Coronary Calcium Score and Cardiovascular Risk

Abstract

Coronary artery calcium (CAC) is a highly specific feature of coronary atherosclerosis. On the basis of single-center and multicenter clinical and population-based studies with short-term and long-term outcomes data (up to 15-year follow-up), CAC scoring has emerged as a widely available, consistent, and reproducible means of assessing risk for major cardiovascular outcomes, especially useful in asymptomatic people for planning primary prevention interventions such as statins and aspirin. CAC testing in asymptomatic populations is cost effective across a broad range of baseline risk. This review summarizes evidence concerning CAC, including its pathobiology, modalities for detection, predictive role, use in prediction scoring algorithms, CAC progression, evidence that CAC changes the clinical approach to the patient and patient behavior, novel applications of CAC, future directions in scoring CAC scans, and new CAC guidelines.

Keywords: aspirin; atherosclerotic cardiovascular disease; coronary artery calcification; coronary heart disease; statins.

Figure 1. Associations of CAC Area With Plaque Area (Plaque Burden) Per Patient

(A) Calcium area with plaque area (per artery). (B) CAC is highly correlated with plaque burden, both at the level of the individual artery and in the heart as a whole. Reprinted, with permission, from Rumberger et al. (36) CAC = coronary artery calcium.

Figure 1. Associations of CAC Area With Plaque Area (Plaque Burden) Per Patient

(A) Calcium area with plaque area (per artery). (B) CAC is highly correlated with plaque burden, both at the level of the individual artery and in the heart as a whole. Reprinted, with permission, from Rumberger et al. (36) CAC = coronary artery calcium.

Figure 2. Cardiovascular Event Rate for HNR Study Participants

The cardiovascular event rates for participants in the HNR study with and without statin indication according to ESC and ACC/AHA guidelines are shown, stratified by CAC. Group. There figure shows a distinct increase in cardiovascular event rates with increasing CAC score, irrespective of statin indication according to ESC and ACC/AHA guidelines. Reprinted, with permission, from Mahabadi et al. (92). ACC/AHA = American College of Cardiology/American Heart Association; CAC = coronary artery calcium; ESC = European Society for Cardiology; HNR = Heinz Nixdorf RECALL.

Figure 3. Estimated Risk/Benefit of Aspirin in Primary Prevention by CAC Score in MESA Participants

The estimated risk/benefit of aspirin in primary prevention by CAC score in MESA participants is shown. Coronary heart disease (CHD) risk was calculated using the Framingham Risk Score. The red line represents the estimated 5-year number needed to harm based on a 0.23% increase in major bleeding over 5 years. The 5-year number needed to treat estimations are based on an 18% relative reduction in CHD events. In patients with CAC = 0, aspirin was not estimated to be beneficial, regardless of estimated CHD risk. Conversely, when CAC >100, aspirin was estimated to provide net benefit, regardless of CHD risk estimate. Reprinted, with permission, from Miedema et al. (94). CAC = coronary artery calcium; MESA = Multi-Ethnic Study of Atherosclerosis.