Investigating stable chest pain of suspected cardiac origin.

Cardiovascular disease is a leading cause of death in the United Kingdom; however, most first presentations with chest pain to primary care have a non-cardiac cause. It is important to establish which patients’ symptoms are caused by obstructive coronary artery disease, so that these patients can be optimally managed to control angina and reduce mortality. To support clinical decision making, the National Institute for Health and Care Excellence (NICE) published guidance in 2010 on the assessment of patients with chest pain of suspected cardiac origin. This advice proposed a major change in clinical practice by no longer recommending exercise ECG to investigate stable chest pain in patients without known coronary artery disease. Exercise ECG is limited by the need for an interpretable ECG, the ability of the patient to exercise adequately, and a wide variability in diagnostic accuracy compared with cardiac imaging. 6 The assessment of patients with suspected stable chest pain begins with a full history, clinical evaluation, and resting ECG. Subsequent investigation is guided by calculating the pre-test probability of coronary artery disease using age, sex, risk factors, and symptom characteristics (see table⇓ and fig 1⇓). The NICE guidelines stratify patients into three risk groups and recommend a different strategy for cardiac investigations in each group. Most patients will have symptomatic coronary artery disease diagnosed or excluded on the basis of non-invasive cardiac imaging, with invasive angiography reserved for higher risk patients being considered for revascularisation. With increasing use of cardiac computed tomography in lower risk populations, the effect of radiation dose is an important consideration, although this might be offset by fewer patients undergoing nuclear medicine studies. As newer imaging technology becomes available, radiation dose and diagnostic accuracy may continue to improve. Typical dose ranges are given below for tests that use ionising radiation and should be considered against the annual background dose of about 3 mSv.