One aspect of the present invention relates to imaging a patient to determine whether he or she has suffered a myocardial infarction. According to this method, a patient is injected with a bolus having a radioactive tracer. A representative cycle is produced for both the right ventricular passage of the bolus and the left ventricular passage of the bolus based on planar coordinates over time of scintillation events of the tracer. A time activity curve based on activity in each segment of the respective representative cycles is generated. When a segment of heart muscle is damaged its contraction ceases or lags behind the normal surrounding myocardium resulting in a phase shift in the adjacent blood pool.