Wearable cardioverter defibrillator (WCD) segment based episode opening and confirmation periods

A wearable cardioverter defibrillator (WCD), comprising:

• a plurality of electrocardiogram (ECG) electrodes adapted to contact a patient's skin while the patient is wearing the WCD;
• a high voltage subsystem to provide a defibrillation voltage to the patient through a plurality of defibrillator electrodes in response to a shock signal;
• and
• one or more processors to receive ECG data via the plurality of ECG electrodes, wherein the one or more processors are configured to:
• analyze multiple segments of the ECG data, wherein a segment of the ECG data comprises a portion of the ECG data,
• determine whether individual segments in a string of consecutive segments of the ECG data independently meet a shock criterion,
• in the event a predetermined number of segments in the string of consecutive segments of the ECG data meet the shock criterion, open an episode,
• determine whether an additional number of segments of the ECG data beyond the predetermined number of segments meets one or more confirmation criteria,
• in the event the additional number of segments of the ECG data meets the one or more confirmation criteria, confirm a shockable rhythm in the episode and initiate a patient alert sequence responsive to confirmation of a shockable rhythm, and
• provide the shock signal to the high voltage subsystem responsive to completion of the patient alert sequence and otherwise not providing the shock signal responsive to a patient responding to the patient alert sequence.