Recent developments in the prognostic use of myocardial perfusion imaging

Stress myocardial perfusion imaging has become a mainstay in the noninvasive assessment of patients with known or suspected coronary artery disease for several compelling reasons. Radionuclide myocardial perfusion imaging can be performed using a variety of stressors, including exercise, pharmacologic stress (including dipyridamole, adenosine, dobutamine, and arbutamine), or a combination of exercise and pharmacologic stress. The combination of exercise and pharmacologic stress allows an assessment of the patient's exercise tolerance, to be performed while adequately stressing him or her pharmacologically. Radiopharmaceutical choice has been expanded to include not only thallium-201 but also technetium-based imaging agents such as sestamibi and tetrofosmin. The use of technetium imaging agents has recently been enhanced by the ability to assess ventricular function using gated single-photon emission computed tomography (SPECT) imaging techniques. Finally, the ability to provide prognostic information in the same patients has led to incremental clinical use.