This invention relates to the determination and/or representation of physiological information relating to a heart surface. In some aspects, a method for providing information about a patient's heart includes measuring signals from one or more electrodes at multiple positions in the heart cavity in response to electrical activity in the patient's heart cavity over multiple heart beat cycles. The method also includes generating the electroanatomical representation of a patient's heart based on the signals measured at the electrodes and information about the positions of the electrodes. The method also includes generating, by a computer, annotation information for the measured signals by applying one or more operators to the measured signals. The method also includes conveying at least some of the annotation information to a user.
