Methods and systems for arranging and labeling cardiac episodes based on acquired cardiac episode data are described. Cardiac episodes are algorithmically arranged based on one or more discriminating features of the episode data. A user is presented with at least one episode selected from the arrangement of cardiac episodes. The user inputs a label that characterizes the selected episode. The label is algorithmically appended to the data of the selected episode and to other episodes of the arrangement of cardiac episodes based on the discriminating features.