A negative test (score = 0) makes the presence of atherosclerotic plaque, including unstable or vulnerable plaque, highly unlikely
A negative test (score = 0) makes the presence of significant luminal obstructive disease highly unlikely (negative predictive power by EBCT approximately 95–99%).
A negative test is consistent with a low risk (0.1% per year) of a cardiovascular event in the next 2–5 years.
A positive test (CAC > 0) confirms the presence of a coronary atherosclerotic plaque.
The greater the amount of coronary calcium, the greater the atherosclerotic burden in men and women, irrespective of age.
The total amount of coronary calcium correlates best with the total amount of atherosclerotic plaque, although the true “atherosclerotic burden” is underestimated.
A high calcium score (an Agatston score > 100) is consistent with a high risk of a cardiac event within the next 2–5 years (> 2% annual risk).
CAC measurement can improve risk prediction in conventional intermediate-risk patients, and CAC scanning should be considered in individuals at intermediate risk for a coronary event (1.0% per year to 2.0% per year) for clinical decision-making with regard to refinement of risk assessment.
Decisions for further testing (such as stress testing or cardiac catheterization) beyond assistance in risk stratification in patients with a positive CAC score cannot be made by coronary calcium scores alone, as calcium score correlates poorly with stenosis severity in a given individual and should be based on clinical history and other conventional clinical criteria.
