X-ray computed tomography (CT) was first invented in 1972 and its ability to obtain cross sectional images has proven to be a major advance in the field of medicine, garnering the Nobel Prize in medicine for Sir Godfrey Newbold Hounsfield and Allan McLeod Cormack in 1979. Since then, numerous advances have been made with the introduction of high quality scanners and new imaging protocols to enhance the quality of the images and reduce the amount of radiation. Inherent drawbacks of conventional CT imaging for cardiac imaging, such as low temporal resolution and the need for ECG gating, prompted the development of electron beam CT (EBCT). Further advances in the scanners have led to the introduction of multi detector CT (MDCT) scanners, which have increased spatial resolution and now utilize sequential imaging acquisition modes and other features to minimize radiation exposure. MDCT scanners for coronary imaging utilize a minimum of 16 slice, and now 64 320 slice scanners are widely used to get excellent, high-resolution images of the heart and the coronary arteries.