In 2014, a total of 6 887 000 patients came to US emergency departments (EDs) because of symptoms of chest pain, representing 5% of all ED visits. While some of them have clinical evidence of acute coronary syndromes (ACS), many others have no ischemic changes on the electrocardiogram (ECG) and normal cardiac troponin levels. Uncertainty surrounds proper treatment of these low- to intermediate-risk patients.

The 2014 American College of Cardiology/American Heart Association clinical guideline for non–ST-segment elevation acute coronary syndrome gives a class IIa recommendation to noninvasive testing (exercise testing or coronary computed tomographic angiography [CCTA]) in patients with chest pain but no evidence of ischemia. In most cases, however, the results of testing are negative in this low- to intermediate-risk population, and expensive resources may be consumed with no effect on clinical outcome.

2014年，由于胸痛的症状，共有688.70万人次进入美国急诊科就诊，占所有急诊就诊次数的5％。尽管其中一些具有急性冠状动脉综合征（ACS）的临床证据，但其他许多人的心电图（ECG）和正常的心肌肌钙蛋白水平也没有缺血变化。不确定性围绕着对这些中低风险患者的正确治疗。

2014年美国心脏病学会/美国心脏协会针对非ST段抬高的急性冠状动脉综合症的临床指南对无胸痛但无证据的患者进行无创检测（运动检测或冠状动脉计算机断层血管造影[CCTA]）给予IIa类推荐缺血。但是，在大多数情况下，此低至中风险人群的检测结果是阴性的，并且可能会消耗昂贵的资源，而对临床结果没有影响。