Systems and methods of pulsed field ablation

Abstract

To provide systems and methods for pulsed field ablation.SOLUTION: Provided are systems and methods to process motion signals obtained from at least one motion sensor during delivery of plurality of PFA pulses or pacing signals to heart tissue location(s) and determine degrees of diaphragm spasm affected by the PFA or pacing signals. In some embodiments the system identifies reduction of diaphragm spasm during delivery of PFA pulses to a certain location and upon such identification indicates that continued delivery of further PFA pulses to that certain location may cause irreversible damage to the Phrenic nerve. Additionally, or alternatively, the system utilizes the diaphragm spasm degrees measured following pacing or ablation of at least two heart tissue locations, to map the degrees of spasm affected by the ablation of various heart tissue locations and thereby enables ablation being conducted at location associated with reduced spasm.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to medical systems, particularly but not exclusively to cardiac ablation using irreversible electroporation (IRE) by pulsed field ablation. [Background technology]

[0002] Diagnosis and treatment of cardiac arrhythmias involves mapping the electrical properties of cardiac tissue, particularly the endocardium, and selectively ablating cardiac tissue through the application of energy, which can stop or modify the propagation of unwanted electrical signals from one part of the heart to another.

[0003] A typical ablation procedure involves inserting an ablation catheter having one or more electrodes at its distal end into a cardiac chamber so that at least one of the electrodes is in electrical contact with a site of abnormal electrical activity therein, and operating the electrode with an electrical signal that affects ablation of the site of abnormal electrical activity.

[0004] One ablation technique that has recently gained practical application is pulsed-field ablation (PFA), in which irreversible electroporation (IRE) is applied via a short electrical pulse, hereafter referred to as an electrical PFA pulse, which generates an electric field (typically greater than 450 volts / cm) high enough to irreversibly damage cells. In bipolar PFA ablation, the electric field is generated between two ablation electrodes at the distal end of the catheter, thus creating a local electric field / pulse in the target tissue. In monopolar PFA ablation, the electric field is generated between at least one ablation electrode at the distal end of the catheter and a return electrode, typically placed on the subject's skin and with a relatively large surface area to avoid affecting the ablation of nearby tissue.

[0005] PFA can be associated with certain adverse effects, particularly those associated with nerve stimulation, which can occur during delivery of PFA electrical pulses and / or pacing signals to certain tissue regions being treated. Such nerve stimulation, if it occurs, can be manifested by or lead to muscle contractions / spasms associated with the stimulated nerve, resulting in pain / discomfort for the treated subject and, in some cases, nerve damage. Accordingly, there are several known techniques aimed at mitigating / reducing nerve stimulation during PFA treatment or some of its adverse effects. [Brief explanation of the drawings]

[0006] In order to better understand the subject matter disclosed herein, and to illustrate how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which: [Figure 1] 1 is a schematic diagram of an ablation system 10 for pulsed field tissue ablation with an ablation control system adapted to monitor spasms or other adverse effects of nerve stimulation that may be caused by ablation, according to some embodiments of the present invention. [Figure 2] 1 is a block diagram illustrating the configuration of an ablation control system 100 according to an embodiment of the present invention. [Figure 3A] 3A and 3B are graphical representations of a spasm map 300 and guide instructions 303, respectively, which may be presented by the system 100 to guide a physician for ablation of tissue locations associated with spasm reduction. [Figure 3B] 3A and 3B are graphical representations of a spasm map 300 and guide instructions 303, respectively, which may be presented by the system 100 to guide a physician for ablation of tissue locations associated with spasm reduction. [Figure 4] 4 is a flowchart illustrating a method 400 for spatial mapping of spasms that may be implemented by the ablation control system 100, according to some embodiments of the present invention. [Figure 5] 6 is a flow chart illustrating a method 600 for monitoring the temporal evolution of seizures during PFA ablation, thereby identifying the risk of causing nerve damage due to continued ablation of a particular tissue location.

[0007] Like reference numbers are used in the figures to indicate like modules / elements of the invention or elements / modules with like functionality. Thus, unless otherwise stated, a description of a module / element with respect to a particular embodiment of the invention should be understood to apply to all embodiments of the invention incorporating such module / element. DETAILED DESCRIPTION OF THE INVENTION

[0008] In both bipolar and monopolar PFA ablation treatments, an electric field is generated / delivered through a subject's body between electrodes connected to an ablation energy generator, which can affect the stimulation of nerves present in the path of the ablation energy flow through the subject's body. Nerve stimulation can then cause involuntary contractions of a muscle or muscle group associated with the stimulated nerve during a PFA ablation treatment. Hereinafter, such involuntary muscle contractions resulting from nerve stimulation are referred to as spasms. Spasms may be accompanied by bursts of pain and discomfort for the subject and, in some cases, may provide an indication of the risk of permanent damage to the stimulated nerve. For example, when applying PFA ablation to a subject's heart, the phrenic nerve may be inadvertently stimulated, which may be manifested by spasms of the diaphragm and, in severe cases, may lead to phrenic nerve damage.

[0009] For this purpose, avoiding or reducing spasms during PFA treatment is desirable to reduce the subject's discomfort during treatment and also to avoid / reduce the risk of causing nerve damage.If muscle spasms caused by nerve stimulation cannot be completely avoided, it is still particularly important to avoid causing irreversible damage to the stimulated nerve.Specifically, it is important to avoid causing irreversible damage to the phrenic nerve, which controls the diaphragm and therefore the subject's breathing.

[0010] The techniques of the present invention are designed to achieve these goals and reduce or avoid spasms in PFA treatments (e.g., bipolar or monopolar treatments) and / or at least reduce the likelihood of causing irreversible damage to nerves affected by PFA ablation in the treatment area.

[0011] In one aspect of the present invention, the spasm levels affected by PFA ablation of several tissue locations within a target cardiac region of interest to be ablated are tested in a preliminary spasm testing procedure / phase that may occur before the actual ablation treatment and / or in real time during the ablation treatment. The spasm levels measured in response to ablation or pacing of several (two or more) test locations are used to generate a spatial spasm map that spatially relates tissue locations within the region of interest to the spasm levels expected by PFA ablation of those locations (the term pacing, as used herein, refers to the delivery of an electrical signal that does not affect ablation or that only causes reversible electroporation). The spatial spasm map can then be used to display / provide a physician with a spatial map showing the spasm levels expected by ablation of different locations within the tissue region of interest (e.g., to allow the physician to pre-plan a course / path for PFA ablation with reduced spasm prior to the actual PFA treatment). and / or generating guide indicia during PFA treatment to guide the physician to avoid ablation of tissue locations associated with excessive nerve stimulation or spasm. For example, during PFA ablation, the gradient / difference between the spasm magnitude affected by ablation of the location where the ablation electrode at the distal tip of the catheter is located and the spasm magnitude of other locations within the tissue region of interest may be calculated based on the spatial spasm map and further used to provide guidance to the physician as to the direction / location where the ablation electrode / catheter should be moved to avoid or reduce the affected spasm.

[0012] In another aspect, the present invention provides a technique for avoiding and / or reducing the risk of causing irreversible damage to a nerve (e.g., the phrenic nerve) during ablation therapy. This aspect of the present invention is based on real-time monitoring of certain symptoms during PFA therapy that indicate excessive nerve stimulation, which may cause irreversible damage. In particular, one such symptom is a reduction in the degree of spasm affected during PFA ablation of a specific tissue location. Indeed, if spasm is affected by PFA ablation of a specific tissue location, the spasm can be expected to persist (e.g., to a substantially similar extent) as long as PFA pulses continue to be delivered to substantially the same tissue location. However, if nerve damage begins to develop (even before it becomes irreversible) in the stimulated nerve that affects the spasm (which may be non-penetrating damage at this stage), the degree of spasm can be reduced (e.g., due to a reduced nerve response to the stimulation caused by the PFA pulse). Thus, the inventors of the present invention have realized that by monitoring the spasm level affected in real time during PFA ablation of a particular tissue location and looking for a reduction in the spasm level, it is possible to identify whether continued ablation of that tissue location is likely to cause nerve damage. Thus, according to this aspect of the present invention, the spasm level is monitored / measured during PFA ablation of each particular tissue location, and if a reduction / decrease in spasm level that is not associated with a change in the position of the ablation electrode is identified, instructions may be issued to inform the physician that further continued PFA ablation of that particular location may affect irreversible nerve damage, or the PFA treatment / pulses may be automatically stopped or modified (e.g., by reducing the intensity or repetition rate of the PFA pulses) to prevent nerve damage.

[0013] Referring initially to Figure 1, Figure 1 is a schematic diagram of a system 10 for ablating tissue in a subject 14 while avoiding / reducing spasms or other effects of neural stimulation, in accordance with some embodiments of the present invention. More specifically, system 10 is configured and operable to perform pulsed field ablation (PFA), also known as IRE ablation, in bipolar and / or monopolar modes.

[0014] System 10 includes an ablation catheter 12 having a distal tip 13 with one or more ablation electrodes 19 thereon adapted to contact and ablate a target tissue location intended for ablation. Catheter 12 is inserted into a subject 14 by a physician 16. For example, catheter 12 may be inserted into the subject's vasculature via an insertion point 30, and then its distal tip 13 may be navigated to a specific location within the subject's body (e.g., within the heart where the target tissue to be ablated is located).

[0015] Typically, catheter 12 includes a position sensor (not shown specifically) at its distal end 13 that provides data / signals indicative of the real-time position of catheter distal end 13 (the term position herein should be understood to refer to the position and / or orientation relative to the body of subject 14). Thus, the position of ablation electrode 19 within (relative to) the subject's body / target tissue can be tracked by system 10, thus enabling physician 16 to position ablation electrode 19 at a particular target tissue where ablation is desired and apply PFA to the location. It should be understood that in various embodiments, the system may include and / or be connectable to additional position sensors, which may be located, for example, on other medical devices, and may be adapted to track the positions of these sensors as well.

[0016] In some embodiments, the position sensor is a magnetic position sensor that operates in conjunction with a location pad 42 that includes multiple position signal transmitters (e.g., magnetic coils) that generate / transmit electromagnetic position signals (e.g., magnetic fields) within a predetermined working volume surrounding the patient. The real-time position of the distal tip 13 of the catheter 12 may then be tracked relative to the patient's body based on the magnetic / electromagnetic position signals generated using the location pad 42 and sensed by the magnetic-based position sensor. Details of magnetic-based position sensing techniques are described in U.S. Patent Nos. 5,391,199, 5,443,489, 5,558,091, 6,172,499, 6,239,724, 6,332,089, 6,484,118, 6,618,612, 6,690,963, 6,788,967, and 6,892,091, each of which is incorporated herein by reference.

[0017] According to embodiments of the present invention, system 10 is adapted to perform PFA ablation by delivering PFA pulses / signals through at least one ablation electrode 19 on distal end 13 of catheter 12. The system may be adapted to perform PFA ablation in a bipolar mode, in which the PFA pulses / signals are delivered between at least two ablation electrodes 19 of catheter 12, and in which the PFA pulses / signals are delivered between at least one ablation electrode 19 of catheter 12 and one or more return electrode patches, e.g., 28, which may optionally be coupled to subject 14 (e.g., placed on the skin or other body tissue of subject 14).

[0018] Generally, according to embodiments of the present invention, system 10 includes or is associated with one or more motion sensors 50 that may be positioned to sense movement of the patient's tissue / skin in a particular region of interest (ROI). For example, motion sensors 50 may be positioned near specific muscles (e.g., the diaphragm) associated with respective nerves (e.g., the phrenic nerve).

[0019] During or after delivery of the ablation therapy pacing signals or PFA pulses, the system 10 is adapted to monitor muscle movement based on signals obtained from the associated movement sensor 50, thereby determining whether muscle spasms, such as the diaphragm muscle, are affected due to stimulation of the respective nerve.

[0020] System 10 includes a console 18 containing one or more units that facilitate the execution of the techniques described herein. Typically, system 10 / console 18 includes one or more processors 20 having memory or storage on which appropriate operating software is stored and user interface capabilities on which the functionality of system 10 and / or its subsystems 100, 21, and 22, described below, is implemented. The ablation electrode 19 of catheter 12, and optionally, the return electrode patch 28 (if monopolar ablation therapy is performed), are typically connected to the system's console 18 via a cable 32 and an electrical interface (such as a port or socket). Sensor 50 is typically connected to console 18 wirelessly or by wire to provide data indicative of motion sensed thereby to console 18. In addition, a position sensor, typically located on the distal tip 13 of catheter 12, may also be connected to console 18 (e.g., by cable 32) to provide thereto position data / signals indicative of the real-time position of the catheter's distal end 13, and in particular its ablation electrode 19, based on magnetic-based position sensing as previously described herein.

[0021] Typically, the system 10, e.g., its console 18, further includes a user interface (UI) 34, which typically includes a display and a user input device (e.g., a joystick, mouse, keyboard, and / or other device) adapted to facilitate the performance of the ablation procedure by displaying relevant information to the physician 16 and receiving respective commands / inputs for performing the ablation procedure therefrom.

[0022] Console 18 may optionally provide multiple functions, including: (1) modeling endocardial anatomical structures in three dimensions (3D) and rendering a model or anatomical map for display via UI 34; (2) displaying activation sequences (or other data) compiled from recorded electrograms 21 in a representative visual display or image superimposed on the rendered anatomical map via UI 34; (3) displaying the real-time position and orientation of multiple catheters within the cardiac chambers; and (4) displaying areas of interest, such as where ablation energy is being applied. One commercially available product embodying elements of system 10 is available as the CARTO™ 3 system, commercially available from Biosense Webster, Inc., 31A Technology Drive, Irvine, CA 92618.

[0023] The console 18 also includes a PFA energy generator 22 configured to generate electrical PFA pulses, which are delivered to the target tissue to be ablated through the ablation electrode 19 of the catheter 12 during PFA ablation. Optionally, the PFA signal generator 22 is also adapted to generate a pacing current / signal that can be directed to pass through in a similar manner to the electrical PFA pulses but without affecting the ablation. In addition, the console 18 also typically includes / implements a position tracking system 21 that processes position data / signals obtained from position sensors that may be provided on medical devices, such as the catheter 12, connected to the system 10 and determines their respective positions relative to / within the patient's body. The position tracking system 21 is directly or indirectly connected to receive position-indicative signals from the position sensor at the distal tip 13 of the catheter 12 and, based thereon, can determine the position of the ablation electrode 19 relative to the target body / anatomical structure. In accordance with the present invention, system 10, e.g., console 18, includes an ablation control system 100 connected to ablation energy generator 22 and position tracking system 21 and adapted to monitor spasms occurring during PFA ablation treatment and / or delivery of pacing signals prior to actual ablation. Ablation control system 100 is adapted to process signals / data received from motion sensors 50, which may be provided on the patient's body over one or more muscles where spasms are to be monitored, to determine whether motion sensed in response to delivery of PFA / pacing signals via ablation electrodes 19 indicates muscle spasms caused by stimulation of a nerve. In various embodiments of the present invention, ablation control system 100 is adapted to monitor the occurrence of spasms relative to the location of the target tissue being ablated / paced (e.g., based on the position of distal end 13 of catheter 12 tracked by position tracking system 21).Based on the monitoring, ablation control system 100 assesses the evolution of spasm as a function of ablation duration (the time that PFA pulses or pacing signals are delivered to a particular target tissue / location) and / or as a function of the spatial location of activated ablation electrode 19. Based on the assessed spasm evolution, ablation control system 100 may issue instructions / guides to the physician indicating whether ablation of the target tissue at that location can be continued or preferably stopped (or the strength / amplitude of the ablation pulses should be reduced) to prevent / reduce nerve damage or spasm, and / or may optionally issue guide instructions indicating alternative positions / directions to which distal tip 13 of ablation catheter 12 can be moved to reduce spasm and thereby mitigate the effects of excessive nerve stimulation that may be caused by continued PFA ablation of the same tissue location. Alternatively or additionally, in some embodiments, the ablation control system 100 may automatically stop ablation treatments (e.g., delivery of PFA pulses) and / or modify their characteristics (e.g., intensity / repetition rate) to reduce the nerve stimulation affected thereby.

[0024] For example, ablation control system 100 may cause UI 34 to display the location / position of catheter 12, e.g., by overlaying an icon representing the catheter's distal tip 13 or its ablation electrode 19 onto an image of the target anatomy (the heart, in this particular example) at the particular location being ablated / paced, and may further present / provide an indication of the spasm and / or degree of spasm affected by the ablation / pacing of the tissue in which distal tip 13 is located. In embodiments, UI 34 may also present data indicating the particular muscles monitored by sensors 50 whose spasm is affected. Alternatively or additionally, in some embodiments, ablation control system 100 may cause UI 34 to present a spatial spasm map indicating the degree of spasm expected to be affected by ablation at different locations within a tissue region of interest (ROI) where ablation is sought. The spasm map may, for example, be overlaid on an anatomical image / map of the tissue ROI. The spasm map may be presented, for example, prior to an ablation treatment (e.g., after a preliminary spasm testing phase described below) to enable physician 16 to plan the ablation treatment accordingly. Alternatively or additionally, during an ablation treatment, in the event of spasm or spasm exceeding a certain level, ablation control system 100 may cause UI 34 to issue instructions regarding the direction of a nearby tissue location to which the distal tip of the catheter can be moved to reduce the affected spasm intensity. Instructions may be provided in the form of indicia displayed by the display of UI 34, such as an instruction arrow presented in relation to the target anatomical structure, or in other forms, such as audio instructions / guides. Alternatively or additionally, in some embodiments, ablation control system 100 monitors the evolution of spasm during the time PFA pulses are delivered to a particular region to identify features in the evolution of spasm time that may indicate a risk of causing damage / irreversible damage to one or more nerves, such as the phrenic nerve. The characterizing feature may be, for example, a decrease in spasm intensity sensed / measured during the administration of PFA pulses to the same tissue region.In response to such identification, the ablation control system 100 may cause the UI 34 to display a mark or otherwise provide a notification (e.g., by sound or other means) indicating that continued administration of PFA pulses to the same tissue location may result in nerve damage.

[0025] To this end, in some embodiments / implementations of the present invention, one or more of sensors 50 may be placed on / near each muscle (hereinafter referred to as a monitored muscle) whose spasm is to be monitored. Sensors 50 typically include motion sensors that may be placed on the patient's body (skin / tissue) near the monitored muscle, which may undergo spasm due to nerve stimulation by PFA treatment / pulses. Ablation control system 100 may be adapted to monitor signals obtained from sensors 50 following delivery of a pacing signal or PFA pulses via ablation electrodes 19 to identify / measure the occurrence of muscle spasms near sensors 50 in relation to the position of activated ablation electrodes 19 of catheter 12 that delivers the pacing signal or PFA pulses (e.g., the position of ablation electrodes 19 obtainable from position tracking system 21). The ablation control system 100 processes the measured degree of spasm as a function of space (position of the ablation electrode 19) and / or as a function of time over which the PFA pulses are delivered, thereby assessing the spatial distribution / map of spasm affecting locations within the tissue region of interest and / or the temporal evolution of spasm during PFA treatment, and based thereon issues guidance instructions or other instructions such as a spatial spasm map to guide the physician to locations of reduced spasm / neural stimulation or to provide instructions / warnings for continuing / stopping ablation at one or more specific locations.

[0026] Referring now to FIG. 2, FIG. 2 is a more detailed schematic block diagram of an ablation control system 100 for controlling pulsed field ablation PFA, according to some embodiments of the present invention. System 100 is adapted to monitor spasms during or before PFA ablation of a particular tissue region and assess / indicate the risk of affecting irreversible nerve damage, for example, to the phrenic nerve, based on identified spasm characteristics. This technology facilitates physician alert / instruction and / or automatic stopping (or automatic reduction of PFA pulse strength / amplitude and / or reduction of the rate / number of pulses of the PFA pulse train delivered for ablation of a particular tissue region) upon assessing that continued PFA ablation of a particular tissue region may cause irreversible nerve damage.

[0027] As shown, ablation control system 100 is connected or connectable to an ablation catheter 12 having at least one ablation electrode 19 at its distal end 13. In some embodiments, system 100 is capable / adapted to operate in a bipolar PFA mode and is connected or connectable to at least two ablation electrodes 19 for delivering PFA pulses therebetween. Alternatively or additionally, in some embodiments, ablation control system 100 is capable / adapted to operate in a monopolar PFA mode and may be connected or connectable to at least one (optional) return electrode patch 28 having a return electrode suitable for use in monopolar PFA ablation, thereby enabling delivery of PFA pulses between the ablation electrode 19 and the electrode patch 28 in monopolar PFA ablation.

[0028] 2, the system is connected or connectable to one or more motion sensors 50 that are or can be placed on the subject's body near the subject's muscles whose spasms are to be monitored during PFA treatment. For example, the motion sensors 50 may include a motion sensor placed near the patient's 14 diaphragm to sense spasms therein, and / or optionally two motion sensors placed / coupled near the left and right sides of the diaphragm, respectively, and optionally additional sensors 50 that monitor spasms in additional muscles.

[0029] Ablation control system 100 includes a seizure monitor 110, which may be implemented, for example, via processor 20 of system 10. The seizure monitor 110 is connected, directly or indirectly, by wireless or wired connection, to one or more movement sensors 50 placed on / coupled to the body of subject 14 near one or more muscles in which a seizure is to be monitored. The seizure monitor 110 is adapted to monitor / process the movement signals obtained from the movement sensors 50 to thereby identify whether the sensed movement manifests a seizure-related movement pattern indicative of a muscle spasm in one or more of the monitored muscles. Optionally, in some implementations, the seizure monitor 110 is also adapted to assess the degree / level / magnitude / intensity level of the sensed seizure, and optionally, the sensed seizure severity / level / magnitude based on the monitored movement signals.

[0030] Each motion sensor 50 may be implemented by or include a position sensor and / or an inertial measurement unit and / or an accelerometer and / or optionally a gyro. The motion sensors 50 may be adapted to provide, via a wireless or wired connection, signals indicative of changes in velocity or acceleration of muscle tissue coupled to the system 100, from which a seizure can be identified (e.g., based on inertial measurements performed by their IMU / accelerometer). In some embodiments, the motion sensors 50, or any one or more of them, may also include or be implemented by a position sensor trackable by the position tracking system 21. In some implementations, the motion sensors 50, or any one or more of them, may be aligned with the patient's body (e.g., based on the alignment of the location pad 42) so that indications identified thereby can be presented by the UI 34 over an anatomical map illustrating the muscle or associated nerve (e.g., ROI) being monitored by the respective sensor.

[0031] The seizure monitor 110 monitors the movement sensed by the movement sensors 50, for example, by processing / filtering the signals obtained from each respective movement sensor 50 (which may indicate changes in the position, velocity, and / or acceleration of the monitored muscle coupled thereto) to identify seizure-related movement patterns present in the movement signals. Thus, movement signals from movement sensors 50 positioned near the diaphragm (e.g., near the right and / or left side of the diaphragm) and / or near other muscles can be processed as described above to determine whether and / or to what extent a seizure is occurring in the monitored muscle. Such processing may also, in some cases, be performed periodically or over multiple time frames to assess the evolution of a seizure over time.

[0032] The seizure monitor 110 is also connected to the position tracking system 21 of the system 10. Upon detection of at least a seizure sensed by any of the sensors 50, the seizure monitor 110 utilizes the position tracking system 21 to monitor / determine the location within the patient where the delivered PFA pulse or pacing signal will cause a seizure (i.e., the location of the active ablation electrode 19 at the distal tip 13 of the catheter delivering the PFA pulse / pacing signal). The seizure monitor 110 utilizes information regarding whether and possibly the extent of a seizure occurring in any of the monitored muscles 50, along with the location data of the activated ablation electrode 19, and based on that information, determines / assesses the affected seizure or its extent as a function of the spatial location where the PFA pulse or pacing signal is delivered by the activated ablation electrode 19, and optionally monitors the evolution of the seizure in the monitored muscle as a function of time.

[0033] Based on this evaluation, PFA ablation control system 100 determines guides / instructions and / or spatial spasm maps to be provided to physician 16 to reduce over-stimulation / irritation of nerves (at least nerves associated with the muscles monitored by the motion sensors). Alternatively or additionally, in some embodiments, PFA ablation control system 100 may be adapted or configured to automatically interrupt the ablation operation (e.g., stop PFA pulses or automatically reduce their intensity / repetition rate) to avoid nerve damage, particularly irreversible nerve damage.

[0034] To this end, in various embodiments of the present invention, the PFA ablation control system 100 may include / implement any one or both of the following optional spasm handling modalities, and based on any one or both of these modalities, determine appropriate ablation instructions (guides / warnings) to be provided to the physician 16 and / or suspend normal operation of the ablation: Processing modality 122 - Spasm space mapping, and Processing Modality 124-Convulsive Temporal Progression.

[0035] I. Optional Processing Modalities 122 - Spatial Mapping Optionally, during / during or prior to ablation of a particular targeted tissue region of interest, modality 122 can be implemented to map the degree of spasm that is or will be affected by ablation at several locations in the target tissue region (i.e., map the degree of spasm as a function of the location of ablation electrode 19), thereby allowing for identification of preferred locations within the target tissue region where application of PFA ablation will result in reduced spasm and / or reduced other adverse effects of excessive neural stimulation.

[0036] To accomplish this, with the spasm space mapping modality 122 activated before or during the actual ablation, the physician 16 may navigate the distal end 13 of the catheter 12 to two or more locations within the target tissue region and deliver pacing signals or PFA pulses thereto via the ablation electrodes 19 of the catheter 12. The spasm monitor 110 then examines the muscle spasm response, monitored by the sensors 50, to the pacing signals or PFA ablation pulses delivered to the two or more locations. The spasm monitor 110 obtains from the position tracking system 21 the two or more locations to which the ablation electrodes 19 deliver pacing signals or PFA pulses, respectively, and determines the spasm intensity / amplitude affected by the delivery of the PFA pulse or pacing signal to these locations. The spasm monitor 110 records / stores each spasm intensity in association with each tissue location to which the PFA pulse or pacing signal is delivered, thereby mapping the spasm intensity as a function of the tissue location being paced / ablated.

[0037] As described above, the seizure space mapping modality 122 can be implemented in real time during a pre-spasm testing phase, which may be performed before the actual ablation, and / or during the ablation procedure itself. In the former case, during the pre-spasm testing phase, the physician 16 can test the seizure response to ablation of two or more tissue locations by delivering pacing signals to two or more tissue locations. After delivery of the pacing signals to two or more tissue locations, the seizure monitor 110 processes the signals sensed by the sensors 50 to identify whether a seizure-related motion pattern has been sensed therefrom and the respective degree / amplitude of the sensed seizure-related motion, thereby mapping the seizure response as a function of the location to which the ablation electrodes 19 deliver the pacing signals. In some implementations, the seizure space mapping may be further extended to tissue locations not specifically tested by the physician 16, for example, by interpolating or extrapolating the sensed spasm intensity from the two or more test locations to additional tissue locations.

[0038] Alternatively or additionally, the spasm space mapping modality 122 may be performed in real time during the ablation treatment. In this case, as each additional tissue location is ablated by the delivery of a PFA pulse, the spasm monitor 110 processes the motion signals sensed by the motion sensor 50 to identify whether a spasm-related motion pattern has been sensed thereby and their respective extents. Information regarding the degree of spasm affected by the ablation of different tissue locations may then be added / accumulated (e.g., in real time during the ablation treatment) to form or expand a spasm space mapping of spasm degree as a function of the ablated tissue location (e.g., optionally forming a spasm space mapping on the fly during treatment and / or expanding a spasm space mapping already formed, e.g., during a pre-test phase, by adding information regarding the degree of spasm affected by the ablation of additional locations). Also, in this example, the spasm space mapping may be measured for additional tissue locations and further extended, e.g., by interpolation or extrapolation, to tissue locations not specifically examined / ablated by the physician 16.

[0039] Optionally, based on the spasm space mapping 122, a spasm map indicating spasm intensity as a function of ablation location may be presented to the physician 16 (e.g., via the UI 34). The spasm map may be presented to the physician 16 during / after a pre-spasm testing phase and / or during the actual ablation to allow the physician 16 to set / decide on the course / path of tissue locations to be ablated, which ablation will result in a reduction in spasm (or other adverse neurostimulation effects). An example of such a map 300 that may be presented to the physician 16 is schematically illustrated in FIG. 3A, which is described in more detail below.

[0040] Alternatively or additionally, based on the spatial mapping of spasm intensity, system 100 can provide guidance to physician 16 regarding the spasm intensity expected from ablation of different tissue locations, enabling him or her to navigate the ablation electrodes of catheter 12 to positions where ablation is associated with reduced spasm. For example, in some implementations, during ablation of a particular tissue location, system 100 may operate UI 34 to present an image of the tissue region of interest (ROI) being ablated, along with indicia marking the location of the ablation electrodes, along with guide arrows or other indicia thereon to guide the physician in moving catheter 12 (ablation electrodes 19) in directions that reduce spasm and / or away from directions that increase spasm. Such indicia may be determined, for example, based on the gradient of spasm intensity in a spasm spatial mapping generated in real time during treatment or during a preliminary spasm testing phase. The guide indicia may be provided visually, for example, by guide arrows presented on UI 34 as described above, by audio prompts, or by other means. Alternatively or additionally, in some embodiments, during ablation treatment, physician 16 may also operate system 100 to display a map such as that shown in FIG. 3A showing the degree of spasm affected by ablation / pacing at different locations within the tissue region of interest.

[0041] FIG. 3A illustrates a spatial spasm map 300 that may be presented to the physician 16 based on operation of the spasm space mapping modality 122, according to an embodiment of the present invention. The boundaries of a particular tissue region of interest (ROI) where ablation is to be applied are marked in the figure. Locations 302 marked with small circles on the map 300 designate several examined tissue locations, the spasm response of each of which to ablation or pacing (e.g., reversible electroporation) was recorded / measured by the system 100. In this non-limiting example, the map 300 is presented on tissue surface coordinates TSC, whereby different spasm intensities / levels are indicated by different shading within the map 300. In this non-limiting example, three different shadings are used to classify the spasm intensity affected by ablation of different tissue locations into three levels: no spasm, low spasm, and high spasm. A map such as 300 presented in this figure can be used to present to the physician 16 the spasm degree affected in one of the muscles monitored under ablation / pacing of different tissue locations 302, or a calculated collective spasm degree calculated from the spasm degrees affected in multiple muscles monitored in response to ablation / pacing of different tissue locations. In this non-limiting example, the map 300 is extended by interpolation and / or extrapolation to additionally show the spasm degree expected to occur when ablating tissue locations other than the test points 302. That is, the spasm degree at the locations tested by the physician 16 is marked in the figure by a small circle on the map M, and the spasm degree between these test points 302 is assessed by interpolation and / or extrapolation of the spasm degree at the test points 302.

[0042] In the non-limiting example of FIG. 3B , guide indications 303 in the form of arrows are shown. The guide indications may be presented on the tissue region of interest (ROI) being ablated. In the particular non-limiting example shown in the figure, ablation around the ostium 304 of a pulmonary vein is desired. The guide indications 303 illustrate guidance that may be provided to the physician 16 in real time during an ablation treatment around the ostium 304, guiding the physician to ablate a location associated with lower spasm. In other examples, the ablation treatment may be an ablation line or area in another region of a heart chamber, e.g., the roof of the left atrium, or an area within the ventricle. For example, the guide indications 303 may be arrows indicating the gradient / difference in spasm severity affected between locations A and B, such that as the physician 16 ablates tissue location A, the system 100 guides the physician, e.g., in real time, to move toward ablation of location B, which will result in reduced spasm (as opposed to, e.g., proceeding to ablate tissue location C, which spans the desired region 304 but also results in ablation with a higher spasm severity).

[0043] Returning to FIG. 2 and, in particular, the optional spasm space mapping modality 122 in various embodiments, the spasm space mapping may be generated using as few as two (or preferably three or more) test locations 302 at which spasm intensities are tested / measured. The spatial mapping may optionally be recorded / stored in a data format, such as an association / lookup table, associating different test locations 302 within the tissue region to be ablated with the respective spasm intensities measured in response to ablation / pacing of those locations 302. Additionally or alternatively, the spasm space mapping may include, for example, predicted spasm intensities for other locations within the tissue region of interest ROI in addition to the one being tested. The predicted spasm intensities may be obtained by interpolation and / or extrapolation of the spasm intensities measured from the test locations 302.

[0044] Generally, a seizure space map as described above may be generated by the seizure monitor 110 for each motion sensor of the motion sensors 50 for each respective muscle of interest (i.e., for each muscle coupled to a respective motion sensor 50 of the sensors). Thus, in some embodiments, a separate seizure space map may generally be generated separately for each monitored muscle by the seizure monitor 110 based on processing of the motion signals respectively obtained from its corresponding motion sensor. For example, consider system 100 implemented with two motion sensors 50 coupled to the left and right sides of the diaphragm, respectively. The seizure monitor 110 may utilize / process the motion signals from these respective sensors 50 to separately determine spatial maps of the extent of seizures affected on the left and right sides of the diaphragm as a function of the position of the ablation electrodes 19. In this example, the seizure space map generated for each motion sensor 50 may include a first mapping indicative of seizures affected on the left side of the diaphragm as a function of the position of the ablation electrodes 19, and a second mapping indicative of seizures affected on the right side of the diaphragm as a function of the position of the ablation electrodes 19. The spatial mapping of different muscle spasms may generally differ, as different muscle spasms may be associated with stimulation of different nerves (in this example, for example, the left diaphragmatic side may be more sensitive to stimulation of the left phrenic nerve, and the right diaphragmatic side may be more sensitive to stimulation of the right phrenic nerve).

[0045] To this end, in certain embodiments / implementations, the spasm spatial mapping generated for each monitored muscle may be independently used by the system 100 to present the physician 16 with a spatial map such as 300 of affected spasms in each monitored muscle, and / or to provide the physician 16 with guides / marks 303 or warnings for avoiding / reducing spasms in each monitored muscle.

[0046] Alternatively or additionally, in some embodiments, the seizure monitor 110 is further adapted to combine data from multiple seizure space maps obtained for multiple monitored muscles, respectively, to form a collective seizure space map in which each tissue location 302 is associated with a particular collective seizure magnitude calculated as a function of the seizure magnitude affected in some / all of the monitored muscles according to the seizure space maps of the individual monitored muscles. Such a collective seizure space map may be generated, for example, by combining the seizure magnitudes sensed by multiple sensors 50 of multiple monitored muscles / nerves as a function of the positions of the ablation electrodes 19. The use of a collective spasm map may be advantageous in certain scenarios where multiple (two or more) muscles are monitored, as it can simplify the presentation of the spasm map 300 to the physician 16 (e.g., allowing the physician 16 to be presented with a single "collective" map 300 rather than one for each monitored muscle) and / or simplify the guidance and / or warnings given to the physician, while mitigating as much as possible conflicting guidance instructions that may result from separate spasm maps (e.g., according to a first spasm map of a first muscle, the catheter should be moved in a first direction to reduce spasm, and according to a second spasm map of a second muscle, the catheter should be moved in a different second direction to reduce spasm in the second muscle).

[0047] To this end, according to certain embodiments of the present invention, the seizure monitor 110 may be adapted to generate a collective seizure space mapping, in which the spasm intensities from all monitored muscles are incorporated to yield a single collective seizure intensity for each tissue location 302 of the ablation electrode 19 shown in the collective mapping.

[0048] One approach that may be implemented by system 100 for generating a collective spasm space mapping based on the spasm space mappings of individual muscles is to determine, for each tissue location, the collective spasm rate by aggregating (summing / integrating) the spasm rates indicated in the spasm space mappings of the individual muscles, thereby determining the collective spasm rate for such tissue location. In some implementations of the invention, the collective spasm rate for each tissue location may be formed by simply summing / integrating the spasm rates of the different muscles at that tissue location.

[0049] Alternatively or additionally, in some embodiments, the spasm monitor 110 may be adapted to calculate an aggregate spasm intensity for each tissue location by applying a differential sum / aggregation of the spasm intensities of the individual monitored muscles, such that for each tissue location, higher weights are given to muscles experiencing higher spasm intensities and lower weights are given to muscles experiencing lower spasm intensities at that location. In this regard, the following should be noted. (i) Different muscles may respond with different twitch amplitudes to the same level of stimulation applied to their associated nerves. (ii) During ablation, it is generally important to identify when a particular nerve is particularly strongly stimulated, resulting in strong spasms in its associated muscles, but it is less important when several nerves are weakly stimulated, resulting in weak spasms in each of those associated muscles (even if the sum of the amplitudes of several weak spasms appears strong).

[0050] Thus, in some embodiments of the present invention, system 100 may be configured and operable to generate an aggregate seizure map by difference summation / aggregation as shown above to give higher weight to muscles undergoing strong seizures and vice versa. To achieve that, spatial mapping modality 122 may be adapted to generate the aggregate seizure map by performing one or more of the following: (i) Regarding the first issue above, in embodiments / implementations in which motion sensors are coupled to different muscles having different amplitudes of seizure response to neural stimulation, normalization may be applied to the monitored spasm intensities obtained from the spasm monitor 110 for spasms in the different muscles. Normalization may be based not only on the spasm amplitude, but also on the purpose of setting the spasm intensities of the different muscles on a common scale reflecting the severity of the spasm to reflect the physiology of the different muscles and the respective levels of neural stimulation reflected by the spasm amplitude of the different muscles. Thus, in some implementations, reference data indicating the relationship between the spasm intensity / amplitude of each monitored muscle and the level of neural stimulation affecting the respective coincidence of each muscle spasm can be used as a physiological spasm normalization factor, thereby normalizing the spasm intensities of the different monitored muscles to place them on a common scale before generating an aggregate spasm map. (ii) With regard to the second issue discussed above, the spasm intensities (e.g., normalized as shown in (i) above) for each test point 302 may be aggregated to give higher weight to spasms of particular muscles associated with strong nerve stimulation and lower weight to spasms of weaker muscles associated with weakly stimulated nerves. For example, in certain implementations, the system may apply a particular squashing function (e.g., a sigmoid function, or any other suitable squashing function as understood by those skilled in the art) to the spasm intensities obtained from the spasm monitor for each monitored muscle (e.g., after normalization) to give higher weight to muscles experiencing higher spasm intensities / amplitudes in the exchangeable map, and then sum the (e.g., normalized) squashed spasm intensities of multiple monitored muscles for each test location 302 of the ablation electrode 19 to produce an exchangeable spasm intensity map of multiple monitored muscles for each test location 302 reflecting spasm severity with higher weights for strongly stimulated muscles. Alternatively, in some implementations, a collective spasm intensity map may be obtained by considering (e.g., summing) only muscles that experience high / maximum spasm intensity (e.g., normalized), and not considering (e.g., not including in the summation) muscles whose spasm intensity (e.g., normalized) is below a certain threshold. This may be done for each test location of the ablation electrode 19, resulting in an exchangeable spasm map.

[0051] Thus, as described above, system 100 can utilize spasm space mapping (e.g., collective spasm space mapping or muscle-specific spasm space mapping) to present physician 16 with a map such as 300 shown in FIG. 3A indicating the degree of spasm expected to be affected by ablation of different tissue locations. Typically, such spasm map 300 may be presented to physician 16 prior to the actual ablation treatment (e.g., after a preliminary spasm testing phase in which spasm space mapping may be constructed) to enable physician 16 to plan the course / path of ablation along the tissue region of interest with reduced spasm effects. Alternatively or additionally, spasm map 300 may also be presented to physician 16 at a later stage (e.g., per physician direction), e.g., in real time during the ablation treatment itself. Further alternatively or additionally, spasm space mapping may be used by system 100, typically during the ablation treatment, to issue warnings and / or guidance instructions to physician 16 to perform PFA treatment while avoiding or reducing unwanted / excessive nerve activity. To accomplish this, the seizure space mapping modality 122 utilizes seizure space mapping during ablation treatment to provide instructions / guides to the physician 16 (e.g., via a graphical display 303, as in FIG. 3B , or by auditory or other cues, for example) to navigate the ablation catheter to a relatively “safe” position within the region of interest ROI, where ablation is expected to result in reduced seizures. For example, in some implementations based on the collective seizure space mapping and the current position of the ablation electrode 19, an auditory warning / guide may be generated to guide the physician 16 to move the ablation electrode from its current position (e.g., in a particular direction) to avoid or reduce neural stimulation.

[0052] Optionally, in embodiments / implementations in which the spasm space map 300, such as that of FIG. 3A, or the guide markings 303, such as those of FIG. 3B, are displayed graphically, they may be displayed as an overlay on a model / image of the target anatomical structure that at least partially includes the ROI to be ablated. In such embodiments, the system 100 may be capable of acquiring anatomical structure data (model or image) of the target endocardial anatomical structure (e.g., the target heart or a portion thereof) within the ROI to be treated by PFA. As described above, the endocardial anatomical structure may be modeled by the system 10 based on imaging and / or based on tracking the three-dimensional positioning of a catheter inserted into a heart chamber.

[0053] The anatomical data (model or image) is typically aligned with the subject's body based on, for example, a position reference of the subject's body provided by position tracking system 21, and thus spasm space map 300 or guide markings 303 (e.g., as illustrated in FIGS. 3A and / or 3B, respectively) are presented to physician 16 as an overlay on the anatomical model or image with appropriate spatial alignment in some embodiments. Optionally, system 100 may further be adapted to align the position of catheter distal tip 13 (e.g., or the position of its active ablation electrode 19 on the anatomical model / image), optionally with markings (e.g., as obtained from map 300) indicative of the degree of spasm affected at that position of distal tip 13 and / or at surrounding positions, and / or markings 303 indicative of the expected gradient / difference in the degree of spasm that will be affected if catheter distal tip 13 is moved to one of the surrounding positions.

[0054] 4, there is shown in a self-explanatory manner a flow diagram of a method 400 of the seizure space mapping modality 122 according to an embodiment of the present invention. The method 400 may optionally be implemented by the system 100 (e.g., via its processor 20) according to some embodiments of the present invention.

[0055] In operations 410 and 420, an ablation catheter 12 having at least one ablation electrode 19 for PFA ablation is provided, as well as one or more motion sensors 50 positioned in various areas near muscles (such as the diaphragm) whose spasms are to be monitored during the PFA procedure.

[0056] In operation 430, spasm spatial mapping can be determined by performing operations 432 through 438. In operation 432, system 100 enables physician 16 to move the catheter to deliver PFA pulses and / or pacing signals to the target tissue while moving the ablation electrode to two or more spatial locations in the target tissue. Operations 434 and 436 are performed by system 100 during delivery of the PFA pulses and / or pacing signals to monitor the signals of each motion sensor to thereby determine the spasm degree / level affecting the muscle associated with that motion sensor (operation 434), while also monitoring two or more spatial locations 302 of ablation electrode 19 (operation 436), in conjunction with which the spasm degree / level is determined in operation 434 (i.e., monitoring the position of ablation electrode 19 based on signals from the catheter's position sensor tracked by position tracking system 21).

[0057] Operation 430 may be performed to determine a specific mapping of spasm for each individual muscle being monitored by one of sensors 50. Operation 430 may be performed by physician 16 prior to actual ablation by delivery of pacing signals to two or more test locations 302 in the tissue region of interest to be ablated and / or in a pre-spasm test phase, which may be performed in real time during an ablation treatment in which PFA pulses are delivered to two or more test locations 302. Operation 430 therefore includes the following sub-operations: A sub-operation 432 in which pacing signals are delivered in a pre-convulsion test phase or PFA pulses are delivered in real time via ablation electrodes 19 located at two or more test locations 302 within the tissue region of interest. Sub-operation 434 is performed in parallel with sub-operation 432 and includes monitoring, in association with each test location 302, the degree of spasm affecting the monitored muscle by processing signals from its respective movement sensor 50 (e.g., to identify the amplitude of the spasm-related movement pattern exhibited thereby). In sub-operation 436, a muscle-specific spasm space mapping is determined for the monitored muscle by recording / storing the association between each spasm intensity affecting the muscle and each test location 302 of the ablation electrode 19, as determined in sub-operation 434 for two or more test locations 302. In optional sub-operation 438, the spasm space mapping for a particular muscle may be further extended by interpolation / extrapolation of the spasm intensity measured in 434 to assess the spasm intensity affected by ablation of additional tissue locations in addition to those examined in 432 and 434.

[0058] It should be appreciated that operation 430 may be performed in parallel (or sequentially / at different times) for multiple muscles whose twitches are being monitored by sensor 50, thereby determining muscle-specific twitch space mappings for each of the multiple muscles (e.g., if multiple muscles are being monitored).

[0059] Optionally, in some embodiments in which multiple muscles are monitored, operation 440 may be performed by seizure monitor 110 to determine, for each location of ablation electrode 19, an aggregate seizure space mapping representing an aggregate seizure intensity calculated from the seizure intensities affecting the multiple monitored muscles. This may be performed by combining the seizure intensities of the multiple muscle-specific seizure space mappings using any one of the techniques described above (e.g., in various embodiments, normalization is applied to set the seizure intensities of different muscles on a common scale, and / or in various embodiments, differential weighting is applied to assign higher weights to muscles experiencing higher seizure intensities for each tested location).

[0060] In operation 450, seizure information may be presented to physician 16 based on any one of the muscle-specific seizure space mappings obtained in 430 and / or optionally based on the collective seizure space mapping obtained in 440. Operation 450 typically includes at least one of the following: Optional sub-operation 452 in which a spasm space map, such as 300 in FIG. 3A , may be displayed to the physician 16 via the UI 34. The displayed map 300 may be based on any of the muscle-specific spasm space mappings obtained in 430, or preferably, in some embodiments, on the collective spasm space mappings obtained in 440 for multiple monitored muscles. In some embodiments, the spasm space map 300 may be displayed to the physician 16 prior to the actual ablation treatment (e.g., after an optional pre-spasm testing phase) to allow the physician 16 to plan a path / route of tissue ablation within the region of interest that will result in spasm reduction. Alternatively or additionally, the spasm space map 300 may be displayed to the physician 16 at any other stage (e.g., in real time during the ablation treatment and / or at any other time upon the physician's request), and / or In optional sub-operation 454, catheter navigation guides (e.g., alerts and / or instructions 303 as shown in FIG. 3B ) may be provided to physician 16 in real time during the actual ablation treatment to guide the physician to navigate catheter 12 to a location with reduced spasm. Sub-operation 454 may include tracking the position of ablation electrode 19 during delivery of PFA pulses in the ablation treatment and determining and providing to physician 16 guide instructions / indications for navigating ablation electrode 19 of catheter 12 to a location associated with reduced spasm based on spasm space mapping (e.g., muscle-specific mapping acquired in 430 or collective mapping acquired in 440). For example, in this operation, system 100 may utilize spasm space mapping to identify / determine one or more tissue locations near the tracked location of ablation electrode 19, the ablation of which is expected to result in reduced spasm, and providing guides / instructions to physician 16 to navigate ablation electrode 19 toward these one or more tissue locations.

[0061] II. Optional Processing Modalities 124-Convulsive Temporal Progression 2 , during ablation of each tissue location within the tissue region of interest ROI, processing modality 124 can optionally be executed by system 100 to monitor the temporal evolution / progression of spasm during the actual ablation of that tissue location, thereby assessing / identifying when nerve damage may begin to develop with continued delivery of PFA pulses to that tissue location. To accomplish this, spasm monitor 110 tracks the position of active ablation electrode 19 and monitors changes in the degree of spasm exhibited by each particular muscle monitored by sensor 50 during the delivery of a series of PFA pulses to that target tissue location, to identify whether changes in the degree of spasm during the PFA pulse train indicate the likelihood of possible development of nerve damage with continued delivery of PFA pulse trains to that location.

[0062] To accomplish this, the spasm monitor 110 utilizes information from the position tracking system 21 to track the position of the active ablation electrode 19 during delivery of the PFA pulse train. In parallel, the spasm monitor 110 processes the sensed movement signals from each specific muscle of the subject to which the sensor 50 is coupled and, based on this processing, determines the evolution of the degree of spasm experienced by the specific muscle over time during delivery of the PFA pulse train. The spasm monitor 110 is adapted to identify cases in which the change / evolution of the degree of spasm is characterized by a decrease in the degree of spasm in at least one monitored muscle (e.g., the diaphragm), which cannot be attributed to a change in the position of the ablation electrode 19. For example, the spasm monitor 110 can be adapted to identify a decrease in muscle spasm that occurs during a time period in which the ablation electrode 19 is active to deliver PFA pulses to substantially the same tissue location and associate such a decrease in the degree of spasm with the possible development of nerve damage in the nerve associated with the muscle. To this end, upon identifying that the decrease / reduction in spasm intensity is substantial, e.g., above a certain threshold, and cannot be attributed to a change in the position of the ablation electrode 19, the spasm monitor 110 determines / warns that continuing to deliver PFA pulse trains to the same tissue location (e.g., without reducing the intensity of the PFA pulses) may cause further damage to the nerve associated with the muscle representing the decrease in spasm; for example, a reduction in diaphragm spasm during ablation of the same location may indicate the early development of damage to the phrenic nerve.

[0063] For example, in some embodiments in which the seizure monitor 110 implements the temporal evolution processing modality 124, it may be adapted to stop / modify ablation and / or warn of the risk of causing nerve damage if the following conditions are identified during delivery of a PFA pulse train to substantially the same tissue location: The spasms expressed in the particular muscle being monitored develop to a particular spasm intensity, and then the spasm intensity declines / reduces while the delivery of the PFA pulse train continues to substantially the same tissue location (e.g., an identified decline / reduction in muscle spasm intensity that is not due to a change in the position of the ablation electrode 19 or a change / reduction in the intensity of the PFA pulses).

[0064] In this case, the reduction / decrease in muscle spasm intensity is likely due to nerve damage beginning to develop in the nerve associated with the monitored muscle (e.g., the development of nerve damage may cause the nerve being stimulated by the PFA pulse to stop responding appropriately to the stimulation, thereby resulting in a reduction in muscle spasm).

[0065] Thus, in embodiments in which system 100 implements seizure temporal evolution processing modality 124, seizure monitor 110 may be adapted to process the degree of spasticity in at least one muscle (e.g., the diaphragm) monitored by each sensor 50 to identify when the seizure evolution over time exhibits the conditions indicated above. If the seizure evolution in the monitored muscle exhibits this condition (e.g., a decrease in spasticity without an apparent reason, such as a change in ablation electrode position or PFA pulse intensity), seizure monitor 110 may determine that nerve damage may be beginning to develop in its associated nerve (e.g., the phrenic nerve if the monitored muscle is the diaphragm). Optionally, seizure monitor 110 may also operate to identify other conditions that may be associated with the possible development of nerve damage represented by the seizure temporal evolution, such as when the spasm of a particular muscle develops / increases beyond a certain threshold during delivery of PFA pulses. In the case of an identified condition indicating a risk of causing nerve damage, the seizure monitor 110 can optionally operate the UI 34 to issue a respective instruction / warning to the physician 16 about the risk of causing nerve damage from further delivery of PFA pulses to the location of the ablation electrode 19 (while potentially also indicating the muscle exhibiting the identified condition). Alternatively or additionally, if such a condition is identified as exhibiting, the seizure monitor 110 can optionally operate (e.g., operate the ablation energy generator 22) to stop further delivery of PFA pulses or reduce the intensity, repetition rate, or other characteristics of the PFA pulse train delivery to prevent nerve damage.

[0066] As mentioned above, in some embodiments, system 100 may be connected to / include two or more sensors 50 (e.g., two or more motion sensors 50) placed at different locations on the body of patient 14 to monitor seizures in different muscles or muscle sections. To this end, it should be understood that in embodiments / implementations in which several sensors 50 are connected to system 100, seizure temporal evolution processing modality 124 may be run independently / separately for each muscle / muscle section monitored by each sensor 50 to separately assess whether the temporal evolution of a seizure in each muscle indicates a risk of damage to its associated respective nerve.

[0067] 5, there is shown in a self-explanatory manner a flow diagram of a method 600 of the seizure temporal evolution processing modality 124 according to an embodiment of the present invention. The method 600 may optionally be implemented by the system 100 (e.g., via its processor 20) according to some embodiments of the present invention.

[0068] In operations 610 and 620, an ablation catheter 12 having at least one ablation electrode 19 for PFA ablation is provided, as well as one or more motion sensors 50 positioned near one or more muscles, such as near the left and right sides of the diaphragm, whose temporal evolution of spasms is monitored during PFA treatment.

[0069] In operation 630, system 100 facilitates movement of catheter 12 by physician 16 to deliver a PFA pulse train to a tissue location within the region of interest of subject 14 to ablate tissue thereat. Operation 640 is performed during delivery of the PFA pulse train in operation 630 to provide a warning to physician 16 or stop / modify delivery of the PFA pulse train if excessive neural stimulation affected by the delivery is identified based on the temporal evolution of the spasm. Operation 640 typically includes the following, which may be performed separately for each of one or more of the muscles monitored by a corresponding one of sensors 50: Act 642: Monitor the degree of spasm of the monitored muscle during the duration of the PFA pulse train delivery based on the signals (eg, movement signals) obtained from its respective sensor. ACT 644: Monitor the position of the ablation electrode 19 for the duration of the PFA pulse train delivery based on position signals obtained from the catheter's position sensor (eg, if processed by the position tracking system 21). Operation 646 is then executed to determine / assess the temporal evolution / development of a spasm in each monitored muscle during delivery of a PFA pulse train to a particular target tissue location. Optionally, operation 646 includes assessing portions / portions of the evolution of spasm intensity for each monitored muscle acquired in 642 that are not related to changes in the position of the ablation electrode 19. To this end, operation 646 may utilize / consider the position of the ablation electrode 19 during the time of PFA pulse delivery to assess spasm evolution / changes that are not attributable to changes in the position of the ablation electrode 19. For example, in some embodiments, operation 646 considers only portions / portions of the spasm temporal evolution during which the ablation electrode remained substantially static / stationary at the same tissue location, thereby ignoring / excluding features of the spasm evolution that may be attributable to changes in the position of the ablation electrode 19. Alternatively or additionally, in some embodiments, particularly those in which a seizure space mapping modality 122 is implemented by system 100, the portion of the seizure temporal evolution that is not attributable to changes in the position of the ablation electrode 19 can be assessed by normalizing (e.g., dividing) the monitored muscle spasm intensity during the duration of the PFA pulse obtained in operation 642 based on / by the expected spasm intensity at the different tissue locations 302 at which the ablation electrode 19 is located during the time the seizure temporal evolution is monitored. To accomplish this, the expected spasm intensity at the different tissue locations 302 can be obtained based on, for example, that determined in operation 430 of the seizure space mapping modality 122 in method 400 described above. In a specific, non-limiting example, such normalization can be performed by simply dividing the sensed spasm intensity in operation 642 during each time slot of the PFA pulse train delivery by the respective expected spasm intensity obtained from the spasm space-dependence map of the seizure space mapping modality 122 for the particular location of the ablation electrode in each time slot. Thus, a normalized evolution of the spasm in the monitored muscle during / as a function of time of PFA pulse train delivery, which is not due to changes in the position of the ablation electrode, can be obtained in act 646.As will be understood by those skilled in the art after becoming aware of the present invention, other techniques may be used instead of the normalization described above to account for / compensate for changes in the position of the ablation electrode 19 in the temporal evolution of a seizure.

[0070] Then, in operation 648, the seizure time evolution / development, i.e., at least the portion / portions thereof not related to changes in the ablation electrode position, can be processed by the seizure monitor 110 to identify features indicative of excessive stimulation of the nerve associated with the monitored muscle whose seizure time evolution is being evaluated (e.g., the phrenic nerve in the case of the diaphragm). One such characterizing feature typically identified in operation 648 is the condition shown above, where, during PFA ablation, the degree of spasticity in a particular muscle reaches a particular level and then begins to decrease (the decrease is not due to cessation / reduction of the PFA pulse train or a change in the delivery location of the PFA pulses). Identification of a decrease in the degree of spasticity during ablation of a particular location can indicate that the nerve associated with the particular muscle may be undergoing initiation of damage. Another characteristic of possible nerve injury that may optionally be evaluated in operation 648 is when the spasm intensity of a particular muscle increases above a particular level (maximum spasm intensity threshold), and the increase is not due to a change in the characteristics of the PFA pulses within the pulse train (e.g., their intensity / repetition rate) or a change in the delivery of the tissue location pulses. Thus, upon recognizing these characteristics, a determination may be made by the seizure monitor that the nerve associated with the particular muscle to which modality 124 is applied may be overstimulated by the PFA pulses and may be damaged if such overstimulation persists. Thus, in these cases, in operation 650, the seizure monitor 110 may optionally operate the UI 34 to issue a warning / instruction to the physician 16 indicating the affected overstimulation (which may indicate the nerve / muscle being overstimulated). Alternatively, or in addition, during operation 650, the seizure monitor 110 may optionally operate to automatically stop the PFA pulses or modify their characteristics (e.g., reduce their intensity / frequency), thereby reducing nerve stimulation and preventing nerve damage.

[0071] As described above, method 600 can be performed independently / separately for each muscle / muscle section being monitored by one of sensors 50 of system 100 to independently assess whether the nerve associated with the respective muscle is being overstimulated, and in the latter case alert the physician or stop / modify the PFA treatment / pulse. [Example]

[0072] Example 1. A method for pulsed field ablation (PFA), comprising: providing a PFA system including an ablation catheter and a pulsed field ablation energy generator connectable to one or more ablation electrodes disposed on a distal tip of the catheter and facilitating tissue ablation near the distal tip via delivery of PFA pulses to at least one of the ablation electrodes; providing at least one motion sensor positioned at at least one respective location on the patient's tissue / skin near the patient's diaphragm; The method includes processing motion signals obtained from at least one motion sensor during a PFA treatment in which multiple successive PFA pulses are delivered to specific locations of cardiac tissue by one or more electrodes to determine a degree of diaphragm spasm caused by the multiple successive PFA pulses delivered to the specific locations, identifying a reduction in diaphragm spasm affected by the delivery of the successive PFA pulses to the specific locations, and determining that continued delivery of additional PFA pulses to the specific locations may cause irreversible damage to the phrenic nerve if the reduction in diaphragm spasm is identified to exceed a certain threshold.

[0073] Example 2. The method of Example 1, wherein the at least one motion sensor includes at least two motion sensors positioned near the left and right sides of the patient's diaphragm to sense diaphragmatic spasms resulting from stimulation of the left or right phrenic nerve by a PFA pulse or pacing signal.

[0074] Example 3. The method of Example 1 or 2 adapted for use in bipolar PFA therapy.

[0075] Example 4. The method of any one of Examples 1 to 3, adapted for use in monopolar PFA treatment.

[0076] Example 5. At least one motion sensor comprises: one or more position sensors, wherein the method includes processing position signals from the one or more position sensors and deriving a movement signal based on a change in position of each of the position sensors; - one or more inertial measurement units (IMUs), adapted to provide motion signals based on inertial measurements performed thereby; - one or more accelerometers adapted to provide a movement signal.

[0077] Example 6. The method of any one of Examples 1 to 5, wherein at least one motion sensor is a wireless sensor including a wireless communication utility capable of wirelessly communicating motion signals to the PFA system.

[0078] Example 7. A method for pulsed field ablation (PFA), comprising: providing a PFA system including an ablation catheter, a pulsed field ablation energy generator connectable to one or more ablation electrodes disposed at a distal tip of the catheter and facilitating tissue ablation near the distal tip via delivery of PFA pulses to at least one of the ablation electrodes, and a position tracking system connectable to a position sensor disposed near the distal tip of the catheter and adapted to track the position of the one or more ablation electrodes at the distal tip; providing at least one motion sensor positioned near the patient's diaphragm; and processing motion signals obtained from at least one motion sensor during delivery of a plurality of PFA pulses or pacing signals by a catheter to at least two respective locations within the patient's cardiac tissue to determine spasm degrees associated with the delivery of the PFA pulses or pacing signals to the at least two cardiac tissue locations, respectively, and correlating the spasm degrees to the at least two cardiac tissue locations, thereby mapping diaphragm spasm degrees affected by the delivery of the PFA pulses or pacing signals to the two or more cardiac tissue locations.

[0079] Example 8. The method of Example 7, including utilizing mapping in real time during PFA treatment in which PFA pulses are delivered to a specific location of cardiac tissue, and determining, according to the mapping, at least one other tissue location near the specific location that is associated with reduced spasm relative to the spasm affected by ablation of the specific location, and issuing guide instructions for ablation of the other tissue location.

[0080] Example 9. The method of Example 7 or 8, comprising utilizing mapping to display a map indicating the degree of spasm expected to be affected by ablation of various tissue locations within the region of interest of cardiac tissue to be ablated.

[0081] Example 10. Mapping During a seizure testing phase performed prior to PFA ablation therapy, multiple pacing signals are delivered to at least two respective locations of cardiac tissue; and - in real time during PFA treatment, wherein multiple PFA pulses are delivered to at least two respective locations of the cardiac tissue.

[0082] Example 11. The method of any one of Examples 1 to 10, wherein the at least one motion sensor includes at least two motion sensors positioned near the left and right sides of the patient's diaphragm to sense diaphragmatic spasms resulting from stimulation of the left or right phrenic nerve by a PFA pulse or pacing signal.

[0083] Example 12. The method of any one of Examples 1 to 11, adapted for use in bipolar PFA therapy.

[0084] Example 13. The method of any one of Examples 1 to 12, adapted for use in monopolar PFA treatment.

[0085] Example 14 . At least one motion sensor comprises: one or more position sensors, wherein the method includes processing position signals from the one or more position sensors and deriving a movement signal based on a change in position of each of the position sensors; - one or more inertial measurement units (IMUs), adapted to provide motion signals based on inertial measurements performed thereby; - one or more accelerometers adapted to provide a movement signal.

[0086] Example 15. The method of any one of Examples 1 to 14, wherein at least one motion sensor is a wireless sensor including a wireless communication utility capable of wirelessly communicating motion signals to the PFA system.

[0087] Example 16. A system for pulsed field ablation (PFA), comprising: an ablation catheter having one or more ablation electrodes at a distal end thereof; a position sensor disposed on the ablation catheter that provides data indicative of the position of the distal end of the ablation catheter; at least one motion sensor for coupling to or near at least one region of the subject's body near the diaphragm; a PFA energy generator connectable to one or more ablation electrodes disposed on the distal end of the ablation catheter and facilitating tissue ablation near the distal end via delivery of PFA pulses to at least one of the ablation electrodes; The system, (a) processing motion signals obtained from at least one motion sensor during a PFA treatment in which multiple successive PFA pulses are delivered by one or more electrodes to specific locations in cardiac tissue to determine a degree of diaphragm spasm caused by the multiple successive PFA pulses delivered to the specific locations, identifying a reduction in diaphragm spasm affected by the delivery of the successive PFA pulses to the specific locations, and determining that, if the reduction in diaphragm spasm exceeds a specific threshold, continued delivery of further PFA pulses to the specific locations may cause irreversible damage to the phrenic nerve; (b) processing motion signals obtained from at least one motion sensor during delivery of a plurality of PFA pulses or pacing signals by the catheter to at least two respective locations of the patient's cardiac tissue to determine spasm degrees associated with the delivery of the PFA pulses or pacing signals to the at least two cardiac tissue locations, respectively, and correlating the spasm degrees with the at least two cardiac tissue locations, thereby mapping diaphragm spasm degrees affected by the delivery of PFA pulses or pacing signals to the two or more cardiac tissue locations.

[0088] Example 17. The system of Example 16, wherein at least one processor is adapted to utilize the mapping in real time during PFA treatment in which PFA pulses are delivered to specific locations of cardiac tissue, to determine, according to the mapping, at least one other tissue location in the vicinity of the specific location that is associated with a reduced degree of spasm relative to the degree of spasm affected by ablation of the specific location, and to issue guide instructions for ablation of the other tissue location.

[0089] Example 18. The system of Example 16 or 17, wherein at least one processor is adapted to utilize mapping to display a map indicating the degree of spasm expected to be affected by ablation of various tissue locations within the region of interest of the cardiac tissue to be ablated.

[0090] Example 19. At least one processor: During a seizure testing phase performed prior to PFA ablation therapy, multiple pacing signals are delivered to at least two respective locations of cardiac tissue; and - The system of any one of Examples 16 to 18, wherein the system is adapted to perform mapping in real time during PFA treatment, at least one of: - a plurality of PFA pulses are delivered to at least two respective locations of the cardiac tissue.

[0091] Example 20. A system described in any one of Examples 16 to 19, wherein the at least one motion sensor includes at least two motion sensors positioned near the left and right sides of the patient's diaphragm to sense diaphragmatic spasms resulting from stimulation of the left or right phrenic nerve by a PFA pulse or pacing signal.

[0092] Example 21 : At least one motion sensor comprises: one or more position sensors, wherein the method includes processing position signals from the one or more position sensors and deriving a movement signal based on a change in position of each of the position sensors; - one or more inertial measurement units (IMUs), adapted to provide motion signals based on inertial measurements performed thereby; one or more accelerometers adapted to provide a movement signal; -A wireless motion sensor including a wireless communication utility capable of wirelessly transmitting signals to a PFA system.

[0093] Example 22. The system of any one of Examples 16 to 21, wherein at least one processor is adapted to process the movement signals to identify seizure-related movement patterns therein and to determine a degree of seizure based on the amplitude of the seizure-related movement patterns in each of the movement signals.

[0094] Example 23. A system according to any one of Examples 16 to 22, adapted for use in at least one of bipolar and monopolar PFA treatments.

[0095] It is to be understood that the above-described embodiments have been cited by way of example, and that the present disclosure is not limited to that particularly shown and described above. Rather, the scope of the present disclosure includes both combinations and subcombinations of the various features described hereinabove, as well as variations and modifications thereof which will occur to those skilled in the art upon reading the description of the present invention and which are not disclosed in the prior art.

[0096] [Embodiment] (1) A method for pulsed field ablation (PFA), comprising: providing a PFA system comprising an ablation catheter and a pulsed field ablation energy generator connectable to one or more ablation electrodes disposed on a distal tip of the catheter and facilitating tissue ablation near the distal tip via delivery of PFA pulses to at least one of the ablation electrodes; providing at least one motion sensor positioned at at least one respective location on the patient's tissue / skin near the patient's diaphragm; The method includes processing motion signals obtained from the at least one motion sensor during a PFA treatment in which multiple successive PFA pulses are delivered to a specific location of cardiac tissue by the one or more electrodes to determine a degree of spasm of the diaphragm caused by the multiple successive PFA pulses delivered to the specific location, identifying a reduction in spasm of the diaphragm affected by the delivery of the successive PFA pulses to the specific location, and determining that continued delivery of additional PFA pulses to the specific location is likely to cause irreversible damage to the phrenic nerve if the reduction in spasm of the diaphragm is identified to exceed a specific threshold. (2) The method of embodiment 1, wherein the at least one motion sensor includes at least two motion sensors positioned near the left and right sides of the patient's diaphragm to sense spasms of the diaphragm due to stimulation of the left or right phrenic nerve by the PFA pulse or pacing signal. (3) The method of embodiment 1, adapted for use in bipolar PFA therapy. (4) the at least one motion sensor one or more position sensors, the method including processing position signals from the one or more position sensors and deriving the motion signal based on changes in position of each of the position sensors; one or more inertial measurement units (IMUs), the one or more IMUs adapted to provide the motion signals based on inertial measurements performed thereby; and one or more accelerometers adapted to provide the movement signal. (5) The method of embodiment 1, wherein the at least one motion sensor is a wireless sensor equipped with a wireless communication utility capable of wirelessly communicating the motion signal to the PFA system.

[0097] (6) A method for pulsed field ablation (PFA), comprising: providing a PFA system comprising: an ablation catheter; a pulsed field ablation energy generator connectable to one or more ablation electrodes disposed at a distal tip of the catheter and facilitating tissue ablation near the distal tip via delivery of PFA pulses to at least one of the ablation electrodes; and a position tracking system connectable to a position sensor disposed near the distal tip of the catheter and adapted to track the position of the one or more ablation electrodes at the distal tip; providing at least one motion sensor positioned near the patient's diaphragm; processing motion signals obtained from the at least one motion sensor during delivery of a plurality of PFA pulses or pacing signals by the catheter to at least two respective locations within the patient's cardiac tissue to determine spasm degrees associated with the delivery of the PFA pulses or pacing signals to the at least two cardiac tissue locations, respectively, and correlating the spasm degrees to the at least two cardiac tissue locations, thereby mapping diaphragm spasm degrees affected by delivery of PFA pulses or pacing signals to two or more cardiac tissue locations. (7) The method of embodiment 6, comprising utilizing the mapping in real time during PFA treatment in which PFA pulses are delivered to a specific location of the cardiac tissue, determining, according to the mapping, at least one other tissue location near the specific location that is associated with a reduced degree of spasm relative to the degree of spasm affected by ablation of the specific location, and issuing guide instructions for ablation of the other tissue location. (8) The method of embodiment 6, comprising utilizing the mapping to display a map indicating the degree of spasm expected to be affected by ablation of various tissue locations within the region of interest of cardiac tissue to be ablated. (9) The mapping is during a seizure testing phase performed prior to PFA ablation therapy, during which the plurality of pacing signals are delivered to the at least two respective locations of the cardiac tissue; and 7. The method of embodiment 6, wherein the method is performed at least one of: in real time during a PFA treatment in which the plurality of PFA pulses are delivered to the at least two respective locations of the cardiac tissue. (10) The method of embodiment 6, wherein the at least one motion sensor includes at least two motion sensors positioned near the left and right sides of the patient's diaphragm to sense spasms of the diaphragm resulting from stimulation of the left or right phrenic nerve by the PFA pulse or pacing signal.

[0098] (11) The method of embodiment 6, adapted for use in bipolar PFA therapy. (12) The at least one motion sensor one or more position sensors, the method including processing position signals from the one or more position sensors and deriving the motion signal based on changes in position of each of the position sensors; one or more inertial measurement units (IMUs), the one or more IMUs adapted to provide the motion signals based on inertial measurements performed thereby; and one or more accelerometers adapted to provide the movement signal. (13) The method of embodiment 6, wherein the at least one motion sensor is a wireless sensor equipped with a wireless communication utility capable of wirelessly communicating the motion signal to the PFA system. (14) A system for pulsed field ablation (PFA), comprising: The system comprises: an ablation catheter having one or more ablation electrodes at a distal end thereof; a position sensor disposed on the ablation catheter that provides data indicative of the position of the distal end of the ablation catheter; at least one motion sensor for coupling to or near at least one region of the subject's body near the patient's diaphragm; a PFA energy generator connectable to the one or more ablation electrodes disposed on the distal end of the ablation catheter and facilitating tissue ablation near the distal end via delivery of PFA pulses to at least one of the ablation electrodes; The system comprises: (a) processing motion signals obtained from the at least one motion sensor during a PFA treatment in which multiple successive PFA pulses are delivered to a specific location of cardiac tissue by the one or more electrodes to determine a degree of spasm of the diaphragm caused by the multiple successive PFA pulses delivered to the specific location; identifying a reduction in spasm of the diaphragm affected by the delivery of the successive PFA pulses to the specific location; and determining, when the reduction in spasm of the diaphragm is identified to exceed a specific threshold, that continued delivery of additional PFA pulses to the specific location may cause irreversible damage to the phrenic nerve; (b) processing motion signals obtained from the at least one motion sensor during delivery of a plurality of PFA pulses or pacing signals by the catheter to at least two respective locations within the patient's cardiac tissue to determine spasm degrees associated with the delivery of the PFA pulses or pacing signals to the at least two cardiac tissue locations, and correlating the spasm degrees with the at least two cardiac tissue locations, thereby mapping diaphragm spasm degrees affected by the delivery of the PFA pulses or pacing signals to two or more cardiac tissue locations. (15) The system of embodiment 14, wherein the at least one processor is adapted to utilize the mapping in real time during PFA treatment in which PFA pulses are delivered to a specific location of the cardiac tissue, to determine, according to the mapping, at least one other tissue location near the specific location that is associated with a reduced spasm level relative to a spasm level affected by ablation of the specific location, and to issue guide instructions for ablation of the other tissue location.

[0099] (16) The system of embodiment 14, wherein the at least one processor is adapted to use the mapping to display a map indicating spasm levels expected to be affected by ablation of various tissue locations within the region of interest of cardiac tissue to be ablated. (17) The at least one processor: during a seizure testing phase performed prior to PFA ablation therapy, during which the plurality of pacing signals are delivered to the at least two respective locations of the cardiac tissue; and 15. The system of embodiment 14, wherein the system is adapted to perform the mapping in at least one of the following: in real time during a PFA treatment in which the plurality of PFA pulses are delivered to the at least two respective locations of the cardiac tissue. (18) The system of embodiment 14, wherein the at least one motion sensor includes at least two motion sensors positioned near the left and right sides of the patient's diaphragm to sense spasms of the diaphragm resulting from stimulation of the left or right phrenic nerve by the PFA pulse or pacing signal. (19) The at least one motion sensor one or more position sensors, the method including processing position signals from the one or more position sensors and deriving the motion signal based on changes in position of each of the position sensors; one or more inertial measurement units (IMUs), the one or more IMUs adapted to provide the motion signals based on inertial measurements performed thereby; one or more accelerometers adapted to provide the movement signals; A system as described in embodiment 14, comprising one or more of: a wireless motion sensor having a wireless communication utility capable of wirelessly communicating the signal to the PFA system. (20) The system of embodiment 14, wherein the at least one processor is adapted to process the movement signals to identify seizure-related movement patterns therein and to determine the degree of seizure based on the amplitude of the seizure-related movement patterns in each of the movement signals.

Claims

1. 1. A system for pulsed field ablation (PFA), comprising: The system comprises: an ablation catheter having one or more ablation electrodes at a distal end; a position sensor disposed on the ablation catheter that provides data indicative of the position of the distal end of the ablation catheter; at least one motion sensor for coupling to or near at least one region of the subject's body near the patient's diaphragm; a PFA energy generator connectable to the one or more ablation electrodes disposed on the distal end of the ablation catheter and facilitating tissue ablation near the distal end via delivery of PFA pulses to at least one of the ablation electrodes; The system comprises: (a) processing motion signals obtained from the at least one motion sensor during a PFA treatment in which a plurality of successive PFA pulses are delivered to a specific location of cardiac tissue by the one or more electrodes to determine a degree of spasm of the diaphragm caused by the plurality of successive PFA pulses delivered to the specific location, identifying a reduction in spasm of the diaphragm affected by the delivery of the successive PFA pulses to the specific location, and determining that continued delivery of additional PFA pulses to the specific location may cause irreversible damage to the phrenic nerve if the reduction in spasm of the diaphragm is identified to exceed a specific threshold; (b) processing motion signals obtained from the at least one motion sensor during delivery of a plurality of PFA pulses or pacing signals by the catheter to at least two respective locations within the patient's cardiac tissue to determine spasm degrees associated with the delivery of the PFA pulses or pacing signals to the at least two cardiac tissue locations, respectively, and correlating the spasm degrees with the at least two cardiac tissue locations, thereby mapping diaphragm spasm degrees affected by the delivery of the PFA pulses or pacing signals to two or more cardiac tissue locations.

2. 2. The system of claim 1, wherein the at least one processor is adapted to utilize the mapping in real time during a PFA treatment in which a PFA pulse is delivered to a specific location of the cardiac tissue, to determine, according to the mapping, at least one other tissue location near the specific location that is associated with a reduced degree of spasm relative to a degree of spasm affected by ablation of the specific location, and to issue guide instructions for ablation of the other tissue location.

3. 2. The system of claim 1, wherein the at least one processor is adapted to utilize the mapping to display a map indicating spasm levels expected to be affected by ablation of various tissue locations within the region of interest of cardiac tissue to be ablated.

4. the at least one processor: during a seizure testing phase performed prior to PFA ablation therapy, during which the plurality of pacing signals are delivered to the at least two respective locations of the cardiac tissue; and 2. The system of claim 1, wherein the system is adapted to perform the mapping at least one of in real time during a PFA treatment in which the plurality of PFA pulses are delivered to the at least two respective locations of the cardiac tissue.

5. 2. The system of claim 1, wherein the at least one motion sensor comprises at least two motion sensors positioned near the left and right sides of the patient's diaphragm to sense spasms of the diaphragm resulting from stimulation of the left or right phrenic nerve by the PFA pulse or pacing signal.

6. the at least one motion sensor one or more position sensors, the method including processing position signals from the one or more position sensors and deriving the motion signal based on changes in position of each of the position sensors; one or more inertial measurement units (IMUs), the one or more IMUs adapted to provide the motion signals based on inertial measurements performed thereby; one or more accelerometers adapted to provide the movement signals; a wireless motion sensor with wireless communication utility capable of wirelessly communicating the signal to the PFA system.

7. 2. The system of claim 1, wherein the at least one processor is adapted to process the movement signals to identify seizure-related movement patterns therein and to determine the degree of seizure based on an amplitude of the seizure-related movement patterns in each of the movement signals.

8. 1. A method for pulsed field ablation (PFA), comprising: providing a PFA system comprising an ablation catheter and a pulsed field ablation energy generator connectable to one or more ablation electrodes disposed on a distal tip of the catheter, the pulsed field ablation energy generator facilitating tissue ablation near the distal tip via delivery of PFA pulses to at least one of the ablation electrodes; providing at least one motion sensor positioned at at least one respective location on the patient's tissue / skin near the patient's diaphragm; The method includes processing motion signals obtained from the at least one motion sensor during a PFA treatment in which multiple successive PFA pulses are delivered to a specific location of cardiac tissue by the one or more electrodes to determine a degree of diaphragm spasm caused by the multiple successive PFA pulses delivered to the specific location, identifying a reduction in diaphragm spasm affected by the delivery of the successive PFA pulses to the specific location, and determining that continued delivery of additional PFA pulses to the specific location may cause irreversible damage to the phrenic nerve if the reduction in diaphragm spasm is identified to exceed a specific threshold.

9. 9. The method of claim 8, wherein the at least one motion sensor comprises at least two motion sensors positioned near the left and right sides of the patient's diaphragm to sense spasms of the diaphragm resulting from stimulation of the left or right phrenic nerve by the PFA pulses or pacing signals.

10. 10. The method of claim 8 adapted for use in bipolar PFA treatment.

11. the at least one motion sensor one or more position sensors, the method including processing position signals from the one or more position sensors and deriving the motion signal based on changes in position of each of the position sensors; one or more inertial measurement units (IMUs), the one or more IMUs adapted to provide the motion signals based on inertial measurements performed thereby; and one or more accelerometers adapted to provide the movement signals.

12. The method of claim 8 , wherein the at least one motion sensor is a wireless sensor with wireless communication utility capable of wirelessly communicating the motion signal to the PFA system.

13. 1. A method for pulsed field ablation (PFA), comprising: providing a PFA system comprising: an ablation catheter; a pulsed field ablation energy generator connectable to one or more ablation electrodes disposed at a distal tip of the catheter and facilitating tissue ablation near the distal tip via delivery of PFA pulses to at least one of the ablation electrodes; and a position tracking system connectable to a position sensor disposed near the distal tip of the catheter and adapted to track the position of the one or more ablation electrodes at the distal tip; providing at least one motion sensor positioned near the patient's diaphragm; processing motion signals obtained from the at least one motion sensor during delivery of a plurality of PFA pulses or pacing signals by the catheter to at least two respective locations within the patient's cardiac tissue to determine spasm degrees associated with the delivery of the PFA pulses or pacing signals to the at least two cardiac tissue locations, respectively, and correlating the spasm degrees to the at least two cardiac tissue locations, thereby mapping diaphragm spasm degrees affected by delivery of PFA pulses or pacing signals to two or more cardiac tissue locations.

14. 14. The method of claim 13, comprising utilizing the mapping in real time during a PFA treatment in which a PFA pulse is delivered to a specific location of the cardiac tissue, determining, according to the mapping, at least one other tissue location near the specific location that is associated with a reduced degree of spasm relative to a degree of spasm affected by ablation of the specific location, and issuing guide instructions for ablation of the other tissue location.

15. 14. The method of claim 13, comprising utilizing the mapping to display a map indicating spasm levels expected to be affected by ablation of various tissue locations within the region of interest of cardiac tissue to be ablated.

16. The mapping during a seizure testing phase performed prior to PFA ablation therapy, during which the plurality of pacing signals are delivered to the at least two respective locations of the cardiac tissue; and 14. The method of claim 13, wherein the method is performed at least one of: in real time during a PFA treatment in which the plurality of PFA pulses are delivered to the at least two respective locations of the cardiac tissue.

17. 14. The method of claim 13, wherein the at least one motion sensor comprises at least two motion sensors positioned near the left and right sides of the patient's diaphragm to sense spasms of the diaphragm resulting from stimulation of the left or right phrenic nerve by the PFA pulses or pacing signals.

18. 14. The method of claim 13 adapted for use in bipolar PFA treatment.

19. the at least one motion sensor one or more position sensors, the method including processing position signals from the one or more position sensors and deriving the motion signal based on changes in position of each of the position sensors; one or more inertial measurement units (IMUs), the one or more IMUs adapted to provide the motion signals based on inertial measurements performed thereby; and one or more accelerometers adapted to provide the movement signals.

20. The method of claim 13 , wherein the at least one motion sensor is a wireless sensor with wireless communication utility capable of wirelessly communicating the motion signal to the PFA system.

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