CTA is superior to coronary CT calcium scan in determining the risk of Major Adverse Cardiac Events (MACE).

[1] Faster CT machines, due to multidetector capabilities, have made imaging of the heart and circulatory system very practical in a number of clinical settings.

[7] However, one of the unique features of cardiac CTA is the fact that it enables the visualization of the vessel wall, in a non-invasive manner.

By comparison, a chest X-ray carries a dose of approximately 0.02-0.2 mSv[10] and natural background radiation exposure is around 2.3 mSv/year.

This can result in a significant decrease in radiation exposure, at the risk of compromising image quality if there is any arrhythmia during the acquisition.

Cardiac arrhythmias, coronary artery stents and tachycardia may result in a reduced image quality.

Dual Source CT scanners, introduced in 2005, allow higher temporal resolution by acquiring a full CT slice in only half a rotation, thus reducing motion blurring at high heart rates and potentially allowing for shorter breath-hold time.

The speed advantages of 64-slice MSCT have rapidly established it as the minimum standard for newly installed CT scanners intended for cardiac scanning.