Diagnostic testing of the emergency department patient with chest pain.

In evaluating patients with nondiagnostic initial clinical or electrocardiogram (ECG) findings for acute cardiac ischemia, continuous 12-lead ECG monitoring increases the detection of diagnostic ECG findings, including ST-segment elevation, in patients awaiting hospital admission. Rest scanning with technitium-99m sestamibi is able to risk stratify low-moderate risk patients into lower and higher risk groups for cardiac events. Caveats include the reduced sensitivity of scanning of patients who are pain free and the need for follow-up exercise scans for patients free of perfusion defects at rest. Cardiac markers, particularly the troponins, show great promise for the detection of a larger part of the spectrum of acute coronary syndromes in the emergency department, including patients with minimal myocardial damage and higher risk for short-term death and nonfatal acute myocardial infarction. Accelerated diagnostic protocols using serial testing with cardiac markers, ECGs and then provocative testing over a 14-hour period, are feasible, safe, and cost-effective.