Coronary artery disease is the leading cause of death in the United States and the leading cause of premature permanent disability [1]. The latest statistics from the American Heart Association indicate that in 2003, more than 1 million Americans experienced an acute coronary event, more than half a million died from coronary artery disease, and more than 12 million had a history of symptomatic coronary artery disease. Total cost in the United States to diagnose and treat coronary artery disease is nearly $115 billion annually [1].
The definitive diagnosis of coronary artery disease is made by catheter coronary angiog-raphy, an invasive and expensive procedure with associated morbidity and mortality [2]. Therefore, catheter coronary angiography is often used as second-line diagnostic test after noninvasive diagnostic procedures, such as a treadmill exercise tolerance test, that provide indirect evidence of coronary artery stenosis [3]. In the past few years, progress has been made in the development of noninvasive diagnostic alternatives to directly image the coronary arteries. The two most promising noninvasive approaches are CT and MR coronary angiography.
This review describes the state of the art in cardiac imaging with CT, with emphasis on coronary artery imaging. After a more detailed description of the two principal CT technologies used in cardiac imaging�electron beam CT and MDCT�the technical aspects of ECG-gated cardiac MDCT are described. Elements relevant to the day-today clinical practice of cardiac imaging with CT are emphasized, with focus on how and why things are done, the clinical uses of this modern technology, its current limitations, and a comparison with other imaging techniques such as catheter angiography.