Electron beam computed tomography is a noninvasive imaging tool for diagnosing heart disease. The method offers new insights into coronary heart disease, because the quantification of coronary artery calcification provides a fast, low-risk and cost efficent estimation of coronary risk with greater prognostic power than traditional risk estimates. With intravenous administration of an x-ray contrast agent, EBCT can detect coronary artery stenoses more accurately than other noninvasive methods. The quanification of myocardial blood flow by EBCT represents a realistic alternative to other methods of assessing myocardial perfusion. High temporal resolution allows for detailed analysis of cardiac dynamics. Other applications include the work-up of cardiac masses, pericardial disease, and investigations of the great vessels.As a dedicated cardiac imaging tool, EBCT provides new insights into cardiac physiology and disease, and offers a quantitative approach to many diagnostic problems. Limited availability, radiation exposure, and the need for a iodinated contrast agent still make EBCT an accessory modality at this time.