Substantially-median-based determination of long-term heart rates from ecg data of wearable cardioverter defibrillator (wcd) system

A method for helping monitor a patient, the patient having worn a wearable cardioverter defibrillator (WCD) system for at least one hour during which the WCD system included a defibrillation electrode, a support structure worn by the patient so as to maintain the defibrillation electrode on a body of the patient, an energy storage module storing an electrical charge configured to be discharged via the defibrillation electrode through the patient so as to deliver a shock to the patient, an Electrocardiogram (ECG) electrode sensing an ECG signal of the patient, a WCD processor analyzing short segments of the sensed ECG signal, and a memory storing WCD system data about the sensed ECG signal, the stored WCD system data being generated from at least one hour of the sensed ECG signal, the method comprising:

• receiving the stored WCD system data;
• inputting computed raw heart rate (HR) values for respective ones of the short ECG signal segments;
• aggregating groups of the raw HR values into respective first time bins;
• deriving first HR values for respective ones of the first time bins, from at least some of the raw HR values aggregated into each first time bin;
• marking as error-prone a certain one of the first HR values for which an error condition is determined to be met;
• storing the first HR values, the stored first HR values having been thus derived from the stored WCD system data that is generated from at least one hour of the sensed ECG signal;
• displaying in a first manner the stored first HR values but not the certain first HR value, and displaying in a second manner different from the first manner the certain first HR value.

A wearable medical monitor (WMM) system, comprising:

• a plurality of Electrocardiogram (ECG) electrodes;
• a support structure configured to be worn by the patient so as to maintain the ECG electrodes on a body of the patient, the ECG electrodes thus defining two or more channels and configured to sense two or more versions of an ECG signal of the patient across the two or more channels;
• a memory;
• and
• a WMM processor configured to:
• analyze short segments of the sensed ECG signal and computing raw heart rate (HR) values for respective ones of the short ECG signal segments,
• aggregate groups of the raw HR values into respective first time bins that are arranged in a time sequence,
• discarding, from their respective first time bins, computed raw heart rate (HR) values that meet an error condition,
• derive first HR values for respective ones of the first time bins, the first HR value of a certain one of the first time bins being derived from raw HR values aggregated and remaining into the certain first time bin after the discarding, and
• then store in the memory at least some of the first HR values, the stored first HR values having been thus derived from the stored WMM system data that is generated from at least one hour of the sensed ECG signal.

A computer system for helping monitor a patient, the patient having worn a wearable medical monitor (WMM) system for at least one hour during which the WMM system included a plurality of Electrocardiogram (ECG) electrodes, a support structure worn by the patient so as to maintain the ECG electrodes on a body of the patient, the ECG electrodes thus defining two or more channels and sensing two or more versions of an ECG signal of the patient across the two or more channels, a WMM processor analyzing short segments of the sensed ECG signal, and a memory storing WMM system data about the sensed ECG signal, the stored WMM system data being generated from at least one hour of the sensed ECG signal, the computer system comprising:

• one or more computer processors distinct from the WCD processor;
• and
• a non-transitory computer-readable storage medium storing one or more programs which, when executed by the one or more computer processors, result in operations comprising:
• receiving the stored WMM system data;
• inputting computed raw heart rate (HR) values for respective ones of the short ECG signal segments;
• aggregating groups of the raw HR values into respective first time bins that are arranged in a time sequence;
• discarding, from their respective first time bins, computed raw heart rate (HR) values that meet an error condition;
• deriving first HR values for respective ones of the first time bins, the first HR value of a certain one of the first time bins being derived from raw HR values aggregated and remaining into the certain first time bin after the discarding;
• then storing at least some of the first HR values, the stored first HR values having been thus derived from the stored WMM system data that is generated from at least one hour of the sensed ECG signal.