Wearable ambulatory medical device with multiple sensing electrodes

An arrhythmia monitoring and treatment device comprising:

• a garment configured to be worn about a torso of a patient;
• a plurality of ECG sensing electrodes configured to be disposed in the garment, the plurality of ECG sensing electrodes comprising a plurality of pairs of ECG sensing electrodes configured to provide a plurality of ECG signals, each of the plurality of ECG signals corresponding to one of the plurality of pairs of ECG sensing electrodes;
• a signal acquisition circuit configured to be disposed in the garment, the signal acquisition circuit being configured to be electrically coupled to the plurality of ECG sensing electrodes and configured to sense the plurality of ECG signals;
• a plurality of therapy electrodes configured to deliver an electrical shock to the heart of the patient, the plurality of therapy electrodes in communication with a therapy delivery interface;
• a processor in communication with the signal acquisition circuit and the therapy delivery interface, the processor being configured to
• execute a selection process comprising
• identifying a quality of each of the plurality of ECG signals,
• ranking the plurality of ECG signals relative to a remainder of the plurality of ECG signals based on the identified quality of each of the plurality of ECG signals, and
• selecting at least two ECG signals to monitor, the at least two ECG signals selected having highest quality among the plurality of ECG signals based on the ranking;
• re-execute the selection process of at least two ECG signals following an event including at least one of the garment shifting on the torso, the garment being repositioned on the torso, and the garment being removed and returned to the torso of the patient;
• monitor the selected at least two ECG signals for a cardiac arrhythmia;
• and
• deliver the electrical shock to the heart of the patient via the therapy delivery interface in response to detection of the cardiac arrhythmia.