Prevalence and Significance of Obstructive Coronary Artery Disease in Patients with Zero Coronary Artery Calcium Score

Abundant data have established coronary artery calcium score (CACS) in the algorithm of cardiovascular risk stratification, especially for those at intermediate risk of coronary artery disease (CAD). Absence of CACS is associated with a very low cardiac event rate in asymptomatic individuals and no further imaging is required. Cardiac event rates in symptomatic patients are comparatively higher but still relatively low and have to be interpreted in the context of the population included. Conflicting results from angiography literature with a reported presence of obstructive CAD in up to 39% of mostly symptomatic patients with zero CACS are explained by the higher-risk patients enrolled. CACS is an excellent test for asymptomatic patients in predicting cardiac events and absence of obstructive CAD but has a limited role in symptomatic and higher-risk patients encountered by a cardiovascular specialist, particularly those referred for CT angiography and invasive coronary angiography. This is especially true for relatively young patients (<45 years of age).