Cardiac conduction system engagement

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.

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.

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.