Noninvasive cardiac imaging.

Noninvasive cardiac imaging can be used for the diagnostic and prognostic assessment of patients with suspected or known coronary artery disease. It is central to the treatment of patients with myocardial infarction, coronary artery disease, or acute coronary syndromes with or without angina. Radionuclide cardiac imaging; echocardiography; and, increasingly, cardiac computed tomography and cardiac magnetic resonance imaging techniques play an important role in the diagnosis of coronary artery disease, which is the leading cause of mortality in adults in the United States. Contemporary imaging techniques, with either stress nuclear myocardial perfusion imaging or stress echocardiography, provide a high sensitivity and specificity in the detection and risk assessment of coronary artery disease, and have incremental value over exercise electrocardiography and clinical variables. They also are recommended for patients at intermediate to high pretest likelihood of coronary artery disease based on symptoms and risk factors. Cardiac magnetic resonance imaging and cardiac computed tomography are newly emerging modalities in the evaluation of patients with coronary artery disease. Cardiac magnetic resonance imaging is useful in the assessment of myocardial perfusion and viability, as well as function. It also is considered a first-line tool for the diagnosis of arrhythmogenic right ventricular dysplasia. Cardiac computed tomography detects and quantifies coronary calcium and evaluates the lumen and wall of the coronary artery. It is a clinical tool for the detection of subclinical coronary artery disease in select asymptomatic patients with an intermediate Framingham 10-year risk estimate of 10 to 20 percent. In addition, cardiac computed tomography is evolving as a noninvasive tool for the detection and quantification of coronary artery stenosis. Although guidelines can help with treating patients, treatment ultimately should be tailored to each person based on clinical judgment of the a priori risk of a cardiac event, symptoms, and the cardiac risk profile.