It is reasonable for patients with possible ACS who have normal serial ECGs and cardiac troponins to have a treadmill ECG200 202 (Level of Evidence: A), stress myocardial perfusion imaging,200 or stress before discharge or within 72 hours after discharge. (Level of Evidence: B) 3. In patients with possible ACS and a normal ECG, normal cardiac troponins, and no history of CAD, it is reasonable to initially perform (without serial ECGs and troponins) coronary CT angiography to assess coronary artery anatomy205 207 (Level of Evidence: A) or rest myocardial perfusion imaging with a techne- tium-99m radiopharmaceutical to exclude myocar- (Level of Evidence: B) 4. It is reasonable to give low-risk patients who are referred for outpatient testing daily aspirin, short- acting nitroglycerin, and other medication if ap- propriate (eg, beta blockers), with instructions about activity level and clinician follow-up. (Level of Evidence: C) The majority of patients presenting to the ED with chest pain do not have ACS (Figure 1), and most are at low risk for major morbidity and mortality.35 Low-risk patients are usually identi- fied by an absence of history of cardiovascular disease, normal or near-normal initial ECG, normal initial troponin, and clinical The utility of an accelerated diagnostic protocol for detecting patients with benign conditions versus those who require admission for serious disease has been established.35 At minimum, these protocols involve serial ECGs and troponin measurements, both of which can be performed in the ED, a separate chest pain unit, or a telemetry unit. 