# US 12,178,582 B2 · Systems and methods for calculating patient information > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,178,582 B2 - Document ID: US12178582B2 - Status: Granted - Kind: B2 - Application number: 17/275,690 - Filed: 2019-11-08 - Published: 2022-03-31 - Granted: 2024-12-31 - Earliest claimed: 2018-11-09 - Assignees: Acutus Medical, Inc. - Applicants: Acutus Medical, Inc. - Inventors: Gunter Scharf; Christoph Scharf; Derrick Ren-yu Chou; Graydon Ernest Beatty; R. Maxwell Flaherty; J. Christopher Flaherty - Web page: https://patentgrep.com/patent/US12178582B2 ## CPC - A61B 5/0535: Impedance plethysmography (for measuring blood flow A61B5/0295) - A61B 5/0538: invasively, e.g. using a catheter - A61B 5/256: Wearable electrodes, e.g. having straps or bands - A61B 5/265: containing silver or silver chloride - A61B 5/266: containing electrolytes, conductive gels or pastes - A61B 5/282: Holders for multiple electrodes (for introduction into the body A61B5/287) - A61B 5/283: Invasive - A61B 5/287: Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS] - A61B 5/367: Electrophysiological study [EPS], e.g. electrical activation mapping or electro-anatomical mapping - A61B 5/7207: {of noise induced by motion artifacts} - A61B 5/7475: {User input or interface means, e.g. keyboard, pointing device, joystick} - A61B 5/0006: {ECG or EEG signals} - A61B 5/0033: {Features or image-related aspects of imaging apparatus, e.g. for MRI, optical tomography or impedance tomography apparatus; Arrangements of imaging apparatus in a room} - A61B 5/0036: {including treatment, e.g., using an implantable medical device, ablating, ventilating} - A61B 5/004: {adapted for image acquisition of a particular organ or body part (A61B5/0082 takes precedence; arrangements for optical scanning A61B5/0062)} - A61B 5/0044: {for the heart} - A61B 5/0048: {Detecting, measuring or recording by applying mechanical forces or stimuli (A61B5/021, A61B5/4884 and A61B9/00 take precedence)} - A61B 5/0082: {adapted for particular medical purposes} - A61B 5/0084: {for introduction into the body, e.g. by catheters (A61B5/1459 takes precedence)} - A61B 5/02: Detecting, measuring or recording for evaluating the cardiovascular system, e.g. pulse, heart rate, blood pressure or blood flow - A61B 5/024: Measuring pulse rate or heart rate - A61B 5/02427: {Details of sensor} - A61B 5/02438: {with portable devices, e.g. worn by the patient} - A61B 5/0245: by using sensing means generating electric signals, {i.e. ECG signals} - A61B 5/24: Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof - A61B 5/257: using adhesive means, e.g. adhesive pads or tapes - A61B 5/28: for electrocardiography [ECG] - A61B 5/307: specially adapted for particular uses - A61B 5/308: for electrocardiography [ECG] - A61B 5/318: Heart-related electrical modalities, e.g. electrocardiography [ECG] - A61B 5/346: Analysis of electrocardiograms - A61B 5/6802: {Sensor mounted on worn items} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract Provided herein are systems and methods for calculating patient information. The method includes determining a transfer matrix, recording electric potentials via a first set of recording electrodes located at a first set of recording locations to create a first set of recorded signals, and calculating patient information for a set of target locations by applying the transfer matrix to the first set of recorded signals. The transfer matrix is a characterization of electrical properties of tissue between the first set of recording locations and the set of target locations. ## Claims ### Claim 1 A patient information processing system, comprising: a recording assembly configured to record electric potentials via a first set of recording electrodes located at a first set of recording locations on and/or within a patient to create a first set of recorded signals; a processing unit configured to calculate patient information for a set of target locations within the patient by applying a transfer matrix to the first set of recorded signals, wherein the transfer matrix comprises a characterization of electrical properties of tissue between the first set of recording locations and the set of target locations, wherein the recording assembly is further configured to record voltages of the patient at a second set of recording locations and the processing unit is further configured to determine electrical information at the first set of recording locations, wherein the calculated patient information is based on the output of an inverse solution, and the transfer matrix is applied to improve the quality of the calculated patient information, and wherein the system is configured to apply the transfer matrix to the first set of recorded signals by applying a nonlinear geometric function of the transfer matrix to the first set of recorded signals. ### Claim 2 (depends on 1) The system according to claim 1, wherein the transfer matrix accounts for spatial anisotropy and/or temporal anisotropy. ### Claim 3 (depends on 1) The system according to claim 1, wherein the calculated patient information comprises information selected from the group consisting of: electrical information; voltage information; surface charge information; tissue charge information; dipole density information; tissue density information; electrographic flow information; impedance information; phase information; and combinations thereof. ### Claim 4 (depends on 1) The according to claim 1, wherein the calculated patient information comprises tissue density information. ### Claim 5 (depends on 4) The system according to claim 4, wherein the tissue density information comprises information related to changes in tissue density over time. ### Claim 6 (depends on 5) The system according to claim 5, wherein the change in tissue density over time comprises changes caused by ablation of the tissue. ### Claim 7 (depends on 1) The system according to claim 1, wherein the transfer matrix comprises a characterization of electrical properties of tissue between the first set of recording locations and the set of target locations. ### Claim 8 (depends on 1) The system according to claim 1, wherein: the transfer matrix is modified over time; and/or the transfer matrix is modified based on at least one varying patient parameter, and/or the transfer matrix is modified to compensate for respiration of the patient, and/or the transfer matrix is modified to compensate for cardiac motion of the patient. ### Claim 9 (depends on 8) The system according to claim 8, wherein the system is further configured to monitor the at least one varying patient parameter. ### Claim 10 (depends on 9) The system according to claim 9, wherein: the monitoring comprises continuous monitoring of the at least one varying patient parameter; and/or the transfer matrix is modified continuously. ### Claim 11 (depends on 9) The system according to claim 9, wherein: the monitoring comprises intermittent monitoring of the at least one varying patient parameter; and/or the transfer matrix is modified intermittently. ### Claim 12 (depends on 1) The system according to claim 1, wherein the applying of the transfer matrix to the first set of recorded signals comprises the processing unit applying a linear geometric function of the transfer matrix to the first set of recorded signals. ### Claim 13 (depends on 1) The system according to claim 1, wherein the system is configured to gather patient physiologic data, and wherein the patient physiologic data comprises data selected from the group consisting of: physiologic cycle data; cardiac data; respiration data; patient medication data; skin impedance data; perspiration data; thoracic and/or abdominal cavity dimensional data; water weight data; hematocrit level data; wall thickness data; cardiac wall thickness data; and combinations thereof. ### Claim 14 (depends on 1) The system according to claim 1, wherein the system is further configured to perform a device localization procedure to determine device location information. ### Claim 15 (depends on 1) The system according to claim 1, further comprising: a signal generator configured to emit a set of drive signals via a set of drive electrodes located at a set of drive locations, wherein the recording assembly is configured to record the emitted drive signals via a second set of recording electrodes located at a second set of recording locations to create a second set of recorded signals, and wherein the processing unit is configured to determine the transfer matrix by comparing the second set of recorded signals to the emitted set of drive signals. ### Claim 16 (depends on 15) The system according to claim 15, wherein the transfer matrix is determined using the magnitude and/or phase of the second set of recorded signals. ### Claim 17 (depends on 16) The system according to claim 16, wherein the transfer matrix comprises a numerical scale factor based on a comparison of the magnitude and/or phase of the second set of recorded signals to the magnitude and/or phase of the set of drive signals. ### Claim 18 (depends on 15) The system according to claim 15, wherein the emitting of the set of drive signals and the recording of the emitted drive signals occur over at least one physiologic cycle of the patient. ### Claim 19 (depends on 18) The system according to claim 18, wherein the physiologic cycle comprises a cycle selected from the group consisting of: a cardiac cycle; a respiratory cycle; a pressure cycle; and combinations thereof. ### Claim 20 (depends on 15) The system according to claim 15, wherein the determining of the transfer matrix comprises calculating and/or selecting a standardized transfer matrix. ### Claim 21 (depends on 20) The system according to claim 20, wherein the standardized transfer matrix is selected based on a patient parameter. ### Claim 22 A patient information processing system, comprising: a recording assembly configured to record electric potentials via a first set of recording electrodes located at a first set of recording locations on and/or within a patient to create a first set of recorded signals; a processing unit configured to calculate patient information for a set of target locations within the patient by applying a transfer matrix to the first set of recorded signals, wherein the transfer matrix comprises a characterization of electrical properties of tissue between the first set of recording locations and the set of target locations, wherein the recording assembly is further configured to record voltages of the patient at a second set of recording locations and the processing unit is further configured to determine electrical information at the first set of recording locations, and wherein the calculated patient information is based on the output of an inverse solution, and the transfer matrix is applied to improve the quality of the calculated patient information; and a signal generator configured to emit a set of drive signals via a set of drive electrodes located at a set of drive locations, wherein the recording assembly is configured to record the emitted drive signals via a second set of recording electrodes located at a second set of recording locations to create a second set of recorded signals, and wherein the processing unit is configured to determine the transfer matrix by comparing the second set of recorded signals to the emitted set of drive signals, and wherein the drive signals comprise: a first drive signal from a first drive electrode at a first frequency; and a second drive signal from a second drive electrode at a second frequency, wherein the first frequency and the second frequency are different. ### Claim 23 (depends on 22) The system according to claim 22, wherein the first drive signal and the second drive signal are delivered simultaneously. ### Claim 24 A patient information processing system, comprising: a recording assembly configured to record electric potentials via a first set of recording electrodes located at a first set of recording locations on and/or within a patient to create a first set of recorded signals; a processing unit configured to calculate patient information for a set of target locations within the patient by applying a transfer matrix to the first set of recorded signals, wherein the transfer matrix comprises a characterization of electrical properties of tissue between the first set of recording locations and the set of target locations, wherein the recording assembly is further configured to record voltages of the patient at a second set of recording locations and the processing unit is further configured to determine electrical information at the first set of recording locations, and wherein the calculated patient information is based on the output of an inverse solution, and the transfer matrix is applied to improve the quality of the calculated patient information; and a signal generator configured to emit a set of drive signals via a set of drive electrodes located at a set of drive locations, wherein the recording assembly is configured to record the emitted drive signals via a second set of recording electrodes located at a second set of recording locations to create a second set of recorded signals, wherein the processing unit is configured to determine the transfer matrix by comparing the second set of recorded signals to the emitted set of drive signals, and wherein the drive signals comprise: a first drive signal from a first drive electrode at a first frequency; and a second drive signal from a second drive electrode at a second frequency, wherein the first frequency and the second frequency are delivered sequentially. ### Claim 25 (depends on 24) The system according to claim 24, wherein the first frequency and the second frequency are the same frequency. ### Claim 26 A patient information processing system, comprising: a recording assembly configured to record electric potentials via a first set of recording electrodes located at a first set of recording locations on and/or within a patient to create a first set of recorded signals; a processing unit configured to calculate patient information for a set of target locations within the patient by applying a transfer matrix to the first set of recorded signals, wherein the transfer matrix comprises a characterization of electrical properties of tissue between the first set of recording locations and the set of target locations, wherein the recording assembly is further configured to record voltages of the patient at a second set of recording locations and the processing unit is further configured to determine electrical information at the first set of recording locations, and wherein the calculated patient information is based on the output of an inverse solution, and the transfer matrix is applied to improve the quality of the calculated patient information; and a signal generator configured to emit a set of drive signals via a set of drive electrodes located at a set of drive locations, wherein the recording assembly is further configured to record the emitted drive signals via a second set of recording electrodes located at a second set of recording locations to create a second set of recorded signals, wherein the processing unit is configured to determine the transfer matrix by comparing the second set of recorded signals to the emitted set of drive signals, wherein the determining of the transfer matrix comprises calculating and/or selecting a standardized transfer matrix based on a patient parameter, and wherein the patient parameter comprises a parameter selected from the group consisting of: gender; weight; height; body or body portion size; body mass index (BMI); thoracic cavity circumference; location of the esophagus; size of an atrium; filling of an atrial volume; atrial pressure; fat to water ratio; air to water to fat ratio; bone location; medications being taken; level of medication; electrolyte level; pH; pO2; pCO2; water weight; and combinations thereof.