the controller 104 of fig. 1. As shown in fig. 5, the controller 504 may include an energy generator 516, a processing circuit 518, a user interface 520, and a storage 522.

The energy generator 516 may be configured to provide electrical pulses to an electrode (e.g., electrode 110 of fig. 1) to perform an electroporation procedure on cardiac tissue or other tissue within a patient, such as kidney tissue, airway tissue, and organs or tissue within a cardiac space or pericardial space. For example, the energy generator 516 may be configured and programmed to deliver a pulsed high voltage electric field suitable for achieving desired pulses, high voltage ablations (referred to as "pulsed field ablations" or "pulsed electric field ablations"), and/or pulsed radio frequency ablations. Although shown as a single energy generator in the example of fig. 5, the energy generator 516 is not limited thereto. For example, the controller 504 may include a plurality of energy generators each capable of generating ablation signals in parallel.

The processing circuitry 518 may include one or more processors, such as one or more of the following: a microprocessor, controller, digital Signal Processor (DSP), application Specific Integrated Circuit (ASIC), field Programmable Gate Array (FPGA), discrete logic circuit, or any other processing circuit configured to provide the functionality attributed to processing circuit 518 that may be embodied herein as firmware, hardware, software, or any combination thereof. The processing circuit 518 controls the energy generator 516 to generate signals according to various settings (e.g., linear settings 530 or focus settings 532). In some examples, the processing circuit 518 may execute other instructions stored in the storage device 522 to perform PFA according to the linear setting 530 or the focus setting 532.

The storage 522 may be configured to store information within the controller 504 during operation, respectively. Storage 522 may include a computer-readable storage medium or a computer-readable storage. In some examples, storage 522 includes one or more of short term memory or long term memory. The storage 522 may include, for example, random Access Memory (RAM), dynamic Random Access Memory (DRAM), static Random Access Memory (SRAM), magnetic disk, optical disk, flash memory, or various forms of electrically programmable memory (EPROM) or electrically erasable programmable memory (EEPROM). In some examples, storage 522 is used to store data indicative of instructions that are executed, for example, by processing circuitry 518. As described above, the storage 522 is configured to store the linear settings 430 and the focus settings 532.

The user interface 520 may include buttons or a keypad, lights, speakers for voice commands, a display such as a Liquid Crystal (LCD), light Emitting Diode (LED), or Organic Light Emitting Diode (OLED). In some examples, the display includes a touch screen. The user interface 520 may be configured to display any information related to the execution of the PFA. The user interface 520 may also receive user input (e.g., selection of a linear PFA mode or a focused PFA mode) via the user interface 520. The user input may be in the form of, for example, pressing a button on a keypad or selecting an icon from a touch screen.

Fig. 6 is a flow diagram illustrating an example technique for performing both linear PFA and focused PFA using a single catheter in accordance with one or more aspects of the present disclosure. The technique of fig. 6 may be performed by a controller, such as the controller 104 of fig. 1 or the controller 504 of fig. 5.

The controller 504 may receive a PFA phantom selection (602). For example, the processing circuit 518 of the controller 504 may receive a selection from the practitioner via the user input device 520 whether to operate in a focus mode or a linear mode.

The controller 504 may determine whether to select the linear mode (604). In response to determining to use the linear PFA mode (e.g., the "yes" branch of 604), the controller 504 may drive the electrodes of the catheter to generate a linear field (606). For example, the processing circuitry 514 may cause the energy generator 516 to output energy to the electrodes of the catheter such that the electrodes generate a field having a geometry that is linear along the active portion of the particular catheter (e.g., similar to the fields illustrated in fig. 2C and 3C).

The controller 504 may determine whether a focus mode is selected (608). In response to determining to use the focused PFA mode (e.g., the "yes" branch of 608), the controller 504 may drive the electrodes of the catheter to generate a focusing field (610). For example, the processing circuitry 514 may cause the energy generator 516 to output energy to the electrodes of the catheter to cause the electrodes to generate a field having a geometry focused at the tip of a particular catheter (e.g., similar to the fields illustrated in fig. 2D and 3D).

The following numbered embodiments may illustrate one or more aspects of the present disclosure.

Embodiment 1. A method for performing Pulsed Field Ablation (PFA), the method comprising: determining, at a first time and by a controller connected to the particular catheter, to perform PFA using a linear PFA mode; responsive to determining to use the linear PFA mode, outputting, by the controller and to an electrode of the particular catheter, energy to cause the electrode to generate a field having a geometry that is linear along an active portion of the particular catheter; performing PFA using a focused PFA mode at a second time and determined by the controller; in response to determining to use the focused PFA mode, energy is output by the controller and to the electrode of the particular catheter to cause the electrode to generate a field having a geometry focused at the tip of the particular catheter.

Embodiment 2. The method of embodiment 1, wherein outputting energy to cause the electrode to generate a field having a geometry that is linear along the active portion of the particular catheter comprises: driving a tip electrode positioned at a distal tip of the catheter and a tip ring electrode adjacent to the tip electrode in a first polarity; driving the electrodes of the pair of ring electrodes with a second polarity opposite to the first polarity; and a coil electrode that does not drive the catheter, wherein the pair of ring electrodes is disposed longitudinally along the elongated structure between the tip ring electrode and the coil electrode.

Embodiment 3. The method of embodiment 1 or embodiment 2, wherein outputting energy to cause the electrode to generate a field having a geometry focused at the tip of the particular catheter comprises: driving a tip electrode positioned at a distal tip of the catheter and a tip ring electrode adjacent to the tip electrode in a first polarity; driving the electrodes of the pair of ring electrodes with a second polarity opposite to the first polarity; and driving a coil electrode of the catheter at the second polarity, wherein the pair of ring electrodes is disposed longitudinally along the elongated structure between the tip ring electrode and the coil electrode.

Embodiment 4. The method of embodiment 1, wherein outputting energy to cause the electrode to generate a field having a geometry that is linear along the active portion of the particular catheter comprises: driving a tip electrode positioned at a distal tip of the catheter and a tip ring electrode adjacent to the tip electrode in a first polarity; driving the electrodes of the first pair of ring electrodes with a second polarity opposite to the first polarity; driving electrodes of a second ring electrode pair with the first polarity, wherein the first ring electrode pair is longitudinally disposed between the second ring electrode pair and the tip ring electrode; and an electrode driving a third ring electrode pair with the second polarity, wherein the second ring electrode pair is disposed longitudinally between the first ring electrode pair and the third ring electrode pair.

Embodiment 5. The method of embodiment 1 or embodiment 4, wherein outputting energy to cause the electrode to generate a field having a geometry focused at the tip of the particular catheter comprises: driving a tip electrode positioned at a distal tip of the catheter and a tip ring electrode adjacent to the tip electrode in a first polarity; driving the electrodes of the first pair of ring electrodes with a second polarity opposite to the first polarity; driving electrodes of a second ring electrode pair with the second polarity, wherein the first ring electrode pair is longitudinally disposed between the second ring electrode pair and the tip ring electrode; and an electrode driving a third ring electrode pair with the second polarity, wherein the second ring electrode pair is disposed longitudinally between the first ring electrode pair and the third ring electrode pair.

Embodiment 6. The method of any of embodiments 2-5, wherein the first polarity is positive and the second polarity is negative.

Embodiment 7. The method of any of embodiments 2-5, wherein the first polarity is negative and the second polarity is positive.

Embodiment 8. A system, the system comprising: a conduit; and one or more processors configured to perform the method according to any one of embodiments 1 to 7.

Embodiment 9. A non-transitory computer-readable storage medium storing instructions that, when executed, cause a processing circuit to perform the method of any of embodiments 1-7.

The techniques described in this disclosure may be implemented, at least in part, in hardware, software, firmware, or any combination thereof. For example, aspects of the described technology may be implemented within processing circuitry, which may include one or more processors, including one or more microprocessors, digital Signal Processors (DSPs), application Specific Integrated Circuits (ASICs), field Programmable Gate Arrays (FPGAs); or any other equivalent integrated or discrete logic circuitry; and any combination of such components. The term "processor" or "processing circuit" may generally refer to any of the foregoing logic circuits, alone or in combination with other logic circuits, or any other equivalent circuit. The control unit including hardware may also form one or more processors or processing circuits configured to perform one or more techniques of this disclosure.

Such hardware, software, and firmware may be implemented and various operations may be performed within the same device, within separate devices, and/or within multiple devices, between or across multiple devices on a coordinated basis to support various operations and functions described in this disclosure. In addition, any of the described units, circuits, or components may be implemented together or separately as discrete but interoperable logic devices. Depiction of different features as circuits or units is intended to highlight different functional aspects and does not necessarily imply that such circuits or units must be realized by separate hardware or software components. Rather, functionality associated with one or more circuits or units may be performed by separate hardware components or software components, or integrated within common or separate hardware components or software components. The processing circuits described in this disclosure, including one or more processors, may be implemented as fixed function circuits, programmable circuits, or a combination thereof in various examples. A fixed function circuit refers to a circuit that provides a specific functionality using a preset operation. Programmable circuitry refers to circuitry that can be programmed to perform various tasks and provide flexible functionality in the operations that can be performed. For example, the programmable circuit may execute software or firmware that causes the programmable circuit to operate in a manner defined by instructions of the software or firmware. The fixed-function circuitry may execute software instructions (e.g., to receive stimulation parameters or output stimulation parameters), but the type of operation that the fixed-function circuitry performs is typically not variable. In some examples, one or more of these units may be different circuit blocks (fixed function or programmable), and in some examples, one or more of these units may be an integrated circuit.

The techniques described in this disclosure may also be embodied or encoded in a computer-readable medium (such as a computer-readable storage medium) containing instructions, which may be described as a non-transitory medium. Instructions embedded or encoded in a computer-readable storage medium may cause a programmable processor or other processor to perform the method, for example, when executing the instructions. The computer-readable storage medium may include Random Access Memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, a hard disk, a CD-ROM, a floppy disk, a magnetic tape cartridge, magnetic media, optical media, or other computer-readable media. It should also be understood that when an electrode is described as an anode or cathode, this does not mean that a direct current is delivered, but generally, the present disclosure uses such terms to refer to the opposite polarity of an electrode called an anode connected to an electrode called a cathode when an alternating current or most commonly a biphasic pulse waveform is delivered. Such biphasic waveforms may be delivered as a series of pulses (bursts) consisting of square pulses followed by negative square pulses, where such bursts may consist of tens or hundreds of such alternating polarity (biphasic) pulses.

Claims

1. A method for performing pulsed field ablation (PFA), the method comprising:

Performing PFA using a linear PFA mode is determined at a first time and by a controller coupled to a particular catheter;

In response to determining to use the linear PFA mode, outputting energy by the controller and to the electrodes of the particular catheter so that the electrodes generate a field having a geometry that is linear along an active portion of the particular catheter;

performing PFA using a focused PFA mode at a second time and determined by the controller; and

In response to determining to use the focused PFA mode, energy is output by the controller and to the electrode of the particular catheter to cause the electrode to generate a field having a geometry that is focused at the tip of the particular catheter.

2. The method of claim 1 , wherein outputting energy to cause the electrode to produce a field having the geometric shape that is linear along the active portion of the particular catheter comprises:

driving a tip electrode positioned at a distal tip of the catheter and a tip ring electrode adjacent to the tip electrode at a first polarity;

driving the electrodes of the annular electrode pair at a second polarity opposite to the first polarity; and

The coil electrode of the catheter is not driven, wherein the ring electrode pair is longitudinally disposed between the tip ring electrode and the coil electrode along the elongated structure of the particular catheter.

3. The method of claim 1 , wherein outputting energy to cause the electrode to produce a field having the geometry focused at the tip of the particular catheter comprises:

A coil electrode of the catheter is driven at the second polarity, wherein the ring electrode pair is disposed longitudinally along the elongated structure of the catheter between the tip ring electrode and the coil electrode.

4. The method of claim 1 , wherein outputting energy to cause the electrode to produce a field having the geometry that is linear along the active portion of the particular catheter comprises:

driving the electrodes of the first annular electrode pair at a second polarity opposite to the first polarity;

driving an electrode of a second annular electrode pair at the first polarity, wherein the first annular electrode pair is longitudinally disposed between the second annular electrode pair and the tip annular electrode; and

The electrodes of a third annular electrode pair are driven at the second polarity, wherein the second annular electrode pair is longitudinally disposed between the first annular electrode pair and the third annular electrode pair.

5. The method of claim 1 , wherein outputting energy to cause the electrode to produce a field having the geometry focused at the tip of the particular catheter comprises:

driving the electrodes of a second annular electrode pair at the second polarity, wherein the first annular electrode pair is longitudinally disposed between the second annular electrode pair and the tip annular electrode; and

6. The method of any one of claims 2 to 5, wherein the first polarity is positive and the second polarity is negative.

7. The method of any one of claims 2 to 5, wherein the first polarity is negative and the second polarity is positive.

8. A system, comprising:

Specific catheters; and

One or more processors of a controller, the one or more processors being configured to perform a method according to any one of claims 1 to 7.

9. A computer-readable storage medium storing instructions, which when executed cause a controller to perform the method according to any one of claims 1 to 7.