JCL roundtable: Coronary artery calcium scoring and other vascular imaging for risk assessment

Computed tomographic (CT) coronary calcium scoring has been established by large prospective, population-based studies as the single best noninvasive predictor of atherosclerotic cardiovascular risk available today. The calcium score correlates highly with the total burden of coronary atherosclerosis demonstrated at autopsy. It adds significantly to traditional risk calculators such as the Framingham Risk Calculator or the Pooled Cohort Equations. The 2018 U.S. Cholesterol Guidelines endorse the use of CT coronary calcium scoring to refine risk estimates in the intermediate range of 7.5%–20% over 10 years. Most, but not all, adults with calcium scores of zero can reasonably elect to avoid or defer statin therapy, but repeating the calcium score should be considered in 5 to 10 years. Discussants at this roundtable urge that coronary calcium scoring be offered to many more adults than currently receiving this test, including those with borderline 10-year risk in the range of 5%–7.5%. CT coronary angiography is a procedure based on intravenous contrast injection, mostly used in low-risk patients with chest pain. In British guidelines, CT angiography is preferred over stress testing for initial assessment of suspected coronary symptoms. Carotid ultrasound evaluating both the carotid intima-media thickness and presence of plague is less predictive than coronary calcium scoring for overall atherosclerotic risk but more predictive for stroke risk.