Automatic shaving of anatomical maps during ablation to expose internal points of interest

Abstract

The method includes receiving or generating (i) a volumetric map of at least a portion of a cavity of a body organ including a plurality of mapping locations, and (ii) ablation locations within the cavity. The volumetric map is updated by removing a portion of the mapping locations such that the ablation locations within the cavity fall on a surface of the volumetric map. Using the updated volumetric map, a map of at least a portion of the cavity is generated including the ablation locations located on a surface of the updated volumetric map. The map is displayed to a user.

Description

[Technical field]

[0001] The present invention relates generally to electroanatomical (EA) mapping, and more particularly to automated compilation of cardiac EA maps. [Background technology]

[0002] Software-based editing tools to aid in the analysis of mapped cavities of organs have previously been proposed in the patent literature. For example, in the field of dentistry, US Patent Application Publication No. 2006 / 0286501 describes using a computer to create a plan for repositioning an orthodontic patient's teeth. The computer receives an initial digital data set representing the patient's teeth in an initial position and a final digital data set representing the teeth in a final position. The computer then uses the data sets to generate a treatment path along which the teeth move from the initial position to the final position. In some embodiments, the individual tooth model includes data representing hidden tooth surfaces, such as tooth roots, imaged by X-ray, CT scan, or MRI techniques. The tooth roots and hidden surfaces may also be extrapolated from the visible surfaces of the patient's teeth.

[0003] As another example, U.S. Patent Application Publication No. 2017 / 0325891 describes a method directed to generating a three-dimensional surface representation of an anatomical structure, such as a heart chamber. More specifically, the three-dimensional surface representation of the anatomical structure is constrained relative to one or more anchor portions that correspond to received input regarding the location of anatomical features of the anatomical structure. The resulting three-dimensional surface representation includes salient features of the anatomical structure and may therefore be useful as a visualization tool during any of a variety of different medical procedures, including, for example, cardiac ablation. Summary of the Invention [Means for solving the problem]

[0004] Embodiments of the invention described below provide a method that includes receiving or generating a volumetric map of at least a portion of a cavity of a bodily organ including a plurality of mapping locations, and a point cloud of locations within the cavity that are marked for treatment. The volumetric map is updated by removing a portion of the mapping locations such that the locations marked for treatment fall on a surface of the volumetric map. Using the updated volumetric map, a map of at least a portion of the cavity is generated that includes the locations marked for treatment. The map is displayed to a user.

[0005] In some embodiments, removing a portion of the mapping locations includes identifying one or more locations marked for treatment that fall within the interior of the volume map, and removing a portion such that the identified locations marked for treatment fall on the surface of the volume map.

[0006] In some embodiments, identifying locations marked for treatment that fall within the volume map includes determining that a vector from the locations marked for treatment to their respective projection positions on the surface points in an opposite direction to an outward normal to the surface at the projection positions.

[0007] In an embodiment, the locations marked for treatment are locations on the heart wall tissue that have been marked for ablation.

[0008] In another embodiment, generating the map includes generating an electroanatomical (EA) map of at least a portion of the wall tissue.

[0009] In some embodiments, removing a portion of the mapped locations includes projecting the locations marked for treatment to their respective locations on a surface of the volume map, and removing a portion of the volume map that includes a surface that connects the locations marked for treatment to the projected locations.

[0010] In some embodiments, removing a surface connecting the locations marked for treatment to the projected locations includes removing a surface defined as a surface between a first curve generated by interconnecting the locations marked for treatment and a second curve generated by interconnecting the projected locations.

[0011] In another embodiment, removing a portion of the volume includes defining respective distances into the surface between each location marked for treatment and a respective projected location on the surface, and defining the portion to be removed based on the distances.

[0012] In an embodiment, defining the portion of the volume map to be removed includes defining a sphere having a diameter corresponding to the distance.

[0013] In another embodiment, displaying the map to the user includes presenting one or more icons at locations marked for treatment.

[0014] According to another embodiment of the present invention, there is additionally provided a system including a memory and a processor, the memory configured to store a plurality of mapping locations acquired within a cavity of a body organ and a point cloud of locations within the cavity marked for treatment, the processor configured to (i) receive or generate a volumetric map of at least a portion of the cavity including the plurality of mapping locations, (ii) update the volumetric map by removing a portion of the mapping locations such that the locations marked for treatment fall on a surface of the volumetric map, (iii) use the updated volumetric map to generate a map of at least a portion of the cavity including the locations marked for treatment, and (iv) display the map to a user.

[0015] According to another embodiment of the present invention, there is additionally provided a method including receiving or generating (i) a volumetric map of at least a portion of a cavity of a body organ including a plurality of mapping locations, and (ii) ablation locations within the cavity. The volumetric map is updated by removing a portion of the mapping locations such that the ablation locations within the cavity fall on a surface of the volumetric map. The updated volumetric map is used to generate a map of at least a portion of the cavity including the ablation locations located on a surface of the updated volumetric map. The map is displayed to a user.

[0016] In some embodiments, receiving or generating an ablation position within the cavity includes receiving a position of the ablation catheter during the ablation procedure and obtaining an average position of the ablation catheter by averaging the received catheter positions over a given duration of the ablation procedure.

[0017] In some embodiments, removing a portion of the mapping location for each average location includes: (a) projecting the average location onto a surface to find a location on the surface that is closest to the average location; (b) defining a rotational body about an axis defined by a line connecting the average location and its closest location on the surface; and (c) removing the portion that falls inside the rotational body such that the average location falls on the surface of the volume map.

[0018] In an embodiment, the body of revolution is one of a cone and an ellipsoid.

[0019] In another embodiment, removing the portion includes forcing the average position of the catheter to fall on the surface of the volume map by generating a differentiable surface at the average position.

[0020] In yet another embodiment, receiving or generating the ablation location includes tracking the ablation catheter with a position tracking system.

[0021] In some embodiments, displaying the map to the user includes presenting an icon at each average location.

[0022] In some embodiments generating the map includes generating an electroanatomical (EA) map.

[0023] According to another embodiment of the present invention, there is additionally provided a system including a memory and a processor, the memory configured to store (i) a volumetric map of at least a portion of a cavity of a body organ including a plurality of mapping locations, and (ii) ablation locations within the cavity, the processor configured to (a) update the volumetric map by removing a portion of the mapping locations such that the ablation locations within the cavity fall on a surface of the volumetric map, (b) use the updated volumetric map to generate a map of at least a portion of the cavity including the ablation locations located on a surface of the updated volumetric map, and (c) display the map to a user. [Brief description of the drawings]

[0024] The invention will be more fully understood from consideration of the following detailed description taken in conjunction with the drawings, in which: [Figure 1] 1 is a schematic, pictorial illustration of a system for electroanatomical (EA) mapping and ablation, in accordance with an embodiment of the present invention. [Diagram 2] 1 is a volume-rendered semi-transparent EA map of the left atrium showing locations marked for ablation and their respective projected locations on the surface of the EA map, in accordance with an embodiment of the present invention. [Diagram 3] 1 is a flow chart that generally illustrates a method for exposing locations of heart chambers marked for ablation, in accordance with an embodiment of the present invention. [Figure 4A]11A-11C are volume-rendered non-transparent maps of a heart chamber showing a surface hiding icons of locations for ablation, and a re-meshed surface with icons exposed at locations marked for ablation, according to an embodiment of the present invention. [Figure 4B] 11A-11C are volume-rendered non-transparent maps of a heart chamber showing a surface hiding icons of locations for ablation, and a re-meshed surface with icons exposed at locations marked for ablation, according to an embodiment of the present invention. [Figure 5A] FIG. 13 is a schematic diagram illustrating the removal of a volume of an EA map so that the average position of the ablation catheter falls on the adjusted surface of the EA map, in accordance with an embodiment of the present invention. [Figure 5B] FIG. 13 is a schematic diagram illustrating the removal of a volume of an EA map so that the average position of the ablation catheter falls on the adjusted surface of the EA map, in accordance with an embodiment of the present invention. [Figure 6] 1 is a flow chart that generally illustrates a method for exposing a location of a heart chamber during ablation, in accordance with an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] overview Cavities of a patient's organ, such as heart chambers, also referred to below as ventricles, may be mapped (e.g., electroanatomically mapped) using a mapping catheter having one or more suitable sensors, such as electrodes attached to a distal end for mapping within the organ. Using position signals generated by the various sensors, the processor may calculate sensor locations within the organ (e.g., locations of sensing electrodes inside the heart chamber). Using the calculated locations, the processor may further derive an anatomical map of the cavity surface. In the case of a heart chamber (e.g., a ventricle), the processor may derive an electroanatomical (EA) map of the cavity surface. In some embodiments, such an EA map also graphically indicates arrhythmogenic locations on the cavity wall tissue that should be ablated for the treatment of arrhythmia.

[0026] Thus, typically, prior to a cardiac ablation procedure, the ventricles are mapped (i) to obtain a volumetric representation of the ventricular anatomy, and (ii) to obtain a point cloud of locations within the ventricles that are to be marked for ablation. At least some of the locations marked for ablation are typically located along curved lines. For example, in fast anatomical mapping (FAM) of the ventricles, acquired EA data is used to delineate point locations for ablation on the inner surface of the cavity. The physician can then ablate locations along the curved lines to block abnormal electrophysiological signals, such as in the case of isolating the pulmonary vein ostia in the left atrium.

[0027] However, erroneous catheter positions may be acquired and automatically added to the FAM-constructed cavity surface during FAM reconstruction. Examples of such undesirable data points include cavity wall positions distorted by being pushed outward by the catheter, as well as erroneous wall positions due to respiratory-induced motion.

[0028] The accumulation of such undesired positions affects the accuracy of the reconstructed EA map. To address these inaccuracies, during or after acquisition, the physician or a specialist assisting the physician may manually edit the surface generated from the acquired points to correct the errors. This manual editing typically involves erasing positions and / or removing ("shaving") entire parts from the computed surface. However, this manual editing is a time-consuming process.

[0029] Furthermore, in some cases, an erroneous catheter location may occlude or hide markings indicating wall tissue locations selected for treatment, such as cardiac wall tissue locations selected for ablation. While locations for ablation are typically marked (e.g., superimposed) on the map as icons (e.g., "visitags"), some of the icons may be invisible because they appear inside the chamber rather than on the chamber's outer surface due to the above or other mapping errors.

[0030] An embodiment of the present invention uses the underlying assumption that the mapping locations marked for treatment (e.g., ablation) are correct, and that any occlusion of such markings by other locations on the cavity wall is due to incorrect mapping of the wall tissue. Such mapping errors would cause locations marked for treatment to erroneously appear inside the chamber, which would cause icons pointing to these locations (e.g., visitag icons) to be hidden in a typical non-transparent view of a map of an organ cavity.

[0031] To overcome such errors, the processor corrects the mapping of the cavity so that the locations marked for treatment fall on the cavity wall. In an embodiment, the processor receives or generates an EA map of at least a portion of the volume of the heart chamber and a point cloud of locations marked for treatment (e.g., ablation). The processor verifies that one or more of the locations marked for treatment fall within the interior of the volume, and accordingly updates the volume by removing a portion of the mapping locations so that the locations marked for treatment fall on the surface of the volume of the ventricular map. Using the updated EA mapping data, the processor generates a map of at least a portion of the cavity, including the locations marked for treatment, and displays the map to the user.

[0032] In another embodiment, to remove a portion of the mapped locations, the processor projects the locations marked for treatment onto the modeled surface of the cavity. The processor then connects the locations marked for treatment by a first spline and the projected locations by a second spline. A "ball rolling" algorithm is then used. A "ball" with a variable radius found by connecting the locations marked for treatment and the projected locations, respectively, is "rolled" along the two splines, and anatomical locations in the chamber volume and surface are removed from the group. The chamber surface is then reconstructed using the updated data set to reveal the original locations marked for treatment (e.g., to make their icons visible in an external view of the model). In general, shapes other than balls can be used, such as ellipsoid shapes with variable width and diameter.

[0033] In an additional embodiment, the processor begins exposing locations for ablation (an operation called "shaving" the EA map) as soon as ablation begins. One purpose of this shaving is to ensure that the ablation site always corresponds to a location on the surface of the EA map (rather than accidentally falling within the blood volume of the EA map due to mapping error).

[0034] This embodiment has two essential differences with respect to the above. There is no need to wait for the 1-visitag icon to be created. 2- The shaving process can affect the ablation location as the map changes during ablation.

[0035] In this embodiment, the processor receives (or generates) an EA map of at least a portion of the ventricular volume and further receives the ablation catheter position during ablation. While performing the ablation, the processor averages the ablation catheter position over a recent predefined duration (e.g., over 5 seconds). Several criteria, such as electrode-tissue contact quality and catheter stability, can be taken into account as a filter to determine the average position within the duration.

[0036] The processor then calculates the location (e.g., point) on the surface that is closest to the average ablation catheter position found above. The processor defines a cone or ellipsoid that starts (i.e., has its head) at the average catheter position and has its axis along the line connecting the average catheter position and its projection onto the map surface (the closest point found above). The cone / ellipsoid has a predefined opening angle.

[0037] Finally, the processor removes the EA map volumes that fall inside the cone / ellipsoid constructed above and corrects the EA map surface accordingly so that the average position of the ablation catheter falls on the adjusted surface of the EA map.

[0038] By exposing hidden landmarks (e.g., icons) of locations marked for treatment, the disclosed technology may help physicians improve the quality of complex diagnostic tasks performed during diagnostic catheterization, such as marking (e.g., by visitag icons) mapped tissue locations for ablation. Another advantage of the disclosed technology is that it reduces the editing time of each portion of the EA map, for example, when done manually for this purpose.

[0039] System Description FIG. 1 is a schematic, pictorial illustration of a system 21 for electroanatomical (EA) mapping and ablation, according to an embodiment of the present invention. FIG. 1 shows a physician 27 using a Pentaray® EA mapping catheter 29 to perform EA mapping and / or electrical ablation of a heart 23 of a patient 25. The catheter 29 comprises at its distal end one or more arms 20, which may be mechanically flexible, with one or more electrodes 22 coupled to each arm. During a mapping procedure, the electrodes 22 acquire and / or inject unipolar and / or bipolar signals from and / or to tissue of the heart 23. To perform ablation, the electrodes 22 are connected (e.g., switched) to an ablation waveform generator (not shown) in a console 30.

[0040] During mapping, processor 28 in console 30 receives diagnostic signals via electrical interface 35 and uses information contained in these signals to construct EA map 40 that processor 28 stores in memory 33. During and / or after a procedure, processor 28 may display EA map 40 on display 26. User controls 32 of user interface 100 allow physician 27 to communicate with processor 28 to command editing and / or highlighting of portions of EA map 40. Controls 32 may include, for example, a trackball and control knobs, as well as a keyboard. Other elements of user interface 100 may include touch screen functionality of display 26.

[0041] During the procedure, a tracking system may be used to track the location of each of the sensing electrodes 22, thereby associating each of the signals with the location where the signal was obtained. For example, the Active Catheter Location (ACL) system from Biosense-Webster (Irvine California), described in U.S. Pat. No. 8,456,182, the disclosure of which is incorporated herein by reference, may be used. In the ACL system, a processor estimates the location of each of the electrodes based on the impedance measured between each of the sensing electrodes 22 and a number of surface electrodes 24 coupled to the skin of the patient 25. For example, three surface electrodes 24 may be coupled to the patient's chest and another three surface electrodes may be coupled to the patient's back. (For ease of illustration, only one surface electrode is shown in FIG. 1.) Current is passed between the electrodes 22 and the surface electrodes 24 inside the patient's heart 23. The processor 28 calculates the estimated location of all of the electrodes 22 within the patient's heart based on the ratio between the current amplitudes (or between the impedances indicated by these amplitudes) measured at the surface electrodes 24 and the known locations of the electrodes 24 on the patient's body. In this way, the processor can associate any given impedance signal received from the electrodes 22 with the location where the signal was obtained.

[0042] The exemplary illustration shown in FIG. 1 is selected solely for conceptual clarity. Other tracking methods may be used, such as methods based on measuring voltage signals. Other types of detection catheters, such as the Lasso® catheter (Biosense Webster), or basket catheters, may equally be used. A contact sensor may be attached to the distal end of the EA mapping catheter 29. As mentioned above, other types of electrodes, such as electrodes used for ablation, may be attached to electrodes 22 for acquiring the required position data and utilized in a similar manner. Thus, in this case, the ablation electrodes used to collect the position data are considered to be the sensing electrodes. In an optional embodiment, the processor 28 is further configured to indicate the quality of physical contact between each of the electrodes 22 and the inner surface of the ventricle during the measurement.

[0043] Other catheter types can be used for ablation and EA mapping, such as balloon catheters and basket catheters.

[0044] Processor 28 typically comprises a general-purpose computer with software programmed to perform the functions described herein. In particular, processor 28 executes the dedicated algorithms disclosed herein, including FIG. 3, that enable processor 28 to perform the disclosed steps, as described further below. The software may be downloaded to the computer in electronic form, for example over a network, or alternatively or additionally may be provided and / or stored on a non-transitory tangible medium, such as magnetic, optical, or electronic memory.

[0045] Automatic remeshing of anatomical maps of internal points of objects FIG. 2 is a volume-rendered semi-transparent EA map 200 of the left atrium showing locations marked for ablation (202) and their respective projected locations 204 on the surface of the EA map, according to an embodiment of the present invention.

[0046] 2 illustrates a map merely for clarity and brevity of presentation. The disclosed process does not necessarily require generating such an initial map. Rather, acquired data including locations is received into a processor, which applies the disclosed steps to the mapped volume.

[0047] As can be seen, the mapping locations 202 marked for ablation each follow the circumference of a pulmonary vein ostium 222. The mapping locations may define a contour (not shown) along which subsequent ablation is performed to isolate the arrhythmia.

[0048] As mentioned above, an error in the map 200 can cause the icon for location 202 to be hidden in a non-transparent view.

[0049] In one embodiment of the disclosed technology, the processor identifies only those locations 202 marked for treatment that fall within the mapped volume by determining whether the vector between each location 202 marked for treatment and its respective projected surface location 204 is opposite to the outward normal to the surface of the cavity at the projected location. The processor then projects the locations 202 onto the surface location 204 for later generating a map on which icons of the locations 202 are visible, as described below.

[0050] In another embodiment, the processor projects all points marked for treatment without attempting to identify which of their locations are interior: if a point is already on the surface, the diameter of the rolled ball, or the local volume to be removed, will be zero or negligible.

[0051] The cavity shown is the left atrium, but the description applies to cavities in other organs and to treatments other than ablation.

[0052] 3 is a flow chart that diagrammatically illustrates a method for exposing locations of a heart chamber marked for ablation, according to an embodiment of the present invention. The algorithm executes a process that, according to the embodiment presented, begins with processor 28 receiving an EA map of at least a portion of the volume of the heart chamber and a point cloud of locations marked for ablation, in a data reception step 302. At this stage, some of the locations marked for ablation may include hidden icons.

[0053] Processor 28 then projects the locations marked for ablation onto their respective locations on the surface of the ventricular map volume, at a data projection step 304 .

[0054] In a data connection step 306, processor 28 connects the locations marked for ablation by a first spline and connects each of the projected locations found in step 304 by a second spline.

[0055] Next, in a point cloud update step 308, the processor 28 generates an updated volume by automatically removing a portion of the volume, including a surface that connects the locations marked for ablation with the projected locations. For example, the processor "rolls" a ball with a variable diameter (or "rolls" the aforementioned ellipsoid) along two splines, and removes the intersection of the chamber volume with the rolled ball or ellipsoid from the chamber map volume.

[0056] In an EA map generation step 310, using the updated mapping data or chamber volume map, processor 28 generates an EA map of a portion of the heart chamber that includes visible icons marking the ablation locations, such as map 440 below.

[0057] Finally, in a map display step 312, processor 28 presents the EA map to the user.

[0058] The exemplary flow chart shown in Figure 3 has been chosen purely for purposes of conceptual clarity, for example, in alternative embodiments the cavity is of an organ other than the heart.

[0059] Anatomical map reshaping mesh 4A and 4B are volume-rendered, non-transparent EA maps 400 and 440, respectively, of a heart chamber showing a surface 405 that hides icons at ablation locations (402), and a re-meshed surface with icons (404) exposed at locations marked for ablation, in accordance with an embodiment of the present invention.

[0060] As can be seen in Fig. 4A, almost all of the icons marking locations 402 for ablation on the ostia of two pulmonary veins in the left atrium are hidden under surface 405. On the other hand, in Fig. 4B, the reconstruction surface 410 exposes the respective locations, as indicated by icons 404.

[0061] A physician can use the map 440 to perform the necessary ablation.

[0062] Shaving the anatomical map during ablation 5A and 5B are schematic diagrams showing the removal of volumes (512, 522) of the EA map so that the average position (504, 514) of the ablation catheter falls on the adjusted surface (520, 530) of the EA map in accordance with an embodiment of the present invention.

[0063] FIG. 5A shows an EA map of a portion of a ventricular volume, where the interior and exterior of the chamber volume are marked and separated by the surface 502 of the mapped volume. Additionally, the average position 504 of the ablation catheter during the last predefined time range in which the catheter was applying ablation is shown. As can be seen, the average position 504 falls inside the volume, not on the surface of the map. Such an error occurs, for example, when during mapping, the mapping catheter is pressed hard against the cavity wall, and the mapping position therein does not represent the nominal shape of the ventricle. This case is better seen in FIG. 5B, where the surface of the EP map has a bulge at surface location 516.

[0064] Also shown in FIG. 5A is the closest point 506 to the average ablation catheter position 504 on the surface of the volume. The processor defines a body of revolution (e.g., a cone 510) whose axis 508 runs along the line connecting the average catheter position 504 and its projection onto the map surface (the closest point 506 found above). The cone has a predefined opening angle. To expose the position 504, all EA map volumes 512 defined inside the cone constructed above are removed. The EA map has a resized surface 520, and the average ablation catheter position 504 falls on the resized surface 520 of the EA map.

[0065] FIG. 5B shows another case of the average position 514 of the ablation catheter while applying the ablation. As mentioned above, the average position 514 also falls within the volume. The closest point 516 on the surface of the volume, together with the position 514, defines the axis 518 of a body of revolution (e.g., a cone 511). To expose the position 514, all EA map volumes 522 defined inside the cone constructed above are removed. The EA map in FIG. 5B has a fitted surface 530, and the average position 514 of the ablation catheter falls on the fitted surface 530 of the EA map.

[0066] 5A and 5B are shown as examples, other types of revolutions may be used, such as those made by exponential curves, power law curves, etc., or combinations thereof, to cause the processor to generate a smooth fitted surface (e.g., a differentiable surface at the mean position).

[0067] 6 is a flow chart that generally illustrates a method for exposing the location of a heart chamber during ablation, according to an embodiment of the present invention. The processor begins exposing (e.g., shaving) as soon as ablation begins, without having to wait for a visitag icon to be created. Furthermore, since the map changes during ablation, the shaving process may affect the ablation location.

[0068] The algorithm executes a process that begins, in the example presented, with processor 28 receiving an EA map of at least a portion of the ventricular volume and the ablation catheter position during ablation, at data reception step 602.

[0069] While performing the ablation, the processor averages the ablation catheter positions during the last predefined time range (eg, over 5 seconds) in a catheter position averaging step 604 .

[0070] Next, the processor calculates the location on the surface that is closest to the average ablation catheter location found above in a find closest location on surface step 606.

[0071] Next, the processor defines a body of revolution (eg, a cone or an ellipsoid) as defined in Figures 5A and 5B above, in a body of revolution definition step 608.

[0072] Next, the processor removes all EA map volumes defined inside the cone / ellipsoid constructed above in an EA volume removal step 610.

[0073] In an EA map correction step 612, the processor corrects the EA map surface so that the average position of the catheter falls on the surface of the EA map.

[0074] Finally, in a map display step 614, processor 28 presents the adjusted EA map to the user.

[0075] The flow chart in Figure 6 is presented simply for clarity as an example. Further steps may include removing catheter positions deemed unstable or with poor contact with tissue. The average position may be tagged with an icon as an ablated position on the cavity wall.

[0076] The above embodiments are cited by way of example, and it will be understood that 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 subcombinations of the various features described in the above specification, as well as variations and modifications thereof not disclosed in the prior art that would occur to a person skilled in the art upon reading the foregoing description. Documents incorporated by reference into this patent application shall be considered as an integral part of this application, provided that, to the extent that any term is defined in these incorporated documents in a manner that is inconsistent with the definition expressly or implicitly made herein, only the definition in this specification shall be considered.

[0077] [Embodiment] (1) receiving or generating (i) a volumetric map of at least a portion of a cavity of a body organ, the volumetric map including a plurality of mapping locations, and (ii) ablation locations within the cavity; updating the volume map by removing a portion of the mapping location such that the ablation location within the cavity falls on a surface of the volume map; using the updated volumetric map to generate a map of at least a portion of the cavity, the map including the ablation locations located on a surface of the updated volumetric map; and displaying the map to a user. (2) The method of embodiment 1, wherein receiving or generating the ablation position within the cavity includes receiving a position of an ablation catheter during an ablation procedure and obtaining an average position of the ablation catheter by averaging the catheter positions received over a given duration of the ablation procedure. (3) removing the portion of the mapping locations for each average location; projecting said average position onto said surface to find a position on said surface that is closest to said average position; defining a body of revolution about an axis defined by a line connecting said average position and its nearest position on said surface; and removing the portion that falls inside the body of revolution such that the average position falls on a surface of the volume map. (4) The method of embodiment 3, wherein the rotating body is one of a cone and an ellipsoid. (5) The method of embodiment 3, wherein removing the portion includes fitting the average position of the catheter onto a surface of the volume map, and generating a differentiable surface at the average position.

[0078] (6) The method of embodiment 2, wherein receiving or generating the ablation position includes tracking the ablation catheter with a position tracking system. (7) The method of embodiment 2, wherein displaying the map to the user includes presenting an icon at each average location. (8) The method of embodiment 1, wherein generating the map includes generating an electroanatomical (EA) map. (9) a memory configured to store: (i) a volumetric map of at least a portion of a cavity of a body organ, the volumetric map including a plurality of mapping locations; and (ii) an ablation location within the cavity; 1. A processor comprising: updating the volume map by removing a portion of the mapping location such that the ablation location within the cavity falls on a surface of the volume map; using the updated volumetric map to generate a map of at least a portion of the cavity, the map including the ablation locations located on a surface of the updated volumetric map; and a processor configured to display the map to a user. (10) The system of embodiment 9, wherein the processor is configured to receive a position of an ablation catheter during an ablation procedure and store the ablation position by obtaining an average position of the ablation catheter by averaging the catheter positions received over a given duration of the ablation procedure.

[0079] (11) The processor, projecting said average position onto said surface to find a position on said surface that is closest to said average position; defining a solid of revolution about an axis defined by a line connecting said average position and its nearest position on said surface; by removing the portion that falls inside the body of revolution such that the average position falls on the surface of the volume map; 11. The system of claim 10, configured to remove the portion of the mapping positions for each average position. (12) The system of embodiment 11, wherein the rotating body is one of a cone and an ellipsoid. (13) The system of embodiment 11, wherein the processor is configured to fit the average position of the catheter onto a surface of the volume map by generating a differentiable surface at the average position. (14) The system of embodiment 11, wherein the processor is configured to obtain the ablation position by tracking the ablation catheter with a position tracking system. (15) The system of embodiment 10, wherein the processor is configured to display the map to the user by presenting an icon at each average location.

[0080] (16) The system of embodiment 9, wherein the processor is configured to generate the map by generating an electroanatomical (EA) map.

Claims

1. a memory configured to store (i) a volumetric map of at least a portion of a body organ cavity, the volumetric map including a plurality of mapping locations; and (ii) an ablation location within the cavity; 1. A processor comprising: updating the volume map by removing a portion of the mapping location such that the ablation location within the cavity falls on a surface of the volume map; using the updated volumetric map to generate a map of at least a portion of the cavity, the map including the ablation locations located on a surface of the updated volumetric map; and a processor configured to display the map to a user.

2. 2. The system of claim 1, wherein the processor is configured to receive a position of an ablation catheter during an ablation procedure and store the ablation position by obtaining an average position of the ablation catheter by averaging the catheter positions received over a given duration of the ablation procedure.

3. The processor, projecting said average position onto said surface to find a position on said surface that is closest to said average position; defining a solid of revolution about an axis defined by a line connecting said average position and its nearest position on said surface; by removing the portion that falls inside the body of revolution such that the average position falls on the surface of the volume map; The system of claim 2 configured to remove the portion of the mapping positions for each average position.

4. The system of claim 3 , wherein the body of revolution is one of a cone and an ellipsoid.

5. The system of claim 3 , wherein the processor is configured to fit the average position of the catheter onto a surface of the volume map by generating a differentiable surface at the average position.

6. The system of claim 3 , wherein the processor is configured to obtain the ablation location by tracking the ablation catheter with a position tracking system.

7. The system of claim 2 , wherein the processor is configured to display the map to the user by presenting an icon at each average location.

8. The system of claim 1 , wherein the processor is configured to generate the map by generating an electroanatomical (EA) map.

9. Receiving or generating (i) a volumetric map of at least a portion of a body organ cavity, the volumetric map including a plurality of mapping locations, and (ii) ablation locations within the cavity; updating the volume map by removing a portion of the mapping location such that the ablation location within the cavity falls on a surface of the volume map; using the updated volumetric map to generate a map of at least a portion of the cavity, the map including the ablation locations located on a surface of the updated volumetric map; and displaying the map to a user.

10. 10. The method of claim 9, wherein receiving or generating the ablation location within the cavity comprises receiving a location of an ablation catheter during an ablation procedure and obtaining an average location of the ablation catheter by averaging the catheter locations received over a given duration of the ablation procedure.

11. removing the portion of the mapping positions for each average position; projecting said average position onto said surface to find a position on said surface that is closest to said average position; defining a body of revolution about an axis defined by a line connecting said average position and its nearest position on said surface; and removing the portion that falls inside the body of revolution such that the average position falls on a surface of the volume map.

12. The method of claim 11 , wherein the body of revolution is one of a cone and an ellipsoid.

13. The method of claim 11 , wherein removing the portion comprises fitting the average position of the catheter onto a surface of the volume map, generating a differentiable surface at the average position.

14. The method of claim 10 , wherein receiving or generating the ablation location comprises tracking the ablation catheter with a position tracking system.

15. The method of claim 10 , wherein displaying the map to the user includes presenting an icon at each average location.

16. The method of claim 9 , wherein generating the map comprises generating an electroanatomical (EA) map.

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