1. A system for determining cardiovascular information for a patient, the system comprising: at least one computer system configured to: receive patient-specific data regarding a geometry of at least a portion of an anatomical structure of the patient, the anatomical structure including at least a portion of a plurality of arteries and myocardial tissue connected to at least some of the plurality of arteries; create a three-dimensional model representing the anatomical structure of the patient based on the patient-specific data; divide at least a portion of the three-dimensional model representing the myocardial tissue into segments; and determine perfusion information associated with at least one of the segments based on the three-dimensional model and a physiological condition of the patient.