Title: PCPs: Patient Cardiac Prototypes. Abstract: Existing deep learning methodologies within the medical domain are typically population-based and difficult to interpret. This limits their clinical utility as population-based findings may not generalize to the individual patient. To overcome these obstacles, we propose to learn patient-specific representations, entitled patient cardiac prototypes (PCPs), that efficiently summarize the cardiac state of a patient. We show that PCPs, learned in an end-to-end manner via contrastive learning, allow for the discovery of similar patients both within and across datasets, and can be exploited for dataset distillation as a compact substitute for the original dataset.