Coronary heart disease is the number 1 killer of adults in the United States, affecting 1 in 5 men and women. However, women are more likely than men to die after an acute coronary event and are less likely to receive prompt or aggressive treatment. Few studies have examined the role of emergency nurses' triage decisions in these disparities, even though nurses often determine initial patient priority and urgency status for emergency cardiac evaluation and treatment. The purpose of this prospective study was to examine if nurses' initial triage decisions could predict admission or discharge diagnoses for acute coronary syndromes (ACS). A total of 108 nurses' triage decisions made by 13 nurses were examined. There were no differences in nurses' triage decisions based on patient gender, race, or age. By multivariate analysis, chest pain, history of coronary heart disease, history of myocardial infarction, and smoking were predictive of an ACS decision. Overall, accuracy for predicting admission diagnosis was poor. Sensitivity and specificity were 57% and 59%, respectively, with a positive predictive value of 68% and a negative predictive value of 56%. It was similarly poor for predicting discharge diagnosis. Sensitivity and specificity for discharge diagnosis were 55% and 69%, respectively, with a positive predictive value of 17% and a negative predictive value of 93%. Findings indicate limitations in the ability of nurses' triage decisions to predict admission and discharge diagnoses for ACS.