Trials of Imaging Use in the Emergency Department for Acute Chest Pain.

Over 8 million patients seek emergency department care for acute chest pain annually in the United States alone, and <5% have an acute coronary syndrome. In the absence of overt electrocardiographic or biomarker evidence, expensive and time-consuming diagnostic strategies are frequently required. Beginning in 2000, radionuclide myocardial perfusion, stress echocardiography, cardiac magnetic resonance imaging, and coronary computed tomographic angiography have become increasingly common in evaluating these patients. This review paper focuses on randomized clinical trials that provide the evidence base for these diagnostic strategies. Novel imaging modalities combining high-sensitivity troponin with imaging or combined anatomic-physiological evaluation using fractional flow reserve by computed tomography are also discussed.