1. A system for classifying cardiac arrhythmias, the system comprising: a template waveform input to receive template data representative of a template waveform associated with a template heart beat of a known cardiac rhythm; an arrhythmic waveform input to receive arrhythmic data representative of an arrhythmic waveform associated with an arrhythmic heart beat of an arrhythmia episode; an arrhythmic heart rate input to receive an arrhythmic heart rate parameter representative of an arrhythmic heart rate associated with the arrhythmic waveform; a rate-dependent feature locator coupled to the template waveform input, the arrhythmic waveform input, and the arrhythmic heart rate parameter input, the rate-dependent feature locator adapted to determine morphological feature locations using at least the arrhythmic heart rate parameter, the morphological feature locations including template feature locations of a plurality of template morphological features on the template waveform and arrhythmic feature locations of a plurality of corresponding arrhythmic morphological features on the arrhythmic waveform; and a feature extracting module coupled to the rate-dependent feature locator, the feature extracting module adapted to extract the plurality of template morphological features from the template waveform and the plurality of corresponding arrhythmic morphological features from the arrhythmic waveform based on the morphological feature locations.