# US 12,758,781 B2 · Cardiac conduction system engagement > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,758,781 B2 - Document ID: US12758781B2 - Status: Granted - Kind: B2 - Application number: 17/193,794 - Filed: 2021-03-05 - Published: 2021-10-07 - Granted: 2026-10-13 - Earliest claimed: 2020-04-03 - Assignees: Medtronic, Inc. - Applicants: Medtronic, Inc. - Inventors: Subham Ghosh - Web page: https://patentgrep.com/patent/US12758781B2 ## CPC - A61N 1/3625: {External stimulators} - A61B 5/349: Detecting specific parameters of the electrocardiograph cycle - A61N 1/0404: {for external use (A61N1/06 takes precedence)} - A61N 1/36017: {with leads or electrodes penetrating the skin} - A61N 1/36031: {using physiological parameters for adjustment} - A61N 1/3702: {Physiological parameters (A61N1/365 takes precedence; evoked response A61N1/371)} - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract Systems and methods are described herein for determining whether a patient's cardiac conduction system or portions thereof are engaged by cardiac conduction system pacing therapy. One or more local metrics of electrical heterogeneity information may be generated based on surrogate cardiac electrical measured using a plurality of local external electrodes, which may be used to determine whether the patient's cardiac conduction system is engaged. ## Claims ### Claim 1 A system to determine left bundle branch engagement by an implantable medical device delivering cardiac conduction system pacing therapy, the system comprising: an electrode apparatus comprising a plurality of external electrodes to be disposed proximate a patient's skin, wherein the plurality of external electrodes comprise a plurality of left external electrodes adapted to be positioned to the left side of the patient's torso; and a computing apparatus comprising processing circuitry, the computing apparatus operably coupled to the electrode apparatus and configured to: measure surrogate cardiac electrical activation times using the plurality external electrodes of the electrode apparatus during delivery of the cardiac conduction system pacing therapy by the implantable medical device, wherein the surrogate cardiac electrical activation times are representative of depolarization of cardiac tissue that propagates through the torso of the patient, generate electrical heterogeneity information (EHI) based on the measured surrogate cardiac electrical activation times during delivery of the cardiac conduction system pacing therapy by the implantable medical device, wherein the EHI comprises a left-sided metric of dispersion based on the surrogate cardiac electrical activation times measured using the plurality of left external electrodes, determine whether a left bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device based on the left-sided metric of dispersion, and adjusting one or more paced settings of the cardiac conduction system pacing therapy for delivery by the implantable medical device when the left bundle branch of the cardiac conduction system is not determined to be engaged. ### Claim 2 (depends on 1) The system of claim 1, wherein the left-sided metric of dispersion comprises a left-sided standard deviation of surrogate cardiac electrical activation times measured using the plurality of left external electrodes. ### Claim 3 (depends on 2) The system of claim 2, wherein determining whether a left bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device based on the left-sided metric of dispersion comprises comparing the left-sided standard deviation to a local dispersion threshold value. ### Claim 4 (depends on 3) The system of claim 3, wherein the local dispersion threshold value is less than or equal to 25 milliseconds. ### Claim 5 (depends on 1) The system of claim 1, wherein the EHI further comprises a global metric of dispersion of all activation times based on the surrogate cardiac electrical activation times measured using all of the plurality of external electrodes, wherein determining whether a left bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device is also based on the global metric of dispersion of all activation times. ### Claim 6 (depends on 1) The system of claim 1, wherein the one or more paced settings comprise at least one of a voltage, a pulse width, timing of a V-pacing relative to intrinsic or paced atrial timing, pacing rate, a location of at least one implantable electrode, angle of insertion through the atrioventricular (AV) groove, a pacing polarity, a pacing vector, and a number of pacing electrodes used. ### Claim 7 (depends on 1) The system of claim 1, wherein measuring surrogate cardiac electrical activation times using the plurality external electrodes of the electrode apparatus during the delivery of cardiac conduction system pacing therapy comprises measuring surrogate cardiac electrical activation times during delivery of the cardiac conduction system pacing therapy at a plurality of different paced settings, wherein generating EHI based on the measured surrogate cardiac electrical activation times during delivery of the cardiac conduction system pacing therapy comprises generating EHI for each different paced settings of the plurality of different paced settings, and wherein determining whether a left bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy based on the left-sided metric of dispersion comprises determining whether a left bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy based on the left-sided metric of dispersion for each different paced settings of the plurality of different paced settings. ### Claim 8 (depends on 1) The system of claim 1, wherein the cardiac conduction system pacing therapy for delivery by the implantable medical device comprises ventricle from atrium (VfA) pacing therapy, wherein the VfA pacing therapy is for delivery using a tissue-piercing electrode implantable from the triangle of Koch region of the right atrium through the right atrial endocardium and central fibrous body. ### Claim 9 (depends on 1) The system of claim 1, wherein the cardiac conduction system pacing therapy for delivery by the implantable medical device comprises one or more of His bundle pacing therapy, left bundle branch area pacing, and intraseptal left ventricular endocardial pacing. ### Claim 10 A method of determining left bundle branch engagement by an implantable medical device delivering cardiac conduction system pacing therapy, the method comprising: measuring surrogate cardiac electrical activation times using a plurality external electrodes disposed proximate a patient's skin during delivery of the cardiac conduction system pacing therapy by the implantable medical device, wherein the plurality of external electrodes comprise a plurality of left external electrodes adapted to be positioned to the left side of the patient's torso, wherein the surrogate cardiac electrical activation times are representative of depolarization of cardiac tissue that propagates through the torso of the patient; generating electrical heterogeneity information (EHI) based on the measured surrogate cardiac electrical activation times during delivery of the cardiac conduction system pacing therapy by the implantable medical device, wherein the EHI comprises a left-sided metric of dispersion based on the surrogate cardiac electrical activation times measured using the plurality of left external electrodes; determining whether a left bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device based on the left-sided metric of dispersion; and adjusting one or more paced settings of the cardiac conduction system pacing therapy for delivery by the implantable medical device when the left bundle branch of the cardiac conduction system is not determined to be engaged. ### Claim 11 (depends on 10) The method of claim 10, wherein the left-sided metric of dispersion comprises a left-sided standard deviation of surrogate cardiac electrical activation times measured using the plurality of left external electrodes. ### Claim 12 (depends on 11) The method of claim 11, wherein determining whether a left bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device based on the left-sided metric of dispersion comprises comparing the left-sided standard deviation to a local dispersion threshold value. ### Claim 13 (depends on 12) The method of claim 12, wherein the local dispersion threshold value is less than or equal to 25 milliseconds. ### Claim 14 (depends on 10) The method of claim 10, wherein the EHI further comprises a global metric of dispersion of all activation times based on the surrogate cardiac electrical activation times measured using all of the plurality of external electrodes, wherein determining whether a left bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device is also based on the global metric of dispersion of all activation times. ### Claim 15 (depends on 10) The method of claim 10, wherein the one or more paced settings comprise at least one of a voltage, a pulse width, timing of a V-pacing relative to intrinsic or paced atrial timing, pacing rate, a location of at least one implantable electrode, angle of insertion through the atrioventricular (AV) groove, a pacing polarity, a pacing vector, and a number of pacing electrodes used. ### Claim 16 (depends on 10) The method of claim 10, wherein measuring surrogate cardiac electrical activation times using the plurality external electrodes during delivery of cardiac conduction system pacing therapy for delivery by the implantable medical device comprises measuring surrogate cardiac electrical activation times during delivery of the cardiac conduction system pacing therapy at a plurality of different paced settings, wherein generating EHI based on the measured surrogate cardiac electrical activation times during delivery of the cardiac conduction system pacing therapy comprises generating EHI for each different paced settings of the plurality of different paced settings, and wherein determining whether a left bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device based on the left-sided metric of dispersion comprises determining whether a left bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy based on the left-sided metric of dispersion for each different paced settings of the plurality of different paced settings. ### Claim 17 (depends on 10) The method of claim 10, wherein the cardiac conduction system pacing therapy for delivery by the implantable medical device comprises ventricle from atrium (VfA) pacing therapy, wherein the VfA pacing therapy is for delivery using a tissue-piercing electrode implantable from the triangle of Koch region of the right atrium through the right atrial endocardium and central fibrous body. ### Claim 18 (depends on 10) The method of claim 10, wherein the cardiac conduction system pacing therapy for delivery by the implantable medical device comprises one or more of His bundle pacing therapy, left bundle branch area pacing, and intraseptal left ventricular endocardial pacing. ### Claim 19 A system to determine right bundle branch engagement by an implantable medical device delivering cardiac conduction system pacing therapy, the system comprising: an electrode apparatus comprising a plurality of external electrodes to be disposed proximate a patient's skin, wherein the plurality of external electrodes comprise a plurality of right external electrodes adapted to be positioned to the right side of the patient's torso; and a computing apparatus comprising processing circuitry, the computing apparatus operably coupled to the electrode apparatus and configured to: measure surrogate cardiac electrical activation times using the plurality external electrodes of the electrode apparatus during delivery of the cardiac conduction system pacing therapy, wherein the surrogate cardiac electrical activation times are representative of depolarization of cardiac tissue that propagates through the torso of the patient, generate electrical heterogeneity information (EHI) based on the measured surrogate cardiac electrical activation times during delivery of the cardiac conduction system pacing therapy, wherein the EHI comprises a right-sided metric of dispersion based on the surrogate cardiac electrical activation times measured using the plurality of right external electrodes, determine whether a right bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device based on the right-sided metric of dispersion, and adjust one or more paced settings of the cardiac conduction system pacing therapy for delivery by the implantable medical device when the right bundle branch of the cardiac conduction system is not determined to be engaged. ### Claim 20 (depends on 19) The system of claim 19, wherein the right-sided metric of dispersion comprises a right-sided standard deviation of surrogate cardiac electrical activation times measured using the plurality of right external electrodes. ### Claim 21 (depends on 20) The system of claim 20, wherein determining whether a right bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device based on the right-sided metric of dispersion comprises comparing the right-sided standard deviation to a local dispersion threshold value. ### Claim 22 (depends on 21) The system of claim 21, wherein the local dispersion threshold value is less than or equal to 25 milliseconds. ### Claim 23 (depends on 19) The system of claim 19, wherein the EHI further comprises a global metric of dispersion of all activation times based on the surrogate cardiac electrical activation times measured using all of the plurality of external electrodes, wherein determining whether a right bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device is also based on the global metric of dispersion of all activation times. ### Claim 24 (depends on 19) The system of claim 19, wherein the one or more paced settings comprise at least one of a voltage, a pulse width, timing of a V-pacing relative to intrinsic or paced atrial timing, pacing rate, a location of at least one implantable electrode, an angle of insertion through the atrioventricular (AV) groove, a pacing polarity, a pacing vector, and a number of pacing electrodes used. ### Claim 25 (depends on 19) The system of claim 19, wherein measuring surrogate cardiac electrical activation times using the plurality external electrodes of the electrode apparatus during delivery of cardiac conduction system pacing therapy comprises measuring surrogate cardiac electrical activation times during delivery of cardiac conduction system pacing therapy at a plurality of different paced settings, wherein generating EHI based on the measured surrogate cardiac electrical activation times during delivery of the cardiac conduction system pacing therapy comprises generating EHI for each different paced settings of the plurality of different paced settings, and wherein determining whether a right bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device based on the right-sided metric of dispersion comprises determining whether a right bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy based on the right-sided metric of dispersion for each different paced settings of the plurality of different paced settings. ### Claim 26 (depends on 19) The system of claim 19, wherein the cardiac conduction system pacing therapy for delivery by the implantable medical device comprises ventricle from atrium (VfA) pacing therapy, wherein the VfA pacing therapy is for delivery using a tissue-piercing electrode implantable from the triangle of Koch region of the right atrium through the right atrial endocardium and central fibrous body. ### Claim 27 (depends on 19) The system of claim 19, wherein the cardiac conduction system pacing therapy for delivery by the implantable medical device comprises one or more of His bundle pacing therapy and right bundle branch area pacing. ### Claim 28 A method of determining right bundle branch engagement by an implantable medical device delivering cardiac conduction system pacing therapy, the method comprising: measuring surrogate cardiac electrical activation times using a plurality external electrodes disposed proximate a patient's skin during delivery of the cardiac conduction system pacing therapy by the implantable medical device, wherein the plurality of external electrodes comprise a plurality of right external electrodes adapted to be positioned to the right side of the patient's torso, wherein the surrogate cardiac electrical activation times are representative of depolarization of cardiac tissue that propagates through the torso of the patient; generating electrical heterogeneity information (EHI) based on the measured surrogate cardiac electrical activation times during delivery of the cardiac conduction system pacing therapy, wherein the EHI comprises a right-sided metric of dispersion based on the surrogate cardiac electrical activation times measured using the plurality of right external electrodes; determining whether a right bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device based on the right-sided metric of dispersion; and adjusting one or more paced settings of the cardiac conduction system pacing therapy for delivery by the implantable medical device when the right bundle branch of the cardiac conduction system is not determined to be engaged. ### Claim 29 (depends on 28) The method of claim 28, wherein the right-sided metric of dispersion comprises a right-sided standard deviation of surrogate cardiac electrical activation times measured using the plurality of right external electrodes. ### Claim 30 (depends on 29) The method of claim 29, wherein determining whether a right bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device based on the right-sided metric of dispersion comprises comparing the right-sided standard deviation to a local dispersion threshold value. ### Claim 31 (depends on 30) The method of claim 30, wherein the local dispersion threshold value is less than or equal to 25 milliseconds. ### Claim 32 (depends on 28) The method of claim 28, wherein the EHI further comprises a global metric of dispersion of all activation times based on the surrogate cardiac electrical activation times measured using all of the plurality of external electrodes, wherein determining whether a right bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy is also based on the global metric of dispersion of all activation times. ### Claim 33 (depends on 28) The method of claim 28, wherein the one or more paced settings comprise at least one of a voltage, a pulse width, timing of a V-pacing relative to intrinsic or paced atrial timing, pacing rate, a location of at least one implantable electrode, angle of insertion through the atrioventricular (AV) groove, a pacing polarity, a pacing vector, and a number of pacing electrodes used. ### Claim 34 (depends on 28) The method of claim 28, wherein measuring surrogate cardiac electrical activation times using the plurality external electrodes during delivery of cardiac conduction system pacing therapy comprises measuring surrogate cardiac electrical activation times during delivery of the cardiac conduction system pacing therapy at a plurality of different paced settings, wherein generating EHI based on the measured surrogate cardiac electrical activation times during delivery of the cardiac conduction system pacing therapy comprises generating EHI for each different paced settings of the plurality of different paced settings, and wherein determining whether a right bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device based on the right-sided metric of dispersion comprises determining whether a right bundle branch of the cardiac conduction system is engaged by the cardiac conduction system pacing therapy for delivery by the implantable medical device based on the right-sided metric of dispersion for each different paced settings of the plurality of different paced settings. ### Claim 35 (depends on 28) The method of claim 28, wherein the cardiac conduction system pacing therapy for delivery by the implantable medical device comprises ventricle from atrium (VfA) pacing therapy, wherein the VfA pacing therapy is for delivery using a tissue-piercing electrode implantable from the triangle of Koch region of the right atrium through the right atrial endocardium and central fibrous body. ### Claim 36 (depends on 28) The method of claim 28, wherein the cardiac conduction system pacing therapy for delivery by the implantable medical device comprises one or more of His bundle pacing therapy, right bundle branch area pacing.