Cardiac Map Segmentation

Abstract

To provide a cardiac ablation system.SOLUTION: The cardiac ablation system includes: an ablation probe including at least one ablation application element; a tracking module to track a position of the ablation application element; a memory to store a map of the chamber of the heart and store a different, respective default ablation-parameter set for each different region of the chamber; and processing circuitry. The processing circuitry is configured to: segment the map of the chamber into the different regions; receive a user input indicative of commencement of an ablation procedure; identify, responsively to the tracked position, a region of the chamber in contact with the at least one ablation application element; retrieve the respective default ablation-parameter set assigned to the identified region; and apply the retrieved default ablation-parameter set in controlling the ablation procedure.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to ablation systems, and more particularly to ablation parameters. [Background technology]

[0002] Minimally invasive ablation within the heart is a treatment option for various types of arrhythmias. To perform such treatment, a physician typically inserts a catheter into the heart via the vascular system, contacts the distal end of the catheter with myocardial tissue in the area of ​​abnormal electrical activity, and then energizes one or more electrodes at or near the distal end to cause tissue necrosis.

[0003] Numerous systems for intracardiac ablation therapy are commercially available, such as the CARTO® 3 system offered by Biosense Webster Inc. (Irvine, California). CARTO tracks the position and operating parameters of the distal tip of the catheter and electronically displays that information on a three-dimensional (3D) anatomical map of the heart. CARTO allows the system operator to electronically tag ablated locations on the map, thus tracking the progress of the procedure.

[0004] U.S. Patent Publication No. 2015 / 0294082 to Passerini et al. describes a method and system for image-based, patient-specific guidance of cardiac arrhythmia therapy. A patient-specific anatomical cardiac model is generated from the patient's medical image data. A patient-specific cardiac electrophysiology model is generated based on the patient-specific anatomical cardiac model and the patient's electrophysiological measurements. One or more virtual electrophysiological interventions are performed using the patient-specific cardiac electrophysiological model. One or more pacing or ablation targets based on the one or more virtual electrophysiological interventions are displayed.

[0005] U.S. Patent Publication No. 2015 / 0065836 to Thakur et al. describes a system and method for mapping an anatomical structure, including detecting activation signals of physiological activity with a plurality of mapping electrodes disposed within or near the anatomical structure. Patterns among the detected activation signals are identified based on similarity measures generated between each unique pair of identified patterns, which are then classified into groups based on the correlation between the similarity measures of corresponding pairs. A characteristic representation is determined for each group of similarity measures and displayed as a summary plot of the characteristic representation.

[0006] U.S. Patent No. 6,317,631 to Ben-Haim et al. describes a method for modifying the force of contraction of at least a portion of a ventricle, including providing a subject having a heart, at least a portion having activation, and applying, at a delay after activation, a de-energized electric field having a given duration to the portion, increasing the force of contraction by at least 5%. Summary of the Invention [Means for solving the problem]

[0007] According to one embodiment of the present disclosure, there is provided a cardiac ablation system including: an ablation probe including at least one ablation application element configured to ablate tissue within a cardiac chamber of a living subject; a tracking module configured to track the position of the at least one ablation application element within the heart; a memory configured to store a map of the cardiac chamber and to store a different respective default ablation parameter set for each of a plurality of different regions of the chamber; and processing circuitry, wherein the processing circuitry is configured to: segment the map of the chamber into different regions; receive user input indicating initiation of an ablation procedure; identify regions of the chamber in contact with the at least one ablation application element in response to the tracked position; retrieve respective default ablation parameter sets assigned to the identified regions in response to the user input; and apply the retrieved default ablation parameter sets when controlling the ablation procedure.

[0008] Furthermore, in accordance with an embodiment of the present disclosure, the processing circuitry is configured to apply the segmented model of the ventricle to the map of the chamber to yield a segmented map of the chamber.

[0009] Still further, in accordance with an embodiment of the present disclosure, the processing circuitry is configured to receive at least one user correction to the segmentation of the segmented map, and to revise the segmented map in response to the received at least one user correction.

[0010] Further, according to one embodiment of the present disclosure, the processing circuitry is configured to receive user markups of the map of the room to divide the map into different regions and to segment the map of the room into different regions in response to the received user markups.

[0011] Further, in accordance with an embodiment of the present disclosure, the processing circuitry is configured to receive a user-defined default ablation parameter set for each of the different regions, and to assign the user-defined default ablation parameter set to the different regions in response to a region designation for each of the received user-defined default ablation parameter set.

[0012] Furthermore, in accordance with an embodiment of the present disclosure, the processing circuitry is configured to control ablation of tissue in the identified region by the ablation probe according to the retrieved default ablation parameter set.

[0013] Still further, in accordance with an embodiment of the present disclosure, the processing circuitry is configured to receive user updates to the retrieved default ablation parameter set to provide an updated ablation parameter set, and to control ablation of tissue in the identified region by the ablation probe in accordance with the updated ablation parameter set.

[0014] Further, in accordance with an embodiment of the present disclosure, the processing circuitry is configured to assign, for a plurality of different probe types, a probe-specific default ablation parameter set to each of the different regions, and, in response to user input, retrieve, for the probe type of the ablation probe, the probe-specific default ablation parameter set assigned to the identified region.

[0015] Further, according to one embodiment of the present disclosure, the ablation probe includes multiple ablation application elements, and the processing circuitry is configured to: identify, in response to the tracked positions, a first region of the chamber contacted by at least a first element of the multiple ablation application elements; identify, in response to the tracked positions, a second region of the chamber contacted by at least a second element of the multiple ablation application elements; retrieve a default ablation parameter set assigned to the first region and a default ablation parameter set assigned to the second region; and apply the retrieved default ablation parameter sets of the first and second regions to perform an ablation procedure in the first and second regions using the first and second elements of the multiple ablation application elements, respectively.

[0016] Furthermore, according to one embodiment of the present disclosure, the default ablation parameter set for one of the different regions includes any one or more of: tissue thickness of the one region, whether to track temperature during the ablation procedure, an ablation mode to use during the ablation procedure, an irrigation rate to use during the ablation procedure, a power level to apply during the ablation procedure, a force to apply during the ablation procedure, an ablation duration of the ablation procedure, an ablation index to use during the ablation procedure, a target power, and a target temperature.

[0017] Still further, according to an embodiment of the present disclosure, the ablation mode is selected from any one or more of an ablation index mode, controlling ablation power according to the measured temperature, applying an alternating current to at least one ablation application element, applying a direct current to at least one ablation application element, laser ablation, electroporation, cryoablation, and radio frequency power ablation.

[0018] According to another embodiment of the present disclosure, there is also provided a method of cardiac ablation, comprising: tracking the position of at least one ablation application element of an ablation probe configured to ablate tissue in a cardiac chamber of a living subject; storing a different respective default ablation parameter set for each of a plurality of different regions of the chamber; segmenting a map of the chamber into different regions; receiving a user input indicating initiation of an ablation procedure; identifying a region of the chamber in contact with the at least one ablation application element in response to the tracked position; retrieving a respective default ablation parameter set assigned to the identified region in response to the user input; and applying the retrieved default ablation parameter set in controlling the ablation procedure.

[0019] Furthermore, in accordance with an embodiment of the present disclosure, the method includes applying the segmented model of the ventricle to the map of the chamber to yield a segmented map of the chamber.

[0020] Further, in accordance with one embodiment of the present disclosure, the method includes receiving at least one user correction to a segmentation of the segmented map, and amending the segmented map in response to receiving the at least one user correction.

[0021] Further, in accordance with one embodiment of the present disclosure, the method includes receiving user markup of a map of the room to divide the map into different regions, and segmenting the map of the room into different regions in response to receiving the user markup.

[0022] Still further, in accordance with an embodiment of the present disclosure, the method includes receiving a user-defined default ablation parameter set for each of the different regions, and assigning the user-defined default ablation parameter set to the different regions in response to a region designation for each of the received user-defined default ablation parameter set.

[0023] Furthermore, in accordance with an embodiment of the present disclosure, the method includes controlling ablation of tissue in the identified region by the ablation probe according to the retrieved default ablation parameter set.

[0024] Further, in accordance with one embodiment of the present disclosure, the method includes receiving user updates to the retrieved default ablation parameter set to provide an updated ablation parameter set, and controlling ablation of tissue in the identified region by the ablation probe in accordance with the updated ablation parameter set.

[0025] Further, in accordance with one embodiment of the present disclosure, the method includes assigning, for a plurality of different probe types, a probe-specific default ablation parameter set to each of the different regions, and retrieving, in response to user input, the probe-specific default ablation parameter set assigned to the identified region for the probe type of the ablation probe.

[0026] Still further, according to one embodiment of the present disclosure, the ablation probe includes multiple ablation application elements, and the method further includes identifying a first region of the chamber in contact with at least a first element of the multiple ablation application elements in response to the tracked position; identifying a second region of the chamber in contact with at least a second element of the multiple ablation application elements in response to the tracked position; retrieving a default ablation parameter set assigned to the first region and a default ablation parameter set assigned to the second region; and applying the retrieved default ablation parameter sets of the first and second regions to perform an ablation procedure in the first and second regions using the first and second elements of the multiple ablation application elements, respectively.

[0027] Furthermore, according to one embodiment of the present disclosure, the default ablation parameter set for one of the different regions includes any one or more of: tissue thickness of the one region, whether to track temperature during the ablation procedure, an ablation mode to use during the ablation procedure, an irrigation rate to use during the ablation procedure, a power level to apply during the ablation procedure, a force to apply during the ablation procedure, an ablation duration of the ablation procedure, an ablation index to use during the ablation procedure, a target power, and a target temperature.

[0028] Furthermore, according to one embodiment of the present disclosure, the ablation mode is selected from any one or more of the following: an ablation index mode, controlling ablation power according to the measured temperature, applying an alternating current to at least one ablation application element, applying a direct current to at least one ablation application element, laser ablation, electroporation, cryoablation, and radio frequency power ablation.

[0029] According to yet another embodiment of the present disclosure, there is also provided a software product including a non-transitory computer-readable medium having stored thereon program instructions that, when read by a central processing unit (CPU), cause the CPU to: track a position of at least one ablation application element of an ablation probe configured to ablate tissue in a cardiac chamber of a living subject; store a map of the cardiac chamber; store a different respective default ablation parameter set for each of a plurality of different regions of the chamber; segment the map of the chamber into different regions; receive a user input indicating initiation of an ablation procedure; identify a region of the chamber in contact with the at least one ablation application element in response to the tracked position; retrieve a respective default ablation parameter set assigned to the identified region in response to the user input; and apply the retrieved default ablation parameter set in controlling the ablation procedure. [Brief explanation of the drawings]

[0030] The present invention will be understood from the following detailed description taken in conjunction with the accompanying drawings. [Figure 1] 1 is a schematic diagram of an invasive medical procedure using a device, according to one embodiment of the present invention. [Figure 2] 2 is a schematic diagram of the distal end of a probe used in the apparatus of FIG. 1, according to one embodiment of the present invention. [Figure 3] 2 is a flow chart including exemplary steps in a preparation method for use with the device of FIG. 1. [Figure 4] FIG. 2 is a schematic diagram of a map segmentation for use in the apparatus of FIG. 1; [Figure 5] FIG. 2 is a schematic diagram of a region designation for use in the apparatus of FIG. 1; [Figure 6] 2 is a flowchart including exemplary steps in a segmentation and region designation method for use in the apparatus of FIG. 1; [Figure 7] 2 is a flowchart including exemplary steps in an alternative segmentation and region designation method for use in the apparatus of FIG. 1; [Figure 8] 2 is a flow chart including exemplary steps in an ablation method for use with the apparatus of FIG. 1. [Figure 9] FIG. 2 is a schematic diagram of a balloon catheter for use in the apparatus of FIG. 1. [Figure 10] 2 is a cross-sectional view of a balloon catheter disposed within a chamber of the heart for use in the apparatus of FIG. 1. [Figure 11] 2 is a flow chart including exemplary steps in an ablation method using a multi-ablation element probe for use in the apparatus of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0031] Overview During the ablation procedure, the physician can set ablation parameters such as, by way of example only, power, ablation duration, cooling fluid irrigation rate, contact force between the ablation catheter and the tissue being ablated, etc. To set the parameters, the physician must intelligently manage and manually set the required parameter settings without guidance from the ablation device.

[0032] The parameter setting process is time consuming and requires the physician to make decisions regarding the medical problem and control of the ablation device before, during, and after each ablation.

[0033] This process can be prone to error due to the number of decisions required. Additionally, time is generally of the essence in cardiac procedures.

[0034] The above problems can be magnified as ablation devices become more diverse. For example, the catheters may be local ablation catheters or balloon-type catheters, each with its own electrodes. In such situations, setting the ablation parameters can involve taking into account the anatomy of the individual patient, making it more cumbersome and prone to error.

[0035] Embodiments of the present invention provide default ablation parameter sets for use in an ablation procedure according to the tracked position of the ablation probe. So, for example, when the ablation probe is in contact with one region of cardiac tissue, a default ablation parameter set for that region is retrieved for use in the ablation procedure in that region. When the ablation probe is in contact with a second region of cardiac tissue, a different ablation parameter set for the second region is retrieved for use in the ablation procedure in the second region.

[0036] The physician may be provided with the option to modify one or more settings within the retrieved default ablation parameter set before performing an ablation with the ablation probe.

[0037] Prior to initiating the ablation procedure, a map of the patient's cardiac chambers is obtained from an image of the heart (e.g., from a CT or MRI) or from mapping performed using a mapping tool inserted into the patient's ventricles.

[0038] The map of the heart chambers may be automatically segmented by applying the segmented model of the ventricles to the map of the patient's heart chambers, resulting in a segmented map of the patient's heart chambers. The segmented map may also include landmarks that mark various regions of the heart, e.g., the posterior wall, the anterior wall, etc.

[0039] The segmented map may be reviewed by a physician and, if desired, corrected by a physician before use. In some embodiments, the segmented map may be used without prior review.

[0040] In other embodiments, a map of the patient's heart chambers may be segmented based on user markup and labeling of the map, which may be provided by a physician using a suitable user interface.

[0041] Default ablation parameter sets may be assigned to various different regions of the segmented map according to the labeling of the various regions. For example, a default ablation parameter set for the posterior wall is assigned to the region labeled posterior wall. Alternatively, default ablation parameter sets may be manually assigned to different regions by the physician. In other embodiments, default ablation parameter sets may be automatically assigned by the system, with the physician given the option to inspect and correct the various automatically assigned settings.

[0042] The default ablation parameter set for a region may include, by way of example only, any one or more of the tissue thickness of the region, whether to track temperature during the ablation procedure, an ablation mode to use during the ablation procedure, an irrigation rate to use during the ablation procedure, a power level to apply during the ablation procedure, a force to apply during the ablation procedure, an ablation duration of the ablation procedure, an ablation index (described in more detail with reference to FIG. 1 ) to use during the ablation procedure, a target power, and / or a target temperature.

[0043] The ablation mode may be selected from any one or more of, by way of example only, an ablation index mode, controlling ablation power according to a measured temperature, applying an alternating current to at least one ablation application element, applying a direct current to at least one ablation application element, laser ablation, electroporation, cryoablation, and / or radio frequency power ablation.

[0044] For example, a lower power setting may be suggested for the posterior wall than for the anterior wall due to the posterior wall's proximity to the esophagus, which may be thermally damaged during ablation. Similarly, it may be suggested for the posterior wall to perform ablation while adjusting ablation power according to monitored tissue temperature, while it may be suggested for the anterior wall to use an ablation index. Other factors and examples are described in more detail with reference to the system description included below.

[0045] The default ablation parameter sets can be probe-specific, taking into account the different characteristics and capabilities of different ablation probe types. Thus, once a default ablation parameter set for a region is retrieved, a probe-specific default ablation parameter set for that region can be retrieved. For example, a regional catheter may remain at the default settings for the ablation index threshold or temperature-induced ablation settings for the region, while for a balloon catheter, the power settings for the various electrodes can be set based on the region and the current location of each electrode within that region.

[0046] In some embodiments, two or more default ablation parameter sets can be retrieved from the multi-electrode catheter. For example, if some of the electrodes of the multi-electrode catheter are in contact with a first region of tissue while other electrodes of the multi-electrode catheter are in contact with a second region of tissue, the default ablation parameter set for the multi-electrode catheter of the first region and the default ablation parameter set for the multi-electrode catheter of the second region are retrieved for use in ablation using the electrodes in contact with the tissue of the first region and the second region, respectively. The multi-electrode catheters described herein can be generalized to multi-ablation application element catheters that use any suitable ablation method, such as, but not limited to, laser ablation, electroporation, and / or cryoablation. Similarly, the probes described above can utilize any suitable ablation method, such as, but not limited to, laser ablation, electroporation, cryoablation, and / or radiofrequency ablation.

[0047] The default ablation parameter sets can also be adapted to different ablation modes being used by the ablation probe. For example, one default ablation parameter set can be retrieved if the probe is using an ablation index, and another default ablation parameter set can be retrieved if the probe is using a different ablation mode. Alternatively, the default ablation parameter set for each region can be a global parameter set that includes default ablation parameters for multiple ablation modes and / or probes, such that the associated default ablation parameters can be extracted from the global parameter set according to the ablation mode and / or probe type being used.

[0048] Although a physician can override the default settings, embodiments of the present invention automatically add an additional layer of safety without requiring manual intervention.

[0049] System Description Documents incorporated herein by reference are to be considered integral parts of this application, and unless any term is defined in those incorporated documents to the contrary to a definition given herein, either expressly or impliedly, only the definition given herein should be considered.

[0050] Reference is now made to Figure 1, which is a schematic illustration of an invasive medical procedure using cardiac ablation device 12, according to one embodiment of the present invention. Reference is also made to Figure 2, which is a schematic illustration of a distal end 22 of a probe 20 used in device 12, according to one embodiment of the present invention. The procedure is performed by a physician 14, and for the purposes of the following description, it is assumed that the procedure involves ablation of a portion of tissue 15 of myocardium 16 of the heart of a human patient 18.

[0051] To perform the procedure, the physician 14 inserts the probe 20 into a sheath 21 that has been pre-positioned within a lumen of the patient 18 so that the probe 20 is inserted into a chamber of the heart. The sheath 21 is positioned so that a distal end 22 of the probe 20 enters the heart of the patient 18. The distal end 22 includes a position sensor 24 that allows tracking of the location and orientation of the distal end 22, a force sensor 26 that measures the force applied by the distal end 22 when it contacts the myocardium 16, and one or more temperature sensors 28 that measure the temperature at each location of the distal end 22. The distal end 22 further includes one or more electrodes 30 that are used to apply radio frequency power to the myocardium 16 within the heart chamber to ablate the myocardium 16. The electrode(s) 30 may also be used to acquire electrode potentials from the myocardium 16.

[0052] The device 12 is controlled by a system processor 46 located within the device's operator console 48. The operator console 48 includes controls for at least one user input device 49 through which the physician 14 communicates with the processor 46. Software for the processor 46 may be downloaded to the processor 46 in electronic form, for example, over a network. Alternatively, or in addition, the software may be provided on a non-transitory tangible medium, such as an optical, magnetic, or electronic storage medium.

[0053] The processor 46 may include a real-time noise reduction circuit 45, typically configured as a field programmable gate array (FPGA), followed by an analog-to-digital (A / D) signal conversion integrated circuit 47. The processor 46 may communicate signals from the A / D signal conversion integrated circuit 47 to another processor and / or may be programmed to execute at least one algorithm disclosed herein, including steps described herein below. To execute the algorithm, the processor 46 uses the noise reduction circuit 45 and the A / D signal conversion integrated circuit 47, as well as functional portions of modules described in more detail below. The memory 43 is configured to store data used by the processor 46.

[0054] To operate device 12, algorithms in processor 46 communicate with a module bank 50 having a number of modules used by processor 46 to operate device 12. Thus, module bank 50 includes an electrocardiogram (ECG) module 56 coupled to receive signals from body surface electrodes 31 and / or electrodes 30 to provide ECG signals to processor 46. Body surface electrodes 31 and / or electrode(s) 30 are configured to be applied to the body of a subject (e.g., patient 18) and configured to output signals in response to electrical activity of the subject's heart. Electrode(s) 30 are applied to the body's heart via probe 20. Module bank 50 also includes a tracking module 58 that receives and analyzes signals from position sensor 24 and uses the signal analysis to generate a location and orientation of distal end 22. In some embodiments, position sensor 24 includes one or more coils that provide a sensor signal in response to a magnetic field across the coils. In these embodiments, the tracking module 58, in addition to receiving and analyzing signals from the position sensor 24, controls the emitters 32, 34, and 36, which emit magnetic fields across the position sensor 24. The emitters 32, 34, and 36 are positioned proximate the myocardium 16 and configured to emit alternating magnetic fields into a region proximate the myocardium 16. A plurality of wire connections 35 couple the operation console 48 to the body surface electrodes 31 and other components (such as the emitters 32, 34, 36 and the sensor 24) to enable the tracking module 58 to measure location and orientation coordinates of the probe 20. In some embodiments, the tracking module 58 is configured to calculate the relative location and orientation of the probe 20 with respect to the heart. Magnetic location and orientation tracking is described in U.S. Patent Nos. 7,756,576 and 7,536,218, both of which are incorporated herein by reference. The CARTO system, manufactured by Biosense Webster, Inc. (33 Technology Drive, Irvine, CA 92618 USA), uses a magnetic tracking system such as that described above. Tracking module 58 is not limited to using magnetic-based location and orientation tracking.Any suitable location and orientation tracking may be used, such as impedance-based tracking or image-based tracking.

[0055] The device 12 includes an image processor, which may be incorporated into or called by the processor 46, that can receive image data from an external imaging modality, such as an MRI unit, a CT unit, etc., and generate and display images. The image data may be registered with a tracking module 58, and a user interface screen 70 combining the received data with the position of the probe 20 may be displayed on the display 61 for the physician 14. For example, the trajectory of the distal end 22 of the probe 20 may be shown on a three-dimensional (3D) representation of the heart of the patient 18 displayed on the display 61. In some embodiments, the 3D representation of the heart may be calculated at least in part based on mapping performed by the probe 20.

[0056] The electrode(s) 30 and body surface electrodes 31 may be used to measure tissue impedance at the ablation site as taught in U.S. Patent No. 7,536,218 issued to Govari et al., which is incorporated herein by reference.

[0057] Module bank 50 also includes a force module 60, a power supply module 62, an irrigation module 64, and a temperature module 66. The functions of these modules are described below. The modules in module bank 50 and processor 46 are referred to herein as processing circuitry 51.

[0058] Force module 60 receives signals from force sensor 26 and generates from the signals a magnitude of the contact force (assumed to be measured in grams herein) exerted by distal end 22 on tissue 15. In some embodiments, force sensor 26 is configured such that the signals it provides to force module 60 enable force module 60 to assess the direction of the force exerted by distal end 22 on tissue 15.

[0059] The power supply module 62 includes a radio frequency (RF) signal generator 63 that generates radio frequency power that is applied by the electrode(s) 30 to ablate tissue 15 of the myocardium 16. The processor 46 and power supply module 62 are capable of adjusting the power level (assumed herein measured in watts) delivered by the electrode(s) 30 and the length of time, measured in seconds, during which the power is delivered.

[0060] Irrigation module 64 controls the flow rate (assumed herein measured in mL / min) of irrigation fluid, typically saline, supplied to distal end 22 by pump 65 disposed within operator console 48. Probe 20 includes irrigation channels therethrough for irrigating myocardium 16. Irrigation fluid is emitted through irrigation holes 69 at distal end 22. Pump 65 is configured to selectively pump irrigation fluid into the irrigation channels at an idle speed and at one or more non-idle speeds (higher than the idle speed) according to the status of the ablation procedure.

[0061] The temperature module 66 receives the temperature signals provided by the temperature sensor 28 (or by each temperature sensor 28). The temperature signals are indicative of the temperature of the myocardium at multiple different times. The temperature module 66 determines the temperature registered by each of the sensors 28. Typically, in the case of multiple sensors 28, the temperature module 66 determines the average temperature at the distal tip 22. Additionally, if multiple sensors are present, the temperature module 66 can create a map of the temperature distribution at the distal tip 22.

[0062] Ablation may be performed according to, for example, but not limited to, an ablation index mode, or any suitable ablation mode in which the ablation power and / or irrigation rate is modified according to the temperature or rate of change of temperature measured by temperature sensor 28 or another temperature sensor disposed in any suitable location. Both of these modes are described in more detail below. In addition to RF ablation, device 12 may also be modified to perform non-RF ablation or another type of ablation, for example, but not limited to, laser ablation, electroporation, and / or cryoablation.

[0063] As known in the art, the Ablation Index is a function whose value changes as the ablation progresses and provides an estimate of the size of the lesion caused by the ablation of a known type of tissue. The estimate provided by this index depends on the values ​​of contact force CF and power P measured during and over the time of ablation. The Ablation Index is described in an article by Hussein et al. entitled "Ablation Index-guided Pulmonary Vein Isolation for Atrial Fibrillation may Improve Clinical Outcomes in Comparison to Contact Force-guided Ablation," published at the 2016 Heart Rhythm Congress, and in U.S. Patent Application No. 2017 / 0014181 by Bar-Tal et al., both of which are incorporated herein by reference.

[0064] The following equation (1) represents the ablation index.

[0065]

number

[0066] Assuming that the contact force and power are constant, their respective values ​​during the ablation procedure, which takes time t,

[0067]

number

[0068]

number

[0069] If the value on the left side of equation (2), the tissue thickness D, is known (from estimation, a scan, or other calculation), processor 46 can use the right side of equation (2) to provide physician 14 with recommended values ​​of power P and time t for ablation using the measured value of force CF and the estimated value of C. Physician 14 can select one of the recommended values ​​of power P and time t to ablate tissue 15 and finish ablating tissue 15 at those values.

[0070] The ablation index serves as an aid to the physician in determining the values ​​of parameters such as ablation power and duration to be used during the ablation procedure.

[0071] Pending patent application Ser. No. 16 / 196,255 to Govari et al., filed Nov. 20, 2018, describes adjusting power and irrigation according to measured temperature and rate of change of temperature. Exemplary functions for calculating irrigation rate and power change for each cycle of multiple cycles are now described below.

[0072] New Perfusion Rate (Flow) = currentFlow + deltaFlow(Temp) + deltaFlow(Power) (Equation 1), where: currentFlow is the current perfusion rate, deltaFlow(Temp)=At * ΔT+Bt * TempSlope+Ct * ∫ΔT+Dt * avg(ΔT), and deltaFlow(Power)=Ap * ΔP+Bp * PowerSlope+Cp * ∫ΔP+Dp * avg(ΔP), ΔT is the difference between TargetTemp and Temp (the sampled temperature, which can be the average value over several sample cycles); TempSlope is equal to the rate of change of the sampled temperature and can be calculated from the averaged samples. ∫ΔT is the integral of ΔT, and the integral time range may vary; avg(ΔT) is the average value of ΔT, At is the adjustment parameter for ΔT, Bt is the adjustment parameter for TempSlope, Ct is an adjustment parameter for ∫ΔT, Dt is an adjustment parameter for avg(ΔT), ΔP is the difference between TargetPower and Power (sampled power, which can be an average value over several sample cycles), PowerSlope is the rate of change of the sampled power, which can be calculated from averaged samples, ∫ΔP is the integral of ΔP, and the integration time range may vary; avg(ΔP) is the average value of ΔP, Ap is an adjustment parameter for ΔP, Bp is the adjustment parameter for PowerSlope, Cp is an adjustment parameter for ∫ΔP, Dp is an adjustment parameter for avg(ΔP).

[0073] The initial perfusion rate (flow rate) can be calculated as follows: Flow rate=FlowLow+(FlowHigh-FlowLow) / (PowerHigh-PowerLow) * (TargetPower-PowerLow) (Equation 2), where: FlowLow is the lowest perfusion rate provided by the system. FlowHigh is the highest perfusion rate provided by the system. PowerLow is the lowest power provided by the system, PowerHigh is the highest power provided by the system.

[0074] Exemplary ranges and values ​​for various parameters are provided below, however, it should be noted that the values ​​may be any suitable value, even outside the ranges provided below.

[0075] [Table 1]

[0076] The above example ranges and values ​​assume that ΔT is equal to TargetTemp (target temperature) minus Temp (sampled temperature) and ΔP is equal to TargetPower (target power) minus Power (sampled power). The example ranges and values ​​given above for integral refer to example upper limits for integral, with the lower limit for integral being zero seconds. The example ranges and values ​​for Avg(ΔT) and Avg(ΔP) refer to example sampling time ranges for calculating the average.

[0077] Note that the parameters may be floating point numbers, and any of the parameters may be averaged over a period of time that may vary, if desired. The new perfusion rate may be a floating point number with a limited range.

[0078] In some embodiments, the ablation power can be varied so as to maintain a target temperature as measured by the temperature sensor(s). Varying different ablation parameters according to the measured temperature is sometimes referred to as "temperature-induced ablation."

[0079] The following discussion, with reference to FIGS. 3-11 , describes various exemplary methods for providing a default ablation parameter set for use in an ablation procedure. The ablation procedure may be performed using the device 12 and probe 20 as described above with reference to FIGS. 1 and 2 , or may be performed using the device 12 with various modifications to the probe 20 and operation console 48, e.g., using a different type of ablation probe including one or more ablation electrodes, or using a different ablation method in addition to or instead of RF ablation. Additional ablation methods may include, by way of example only, laser ablation, electroporation, and / or cryoablation. The ablation probe 20 may include at least one ablation application element configured to ablate tissue 15 within a cardiac chamber of a living subject (e.g., patient 18). The one or more ablation application elements may include, by way of example only, an ablation electrode, a laser device, and / or a refrigerant tube. Ablation probe 20 may optionally include one or more of a force sensor, a temperature sensor, a position sensor, and an irrigation system, as described above with reference to Figures 1 and 2. In other embodiments, ablation probe 20 may include other sensors in addition to or instead of the sensors described above with reference to Figures 1 and 2. In some embodiments, ablation probe 20 may not include an irrigation system.

[0080] Reference is now made to FIG. 3, which is a flow chart 70 including exemplary steps in a preparation method for use in the device 12 of FIG.

[0081] Processor 46 is configured to store (block 72) a map of the heart chamber in memory 43 (FIG. 1). The map may be derived from CT, MRI, or other imaging techniques, or from mapping provided using a mapping probe inside the heart chamber.

[0082] Processor 46 is configured to segment the map of the room into different regions (block 74). Segmenting the map may be performed automatically, semi-automatically, or manually. Segmenting the map is described in more detail with reference to Figures 4-7.

[0083] Processor 46 is configured to assign a default ablation parameter set to each of the different regions (block 76). In some embodiments, each default ablation parameter set may include default ablation parameters for a different probe type and / or a different ablation mode used by ablation probe 20. In other embodiments, processor 46 is configured to assign probe-specific default ablation parameter sets to each of the different regions for multiple different probe types. The default ablation parameter sets may also be adapted to different ablation modes used by the ablation probe. For example, one default ablation parameter set may be retrieved if the probe uses an ablation index, and another default ablation parameter set may be retrieved if the probe uses a different ablation mode. Assigning default ablation parameter sets to different regions is described in more detail with reference to FIG. 6.

[0084] The default ablation parameter set for one of the different regions may include, by way of example only, any one or more of the tissue thickness of the region, whether to track temperature during the ablation procedure, an ablation mode to use during the ablation procedure, an irrigation rate to use during the ablation procedure, a power level to apply during the ablation procedure, a force to apply during the ablation procedure, an ablation duration of the ablation procedure, an ablation index to use during the ablation procedure, a target power, and / or a target temperature.

[0085] The ablation mode may be selected from any one or more of, by way of example only, an ablation index mode, controlling ablation power according to a measured temperature, applying an alternating current to at least one ablation application element, applying a direct current to at least one ablation application element, laser ablation, electroporation, cryoablation, and / or radio frequency power ablation.

[0086] As an example, the ablation power applied near the posterior wall may be adjusted according to the temperature measured either by the probe or using a sensor disposed near the esophagus. Thus, a temperature-driven ablation mode may be more suitable for the posterior wall, while other ablation methods, e.g., ablation index, may be used for other regions of the chamber. As another example, appendage ablation should be avoided whenever possible, so the power or ablation index in that region may be set to a low value. As another example, the ablation index value may be set higher for the anterior wall and lower for the posterior wall. Generally, the ablation index value may be set according to the estimated or actual thickness of tissue in each region. By way of example only, the irrigation rate may also be set to a higher value for the posterior wall compared to other regions. Generally, ablation techniques may be region-dependent, such that the most effective ablation mode for a particular region is included in the default ablation parameter set for that region.

[0087] For example, different default settings for the back wall, front wall, and lid regions may be as follows: Posterior wall - ablation power 90W, ablation duration 4 seconds, contact force ≥2g, Anterior wall—ablation power of 35 W, ablation index threshold of 550 units, irrigation rate of 15 ml / sec, and contact force of 5 g or greater; Lid - 45W ablation power, 450 units ablation index threshold, 15ml / sec irrigation rate, 5g or more contact force.

[0088] Because some probes may be capable of performing a given ablation mode (e.g., temperature-induced ablation) while others cannot, the default ablation parameters can be adapted as described above for different probe types. Some probes may include elements (e.g., irrigation systems, lasers, or refrigerant tubing) while others cannot.

[0089] Default ablation parameters for multiple ablation elements (e.g., a balloon catheter with multiple electrodes) may provide different default settings for different ones of the ablation elements. In some embodiments, the default settings for different ablation elements may include different ablation elements performing ablation in different ablation modes. A further example is provided with reference to FIG. 11 .

[0090] The processor 46 is configured to store in the memory 43 (block 78) a different respective default ablation parameter set for each of a plurality of different regions of the chamber (and optionally each probe type), and to provide a link between the default ablation parameter set and the region (and probe type).

[0091] Reference is now made to FIG. 4, which is a schematic diagram of map segmentation for use in apparatus 12 of FIG. 1. FIG. 4 illustrates an anterior view 80 and a posterior view 82 of a map 84 of a heart chamber before and after segmentation into different regions 88 (only portions labeled for simplicity). The anterior view 80 and the posterior view 82 may be rendered by processor 46 for display on display 61 ( FIG. 1 ) or any other suitable display. The anterior view 80 and the posterior view 82 of map 84 may be rendered as two separate two-dimensional (2D) images or as part of a rotatable three-dimensional (3D) image that includes both the anterior view 80 and the posterior view 82. Processor 46 receives user markup 86 via input device 49 ( FIG. 1 ) and updates map 84 with the user markup 86. The user markup 86 divides map 84 into different regions 88 (only portions labeled for simplicity) at region boundaries 90.

[0092] Reference is now made to FIG. 5, which is a schematic illustration of region designations for use with the apparatus 12 of FIG. 1. The segmented map 84 is then rendered by the processor 46 for display on the display 61. The physician 14 (FIG. 1) can then add labels (e.g., operculum, septum, mitral valve, etc.) and provide region designations 92 for each of the regions 88 using the input device 49. The labels may be selected from pre-populated lists (e.g., pull-down lists) and / or based on free-form text. The regions 88 listed in FIG. 5 are for the left atrium, by way of example only. The chamber may be divided into more or fewer regions 88 than shown in FIG. 5. FIGS. 4 and 5 are described with reference to the left atrium. The method may also be implemented for any suitable ventricle.

[0093] Reference is now made to FIG. 6, which is a flowchart 100 including exemplary steps in a segmentation and region designation method for use in the apparatus 12 of FIG.

[0094] The processor 46 (FIG. 1) is configured to display the map 84 on the display 61 (FIG. 1) (block 102). The processor 46 is configured to receive user markups 86 (FIG. 4) of the room map 84 via the input device 49 (FIG. 1) (block 104) and divide the map 84 into different regions 88 (FIGS. 4 and 5). The processor 46 is configured to segment the room map 84 into different regions 88 (block 106) in response to the received user markups 86. The processor 46 is configured to display the segmented map 84 (block 108). If the map needs to be corrected, the physician 14 can re-input the corrected markups (arrow 110) in the step of block 104. The processor 46 is configured to receive region designations 92 (FIG. 5) of the different regions 88 of the map 84 designated by the physician 14 (block 112). Processor 46 is configured to assign region designation 92 to region 88 of map 84 (block 114).

[0095] As described herein below, default ablation parameters can be assigned to each of the regions 88 automatically, semi-automatically, or manually.

[0096] In automatic mode, processor 46 is configured to automatically assign (block 116) default ablation parameter sets to regions 88 based on the region designation 92 of each of regions 88. For example, a previously stored default ablation parameter set for the septum can be assigned to the septum region, or a previously stored default ablation parameter set for a LUPV region for a balloon catheter can be assigned to a LUPV region for use with a balloon catheter.

[0097] In the semi-automatic mode, processor 46 is configured to display on display 61 (block 118) default ablation parameter sets automatically assigned to regions 88 based on the region designations 92 of each of regions 88, as described with reference to the step of block 116. Physician 14 can then review the automatically assigned default ablation parameter sets and update the default ablation parameter sets using input device 49. Processor 46 is configured to receive user updates to the default ablation parameter sets (block 120) and revise the default ablation parameter sets in accordance with the user updates (block 122).

[0098] In manual mode, processor 46 is configured to receive (block 124) a user-defined default ablation parameter set for each of the different regions 88 defined by physician 14. Processor 46 is configured to assign the user-defined default ablation parameter set to the different regions 88 in response to the region designation of each of the received user-defined default ablation parameter sets.

[0099] Reference is now made to FIG. 7, which is a flowchart 130 including exemplary steps in an alternative segmentation and region designation method for use with the apparatus 12 of FIG. 1. FIG. 7 illustrates an automatic and semi-automatic method for segmenting the map 84 (FIGS. 4 and 5) based on a segmented model of the ventricle. The processor 46 (FIG. 1) is configured to apply the segmented model of the ventricle to the map 84 of the chamber (block 132), resulting in the segmented map 84 of the chamber. The segmented model typically includes a segmented and labeled ventricle map previously prepared by a medical professional, or is based on comparing previously segmented and labeled ventricle maps prepared by one or more medical professionals. The processor 46 may use image processing techniques, including scaling the model vertically and horizontally and, optionally, moving the perimeter of the ventricle model, until the model matches the map 84. The processor 46 then applies the model's region boundary to the map 84, resulting in the segmented map 84 of the chamber. Processor 46 is configured to apply the region designations of the regions contained within the model to corresponding regions 88 of map 84 (block 134).

[0100] According to some embodiments, processor 46 is configured to display segmented map 84 with region designations, if desired (block 136). Physician 14 can then examine map 84 to determine whether corrections to region boundaries 90 and / or region designations 92 are necessary. Processor 46 is configured to receive at least one user correction to the segmentation and / or region designations 92 from input device 49 (block 138). Processor 46 is configured to revise the segmentation and / or region designations 92 of map 84 in response to the user correction(s) (block 140). Processor 46 is configured to display the corrected segmented map 84 (block 142). The steps of blocks 138-142 may be repeated to provide subsequent user corrections (arrow 144).

[0101] Default ablation parameters may be assigned to each of the regions 88 automatically, semi-automatically, or manually, as described above with reference to the steps of blocks 116-126 of FIG.

[0102] Reference is now made to Figure 8, which is a flow chart 150 including exemplary steps in an ablation method for use with the apparatus 12 of Figure 1. After performing the preparation method described above with reference to Figure 3 and in more detail with reference to Figures 4-7, the ablation procedure can begin. Preparation of the ablation probe 20 and its insertion into a cardiac chamber of the patient 18 has been described in detail with reference to Figure 1.

[0103] Tracking module 58 is configured to track (block 152) the position of the ablation application element(s) of ablation probe 20 within the heart. Tracking module 58 was described in more detail with reference to FIG.

[0104] The processor 46 is configured to receive user input (e.g., via the input device 49) indicating the initiation of an ablation procedure (block 154). The processor 46 is configured to identify (block 156) a region of the chamber in contact with the ablation application element(s) in response to the tracked positions. For example, the ablation application element(s) may be in contact with the left atrial septum. In response to the user input in the step of block 154, the processor 46 is configured to retrieve (block 158) a respective default ablation parameter set assigned to the identified region. For example, a default ablation parameter set for the left atrial septum is retrieved. In some embodiments, in response to the user input in the step of block 154, the processor 46 is configured to retrieve a probe-specific default ablation parameter set assigned to the identified region for a probe type of ablation probe. For example, a default ablation parameter set for the left atrial septum for a balloon catheter is retrieved.

[0105] Processor 46 is configured to apply the retrieved default ablation parameter set when controlling the ablation procedure (block 160). The step of block 160 may include automatically accepting the retrieved default ablation parameter set when controlling the ablation procedure or allowing a user (e.g., physician 14) to review and revise the retrieved settings before using the settings in the ablation procedure, as described in more detail below with reference to the steps of blocks 162 and 164.

[0106] Thus, in some embodiments, processor 46 is configured to display the retrieved default ablation parameter set on display 61 (block 162) and receive user updates to the retrieved default ablation parameter set via input device 49 (block 164) to result in an updated ablation parameter set. Processor 46 is configured to control ablation by ablation probe 20 of tissue in the identified region in accordance with the retrieved default ablation parameter set (or in accordance with the updated ablation parameter set, if the step of block 164 was performed) (block 166).

[0107] Reference is now made to Figure 9, which is a schematic diagram of a balloon catheter 168 for use in the apparatus 12 of Figure 1. The balloon catheter 168 is an ablation probe that includes multiple ablation application elements 170 (e.g., ablation electrodes) disposed about the equator of an inflatable balloon 172 of the balloon catheter 168. The balloon catheter 168 is particularly effective in simultaneously performing ablations at two or more sites within a chamber of the heart.

[0108] Reference is now made to FIG. 10 , which illustrates a cross-sectional view of a balloon catheter 168 disposed within a cardiac chamber for use with the device 12 of FIG. 1 . Some of the ablation application elements 170-1 are contracted with a first tissue surface 174 of the chamber, some of the ablation application elements 170-2 are in contact with a second tissue surface 176 of the chamber, and some of the ablation application elements 170-3 are not in contact with any tissue. Furthermore, the tissue 178 of the first tissue surface 174 is thicker than the tissue 180 of the second tissue surface 176. Therefore, when activating the balloon catheter 168 to perform ablation, the ablation application element 170-1 should be set for a higher power and / or a longer ablation duration than the ablation application element 170-2, but the ablation application element 170-3 should not be activated at all. Applying these settings can be very difficult for the physician 14.

[0109] According to some embodiments of the present invention, different default ablation parameter sets are retrieved for ablation application element 170-1 in contact with first tissue surface 174 and ablation application element 170-2 in contact with second tissue surface 176 based on the tracked location of each of the ablation application elements 170. Ablation application element 170-3 that is not currently in contact with any tissue is generally not activated to prevent additional heat generation within the ventricle. The above method will now be described in more detail with reference to FIG. 11.

[0110] Reference is now made to FIG. 11, which is a flowchart 182 including exemplary steps in an ablation method using a multi-ablation element probe (e.g., balloon catheter 168 of FIG. 9, or any other suitable multi-ablation element probe) for use with the apparatus of FIG. 1.

[0111] Tracking module 58 is configured to track the position of each of the ablation application elements of the multi-ablation element probe within the heart (block 184). Processor 46 is configured to receive user input (e.g., via input device 49) indicating the start of an ablation procedure (block 186).

[0112] Processor 46 is configured to identify, in response to the tracked position of each of the ablation application elements, an area 88 of the chamber in contact with the ablation application element (block 188).

[0113] For example, processor 46 is configured to identify a first region of the chamber (e.g., first tissue surface 174) in contact with at least a first element of the multiple ablation application elements (e.g., ablation application element 170-1 of FIG. 10) in response to the tracked positions. Processor 46 is configured to identify a second region of the chamber (e.g., second tissue surface 176) in contact with at least a second element of the multiple ablation application elements (e.g., ablation application element 170-2 of FIG. 10) in response to the tracked positions.

[0114] Processor 46 is configured to retrieve (block 190) a default ablation parameter set assigned to each of the identified regions (e.g., a default ablation parameter set assigned to the first region and a default ablation parameter set assigned to the second region).

[0115] The processor 46 is configured to apply (block 192) the retrieved default ablation parameter sets (e.g., the retrieved default ablation parameter sets for the first and second regions) to perform an ablation procedure in the identified regions (e.g., the first and second regions) using corresponding ablation application elements (e.g., the first and second elements of the multiple ablation application elements, respectively).

[0116] The steps of blocks 194 and 196 broadly correspond to the steps of blocks 162 and 164, respectively, described above with reference to Figure 8. Processor 46 is configured to control ablation (block 198) in accordance with the retrieved (or updated) default ablation parameter set.

[0117] Various features of the invention, which are, for clarity, described in the context of multiple separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination.

[0118] The above-described embodiments are cited by way of example, and the present invention is not limited to what has been particularly shown and described above. Rather, the scope of the present invention includes both combinations and sub-combinations of the various features described above, as well as variations and modifications thereof not disclosed in the prior art that would occur to one skilled in the art upon reading the foregoing description.

[0119] [Embodiment] (1) A cardiac ablation system, comprising: an ablation probe including at least one ablation application element configured to ablate tissue within a cardiac chamber of a living subject; a tracking module configured to track a position of the at least one ablation element within the heart; a memory configured to store a map of the chamber of the heart and to store a different respective default ablation parameter set for each of a plurality of different regions of the chamber; and processing circuitry, said processing circuitry comprising: segmenting the map of the room into the different regions; receiving a user input indicating the initiation of an ablation procedure; identifying an area of ​​the chamber in contact with the at least one ablation application element in response to the tracked position; retrieving the respective default ablation parameter sets assigned to the identified regions in response to the user input; and applying the retrieved default ablation parameter set in controlling the ablation procedure. (2) The system of embodiment 1, wherein the processing circuitry is configured to apply a segmented model of the ventricle to the map of the chamber to produce a segmented map of the chamber. (3) the processing circuitry: receiving at least one user correction to a segmentation of the segmented map; and revising the segmented map in response to the received at least one user correction. (4) the processing circuitry: receiving a user markup of the map of the room to divide the map into the different regions; The system of embodiment 1, configured to segment the map of the room into the different regions in response to the received user markup. (5) the processing circuitry: receiving a user-defined default ablation parameter set for each of the different regions; The system of embodiment 1, configured to assign the user-defined default ablation parameter sets to the different regions in response to a region designation for each of the received user-defined default ablation parameter sets.

[0120] (6) The system of embodiment 1, wherein the processing circuitry is configured to control ablation of the tissue in the identified region by the ablation probe according to the retrieved default ablation parameter set. (7) The processing circuitry receiving user updates to the retrieved default ablation parameter set to provide an updated ablation parameter set; 2. The system of claim 1, wherein the system is configured to control ablation of the tissue in the identified region by the ablation probe according to the updated ablation parameter set. (8) The processing circuitry assigning, for a plurality of different probe types, a probe-specific default ablation parameter set to each of the different regions; The system of embodiment 1, configured to retrieve, in response to the user input, a probe-specific default ablation parameter set assigned to the identified region for the probe type of the ablation probe. (9) the ablation probe includes multiple ablation application elements; the processing circuitry identifying a first region of the chamber contacted by at least a first of the multiple ablation application elements in response to the tracked location; identifying a second region of the chamber contacted by at least a second of the multiple ablation application elements in response to the tracked location; retrieving the default ablation parameter set assigned to the first region and the default ablation parameter set assigned to the second region; The system of embodiment 1, wherein the system is configured to apply the retrieved default ablation parameter sets of the first and second regions to perform the ablation procedure in the first and second regions using the first and second elements of the multiple ablation application elements, respectively. (10) The system of embodiment 1, wherein the default ablation parameter set for one of the different regions includes any one or more of the tissue thickness of the one region, whether to track temperature during the ablation procedure, an ablation mode to use during the ablation procedure, an irrigation rate to use during the ablation procedure, a power level to apply during the ablation procedure, a force to apply during the ablation procedure, an ablation duration of the ablation procedure, an ablation index to use during the ablation procedure, a target power, and a target temperature.

[0121] (11) The system of embodiment 10, wherein the ablation mode is selected from any one or more of an ablation index mode, controlling ablation power according to a measured temperature, applying an alternating current to the at least one ablation application element, applying a direct current to the at least one ablation application element, laser ablation, electroporation, cryoablation, and radiofrequency power ablation. (12) A cardiac ablation method, comprising: Tracking the position of at least one ablation application element of an ablation probe configured to ablate tissue within a cardiac chamber of a living subject; storing a map of the chambers of the heart; storing a different respective default ablation parameter set for each of a plurality of different regions of the chamber; segmenting the map of the room into the different regions; receiving a user input indicating the initiation of an ablation procedure; identifying an area of ​​the chamber in contact with the at least one ablation application element in response to the tracked position; retrieving the respective default ablation parameter sets assigned to the identified regions in response to the user input; and applying the retrieved default ablation parameter set in controlling the ablation procedure. (13) The method of embodiment 12, further comprising applying a segmented model of the ventricle to the map of the chamber to produce a segmented map of the chamber. (14) receiving at least one user correction to the segmentation of the segmented map; 14. The method of claim 13, further comprising: revising the segmented map in response to receiving the at least one user correction. (15) receiving user markup of the map of the room to divide the map into the different regions; 13. The method of claim 12, further comprising: segmenting the map of the room into the different regions in response to receiving the user markup.

[0122] (16) receiving a user-defined default ablation parameter set for each of the different regions; 13. The method of claim 12, further comprising: assigning the user-defined default ablation parameter sets to the different regions in response to a region designation for each of the received user-defined default ablation parameter sets. (17) The method of embodiment 12, further comprising controlling ablation of the tissue in the identified region by the ablation probe according to the retrieved default ablation parameter set. (18) receiving user updates to the retrieved default ablation parameter set to provide an updated ablation parameter set; 13. The method of claim 12, further comprising: controlling ablation of the tissue in the identified region by the ablation probe according to the updated ablation parameter set. (19) for a plurality of different probe types, assigning a probe-specific default ablation parameter set to each of the different regions; 13. The method of claim 12, further comprising: retrieving, in response to the user input, a probe-specific default ablation parameter set assigned to the identified region for a probe type of the ablation probe. (20) The ablation probe includes multiple ablation application elements; The method comprises: identifying a first region of the chamber contacted by at least a first of the multiple ablation application elements in response to the tracked location; identifying a second region of the chamber contacted by at least a second of the multiple ablation application elements in response to the tracked location; retrieving the default ablation parameter set assigned to the first region and the default ablation parameter set assigned to the second region; 13. The method of claim 12, further comprising applying the retrieved default ablation parameter sets for the first and second regions to perform the ablation procedure in the first and second regions using the first and second elements of the multiple ablation application elements, respectively.

[0123] (21) The method of embodiment 12, wherein the default ablation parameter set for one of the different regions includes any one or more of: a tissue thickness of the one region; whether to track temperature during the ablation procedure; an ablation mode to use during the ablation procedure; an irrigation rate to use during the ablation procedure; a power level to apply during the ablation procedure; a force to apply during the ablation procedure; an ablation duration of the ablation procedure; an ablation index to use during the ablation procedure; a target power; and a target temperature. (22) The method of embodiment 21, wherein the ablation mode is selected from any one or more of an ablation index mode, controlling ablation power according to a measured temperature, applying an alternating current to the at least one ablation application element, applying a direct current to the at least one ablation application element, laser ablation, electroporation, cryoablation, and radiofrequency power ablation. (23) A software product including a non-transitory computer-readable medium having stored thereon program instructions, the instructions, when read by a central processing unit (CPU), causing the CPU to: Tracking the position of at least one ablation application element of an ablation probe configured to ablate tissue within a cardiac chamber of a living subject; storing a map of the chambers of the heart; storing a different respective default ablation parameter set for each of a plurality of different regions of the chamber; segmenting the map of the room into the different regions; receiving a user input indicating the initiation of an ablation procedure; identifying an area of ​​the chamber in contact with the at least one ablation application element in response to the tracked position; retrieving the respective default ablation parameter sets assigned to the identified regions in response to the user input; and applying the retrieved default ablation parameter set in controlling the ablation procedure.

Claims

1. 1. A cardiac ablation system comprising: an ablation probe including at least one ablation application element configured to electrically ablate tissue within a cardiac chamber of a living subject; a tracking module configured to track a position of the at least one ablation element within the heart; a memory configured to store a map of the chamber of the heart and to store a different respective default ablation parameter set for each of a plurality of different regions of the chamber; and processing circuitry, said processing circuitry comprising: segmenting the map of the room into the different regions; receiving a user input indicating the initiation of an ablation procedure; identifying an area of ​​the chamber contacted by the at least one ablation application element in response to the tracked position; automatically retrieving from the memory the respective default ablation parameter sets automatically assigned to the identified regions in response to the user input; ablation of the tissue in the identified region with the ablation probe using the automatically obtained default ablation parameter set; The ablation parameter set is an ablation mode set according to the region and according to the ablation probe.

1. A cardiac ablation system comprising:

2. The system of claim 1 , wherein the processing circuitry is configured to apply a segmented model of a cardiac chamber to the map of the chamber to result in a segmented map of the chamber.

3. the processing circuitry receiving at least one user correction to a segmentation of the segmented map; and amending the segmented map in response to the at least one received user correction.

4. the processing circuitry The system of claim 1 , further configured to segment the map into the different regions based on user markup, which is a user designation of segments of the map.

5. the processing circuitry receiving a user-defined default ablation parameter set for each of the different regions; and assigning the user-defined default ablation parameter sets to the different regions in response to a region designation for each of the received user-defined default ablation parameter sets.

6. the processing circuitry receiving user updates to the obtained default ablation parameter set to result in an updated ablation parameter set; 2. The system of claim 1, configured to perform ablation of the tissue in the identified region with the ablation probe using the updated ablation parameter set without calculating ablation parameters.

7. the processing circuitry receiving a probe type of the ablation probe; assigning, for a plurality of different probe types, a probe-specific default ablation parameter set to each of the different regions; and in response to the user input, obtaining a probe-specific default ablation parameter set assigned to the identified region based on a probe type of the received ablation probe.

8. the ablation probe includes multiple ablation application elements; the processing circuitry identifying a first region of the chamber contacted by at least a first of the multiple ablation application elements in response to the tracked position; identifying a second region of the chamber contacted by at least a second of the multiple ablation application elements in response to the tracked position; obtaining the default ablation parameter set assigned to the first region and the default ablation parameter set assigned to the second region; and applying the acquired default ablation parameter sets of the first and second regions to perform the ablation procedure in the first and second regions using the first and second of the multiple ablation application elements, respectively.

9. 2. The system of claim 1, wherein the ablation mode is selected from any one or more of: an ablation index mode, controlling ablation power according to a measured temperature, applying an alternating current to the at least one ablation application element, applying a direct current to the at least one ablation application element, laser ablation, electroporation, cryoablation, and radio frequency power ablation.

10. 1. A software product including a non-transitory computer-readable medium having stored thereon program instructions, the instructions, when read by a central processing unit (CPU), causing the CPU to: Tracking the position of at least one ablation application element of an ablation probe configured to electrically ablate tissue within a cardiac chamber of a living subject; storing a map of the chambers of the heart; storing in a memory a different respective default ablation parameter set for each of a plurality of different regions of the chamber; segmenting the map of the room into the different regions; receiving a user input indicating the initiation of an ablation procedure; identifying an area of ​​the chamber contacted by the at least one ablation application element in response to the tracked position; automatically retrieving from the memory the respective default ablation parameter sets assigned to the identified regions in response to the user input; causing the ablation probe to ablate the tissue in the identified region using the automatically obtained default ablation parameter set; The ablation parameter set is set according to the region. A software product including an ablation mode responsive to the ablation probe.

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