Imaging in Patients with Chest Pain

The accurate identification of patients at high risk for acute coronary syndromes among those seen in the emergency department with possible myocardial ischemia and nonischernic elec-trocardiograms is a problem. Two-dimensional echocardiography and myocardial perfusion imaging with 99m-technetium sestamibi can identify patients at low and high risk; however, comparative studies are lacking. The authors studied 555 patients considered at low or moderate risk for myocardial ischemia in our emergency department on the basis of the presenting history, and results of physical examination and electrocardiography. These patients underwent echocardiography and myocardial perfusion imaging within 4 hours of presentation. Endpoints included myocardial infarction, percutaneous transluminal coronary angioplasty, and positive results on stress perfusion imaging. Both imaging procedures were performed in the emergency department on 370 patients. Overall agreement between the two techniques was high (concordance, 89%) in the patients who had myocardial infarction or underwent coronary angiography. Agreement between the two techniques is high when used in patients with possible myocardial ischemia. Both techniques helped identify patients at high risk who required admission and those who could be safely discharged