# US 2017/0281031 A1 · Mapping of atrial fibrillation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0281031 A1 - Document ID: US20170281031A1 - Status: Published application - Kind: A1 - Application number: 15/086,220 - Filed: 2016-03-31 - Published: 2017-10-05 - Earliest claimed: 2016-03-31 - Assignees: Biosense Webster (Israel) Ltd. - Applicants: Biosense Webster (Israel) Ltd. - Inventors: RICHARD P. M. HOUBEN; Meir Bar-Tal; Yaniv Ben Zriham; Roy Urman; Shmuel Auerbach - Web page: https://patentgrep.com/patent/US20170281031A1 ## CPC - A61B 5/287: Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS] - A61B 5/0036: {including treatment, e.g., using an implantable medical device, ablating, ventilating} - A61B 5/349: Detecting specific parameters of the electrocardiograph cycle - A61B 18/12: by passing a current through the tissue to be heated, e.g. high-frequency current - A61B 18/1206: {Generators therefor} - A61B 18/1492: {having a flexible, catheter-like structure, e.g. for heart ablation (A61B18/1477 takes precedence)} - A61B 5/0044: {for the heart} - A61B 5/341: Vectorcardiography [VCG] - A61B 5/4836: {Diagnosis combined with treatment in closed-loop systems or methods (A61B5/0036 takes precedence)} - A61B 5/743: {Displaying an image simultaneously with additional graphical information, e.g. symbols, charts, function plots} - A61B 2018/00351: {Heart} - A61B 2018/00636: {Sensing and controlling the application of energy} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract Electroanatomic mapping is carried out by inserting a multi-electrode probe into a heart of a living subject, recording electrograms from the electrodes concurrently at respective locations in the heart, delimiting respective activation time intervals in the electrograms, generating a map of electrical propagation waves from the activation time intervals, maximizing coherence of the waves by adjusting local activation times within the activation time intervals of the electrograms, and reporting the adjusted local activation times. ## Claims ### Claim 1 A method, comprising the steps of: inserting a probe into a heart of a living subject, the probe having a plurality of electrodes; recording electrograms from the electrodes concurrently at respective locations in the heart; delimiting respective activation time intervals in the electrograms; generating a map of electrical propagation waves from the activation time intervals, maximizing coherence of the waves by adjusting local activation times within the activation time intervals of the electrograms; and reporting the adjusted local activation times. ### Claim 2 (depends on 1) The method according to claim 1, further comprising ablating tissue in the heart to modify the waves. ### Claim 3 (depends on 1) The method according to claim 1, wherein the activation time intervals comprise first intervals delimited by a peak and a valley representing a start and an end of a slope and second intervals comprising windows about the first intervals, wherein adjusting local activation times is performed within the second intervals. ### Claim 4 (depends on 3) The method according to claim 3, wherein the windows about the first intervals are ±40 ms. ### Claim 5 (depends on 1) The method according to claim 1, wherein the local activation times at the respective locations of the electrodes are represented as fuzzy electrode membership functions (μe) that vary from 0 to 1. ### Claim 6 (depends on 1) The method according to claim 1, wherein generating the map of electrical propagation waves comprises segmenting the electrograms into a series of frames at respective times, wherein the frames are respective assignments of readings of the electrodes to a matrix of values. ### Claim 7 (depends on 6) The method according to claim 6, further comprising the steps of: assigning local activation times for the electrodes from the matrix of values; modeling at least a portion of the heart as a mesh having vertices, wherein a portion of the vertices correspond to the respective locations of the electrodes; determining conduction velocities of electrical propagation between the vertices from the frames based on the assigned local activation times; and computing the coherence of the waves using the conduction velocities. ### Claim 8 (depends on 7) The method according to claim 7, wherein maximizing coherence of the waves comprises: representing the conduction velocities as conduction velocity vectors; computing a velocity deviation vector at respective vertices from the conduction velocity vectors; and minimizing a length of the velocity deviation vector. ### Claim 9 (depends on 7) The method according to claim 7, further comprising interpolating activation times of vertices on the mesh that do not correspond to the respective locations of the electrodes. ### Claim 10 (depends on 7) The method according to claim 7, wherein activation times at the vertices of the mesh are represented as fuzzy vertex membership functions (μu) that vary between 0 and 1, the vertex membership functions at each of the vertices comprising weighted combinations of the vertex membership functions of neighboring vertices thereof. ### Claim 11 (depends on 10) The method according to claim 10, wherein maximizing coherence of the waves comprises adjusting the activation times at the vertices of the mesh to maximize an average value of the vertex membership functions in the mesh. ### Claim 12 (depends on 10) The method according to claim 10, further comprising assigning vertex membership functions to non-neighboring vertices of the mesh by extrapolation. ### Claim 13 An apparatus, comprising: a probe having a plurality of electrodes and adapted for insertion into a heart of a living subject; and a processor, which is configured to receive an electrical signal from the electrodes and to perform the steps of: recording electrograms from the electrodes concurrently at respective locations in the heart; delimiting respective activation time intervals in the electrograms; generating a map of electrical propagation waves from the activation time intervals, maximizing coherence of the waves by adjusting local activation times within the activation time intervals of the electrograms; and reporting the adjusted local activation times. ### Claim 14 (depends on 13) The apparatus according to claim 13, further comprising an ablation power generator connected to the probe for ablating tissue in the heart to modify the waves. ### Claim 15 (depends on 13) The apparatus according to claim 13, wherein the activation time intervals comprise first intervals delimited by a peak and a valley representing a start and an end of a slope and second intervals comprising windows about the first intervals, wherein adjusting local activation times is performed within the second intervals. ### Claim 16 (depends on 15) The apparatus according to claim 15, wherein the windows about the first intervals are ±40 ms. ### Claim 17 (depends on 13) The apparatus according to claim 13, wherein the local activation times at the respective locations of the electrodes are represented as fuzzy electrode membership functions (μe) that vary continuously from 0 to 1. ### Claim 18 (depends on 13) The apparatus according to claim 13, wherein generating the map of electrical propagation waves comprises segmenting the electrograms into a series of frames at respective times, wherein the frames are respective assignments of readings of the electrodes to a matrix of values. ### Claim 19 (depends on 18) The apparatus according to claim 18, further comprising the steps of: assigning local activation times for the electrodes from the matrix of values; modeling at least a portion of the heart as a mesh having vertices, wherein a portion of the vertices correspond to the respective locations of the electrodes; determining conduction velocities of electrical propagation between the vertices from the frames based on the assigned local activation times; and computing the coherence of the waves using the conduction velocities. ### Claim 20 (depends on 19) The apparatus according to claim 19, wherein maximizing coherence of the waves comprises: representing the conduction velocities as conduction velocity vectors; computing a velocity deviation vector at respective vertices from the conduction velocity vectors; and minimizing a length of the velocity deviation vector. ### Claim 21 (depends on 19) The apparatus according to claim 19, further comprising interpolating activation times of vertices on the mesh that do not correspond to the respective locations of the electrodes. ### Claim 22 (depends on 19) The apparatus according to claim 19, wherein activation times at the vertices of the mesh are represented as fuzzy vertex membership functions (μu) that vary between 0 and 1, the vertex membership functions at each of the vertices comprising weighted combinations of the vertex membership functions of neighboring vertices thereof. ### Claim 23 (depends on 22) The apparatus according to claim 22, wherein maximizing coherence of the waves comprises adjusting the activation times at the vertices of the mesh to maximize an average value of the vertex membership functions in the mesh. ### Claim 24 (depends on 22) The apparatus according to claim 22, further comprising assigning vertex membership functions to non-neighboring vertices of the mesh by extrapolation.