Abstract: To analyze a human patient's heart activity over an extended period of time a portable EKG monitor is attached to the patient through electrodes and the patient maintains a diary of his activities and subjective feelings over a monitoring period. The recorded data is then used to form a graphic record consisting of a plurality of trace segments each representative of short consecutive intervals in the overall monitoring period. These records are necessarily to a very reduced scale and to allow the physician to obtain more detailed information regarding anomolous periods the graphic record is observed and various interesting segments are recorded on a substantially amplified scale. The first macroscopic and the second microscopic display segment are arranged in book form with the enlarged microscopic display segments on opposed pages from the macroscopic display segments to allow their simultaneous review and evaluation.