# US 9,750,424 B2 · Computer-aided localization of site of origin of cardiac activation with discriminator leads > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,750,424 B2 - Document ID: US9750424B2 - Status: Granted - Kind: B2 - Application number: 14/763,102 - Filed: 2014-01-24 - Published: 2015-12-24 - Granted: 2017-09-05 - Earliest claimed: 2013-01-24 - Assignees: Dalhousie University - Applicants: Dalhousie University - Inventors: John Lewis Sapp, Jr.; Bohumil Milan Horacek - Web page: https://patentgrep.com/patent/US9750424B2 ## CPC - A61B 5/35: by template matching - A61B 5/061: {Determining position of a probe within the body employing means separate from the probe, e.g. sensing internal probe position employing impedance electrodes on the surface of the body (A61B1/00158 takes precedence)} - A61B 5/28: for electrocardiography [ECG] - A61B 5/282: Holders for multiple electrodes (for introduction into the body A61B5/287) - A61B 5/339: Displays specially adapted therefor - A61B 5/346: Analysis of electrocardiograms - A61B 5/361: Detecting fibrillation - A61B 5/363: Detecting tachycardia or bradycardia - A61B 5/366: Detecting abnormal QRS complex, e.g. widening - A61B 5/367: Electrophysiological study [EPS], e.g. electrical activation mapping or electro-anatomical mapping - A61B 5/7246: {using correlation, e.g. template matching or determination of similarity} - A61B 5/7267: {involving training the classification device} - G16H 50/70: for mining of medical data, e.g. analysing previous cases of other patients - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - G16H: HEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA ## Abstract A method for quantifying, during pacemapping, a comparison of a BSPM of interest to a pace site BSPM. The method may include receiving at a computing device a plurality of ECG signals from an acquisition system. The pace site BSPM may be calculated using the plurality of ECG signals. The BSPM of interest may be compared to the pace site BSPM, by: retrieving the BSPM of interest from memory accessible by the computing device; and, calculating one or more comparison metrics for the BSPM of interest as compared to the pace site BSPM. An indication of similarity between the BSPM of interest and the pace site BSPM based on the comparison metric calculated may be displayed on a user interface in communication with the computing device. ## Claims ### Claim 1 A method for localizing an activation site of origin to a segment of the heart comprising: obtaining a body-surface potential map (BSPM) of interest based on a plurality of simultaneously recorded electrocardiographic (ECG) signals from a first plurality of at least three leads; calculating an integral of the signal recorded from a second plurality of leads selected from the first plurality of leads wherein the second plurality of leads comprises between two leads and one less than the first plurality of leads and identifying a condition of the integral as positive or negative for each of the second plurality of leads; comparing the identified condition of each of the second plurality of leads with a condition of a plurality of pre-determined sets of BSPM templates, each set comprising one BSPM template for each pre-defined segment of the heart, to identify a selected set of BSPM templates having matching conditions; comparing the body surface potential map of interest to each BSPM template of the selected set of BSPM templates, wherein comparing comprises, for each BSPM template of the set of BSPM templates: retrieving a BSPM template from memory from the selected set of BSPM templates; and calculating one or more comparison metrics for the BSPM template retrieved as compared to the BSPM of interest, wherein each of the BSPM templates was generated by averaging BSPMs of all pacing sites within the associated segment of the heart from a collection of BSPMs stored in memory; and identifying the BSPM template that most closely resembles the BSPM of interest using the one or more comparison metrics calculated in order to identify the segment of the heart in which the activation site of origin is likely to be located. ### Claim 2 (depends on 1) The method of claim 1 wherein each of the BSPM templates of the set of BSPM templates represents a pre-determined number of ECG signals. ### Claim 3 (depends on 2) The method of claim 2 wherein the BSPMs of interest were calculated from a different number of ECG signals than the pre-determined number. ### Claim 4 (depends on 3) The method of claim 3 wherein calculation of the BSPM of interest comprises interpolating between the different number of ECG signals by application of either general or patient-specific coefficients pre-derived from a collection of BSPMs each representing the pre-determined number of ECG signals. ### Claim 5 (depends on 1) The method of claim 1 wherein the second plurality of leads comprises leads I and a VF of a 12-lead ECG. ### Claim 6 (depends on 1) The method of claim 1 wherein the second plurality of leads comprises leads II and VF of a 12-lead ECG. ### Claim 7 (depends on 4) The method of claim 4 wherein pre-deriving said coefficients comprises stimulating a plurality of known endocardial sites in order to produce tachycardia while capturing data representative of the tachycardia using a plurality of leads and subsequently applying a least-squares regression against a location of each of the known endocardial sites and the captured data. ### Claim 8 (depends on 7) The method of claim 7 wherein the plurality of known endocardial sites are on a heart of one patient. ### Claim 9 (depends on 7) The method of claim 7 wherein the plurality of known endocardial sites are on a plurality of different hearts. ### Claim 10 A method for localizing an activation site of origin to an area of the heart comprising: retrieving a plurality of general coefficient parameters relating a physical location of an activation site to integrals of ECG signals obtained by i) obtaining a plurality of simultaneously recorded electrocardiographic (ECG) signals from a plurality of leads, from each of a plurality of patients; ii) calculating an integral of the signal recorded from two of the plurality of leads; iii) obtaining the location of the activation site for each of the plurality of patients; and iv) applying a linear regression with intercept to the integrals and to the location of the pacing site to obtain the plurality of general coefficient parameters; obtaining a plurality of simultaneously recorded electrocardiographic (ECG) signals of interest from the plurality of leads used to obtain the general coefficient parameters, from a patient; calculating an integral of the ECG signal recorded from each of the plurality of leads for the patient; applying the general coefficient parameters to the integrals for the patient to obtain an estimated activation site; and displaying the location of the estimated activation site on a model of a heart.