Advances in the use of ancillary diagnostic testing in the emergency department evaluation of chest pain.

This article discusses the advances of ancillary studies used to evaluate the emergency department patient with chest pain caused by acute myocardial infarction (AMI) or ischemia. This article examines how these studies have improved the early detection of patients with AMI, improved differentiation of acute ischemic coronary events from nonischemic causes of chest pain, more accurately stratified patients for adverse outcome, and decreased the number of patients with AMI inadvertently discharged from the emergency department. Ancillary studies discussed include nonstandard ECGs, nuclear imaging, serum markers, and emergency department observation units. Emergency department echocardiography is discussed elsewhere in the issue.