The presence of coronary<unk>  calcification indicates underlying CHD. The coronary<unk><unk>  (CAC) scan is a non-contrast CT scan used to visualize the extent of calcification in the coronary vessels. While there is a strong correlation between CAC burden and coronary plaque area, CAC scans do not identify noncalcified plaques that are capable of erosion or rupture and therefore may not be a good predictor of luminal obstruction. 
The role of CAC in patients with low or intermediate risk of developing a CHD event is uncertain. However, it is not indicated for patients at high risk of CHD as aggressive preventative measures would have already been initiated.
Coronary artery calcium scoring
Quantitative coronary angiography
Coronary computed tomography
Coronary angiography quantitative angiography
Cardiac electrophysiology
Fractional flow reserve
TIMI frame count 
Canadian cardiovascular society classification of angina pectoris