A wearable medical device is provided for monitoring a cardiac condition of a patient, where the device is releasably mounted to the patient's chest and includes at least two skin-facing electrodes forming a first one or more ECG leads for ongoing monitoring of heart functioning and at least one touch electrode for intermittently obtaining additional circuit vectors for deriving additional metrics regarding the functioning of the patient's heart. Each touch electrode is configured to form an additional lead/vector that is a larger vector and/or separated by at least 15° from a corresponding first lead/vector formed from the first one or more ECG leads in a vector cardiogram representation of the first one or more ECG leads and the additional lead/vector.