Coronary Artery Calcium: If Measuring Once Is Good, Is Twice Better?

Abstract

Article, see p 665 > You’re always you, and that don’t change , > > and you’re always changing, and there’s nothing you can do about it . > > —Neil Gaiman, The Graveyard Book Atherosclerosis is a dynamic process that is constantly changing and morphing. Unchecked, this constant change can lead to advancement and disruption, culminating in ischemic heart disease and myocardial infarction. However, this dynamic nature also offers opportunities to intervene with preventive therapies to halt or reverse course before these adverse outcomes occur. These properties also offer the allure of quantifying change in atherosclerosis to better pinpoint and personalize atherosclerotic cardiovascular disease (ASCVD) risk estimates. Several novel screening tests have been evaluated to improve ASCVD risk assessment; of these tests, coronary artery calcium (CAC) scanning has emerged as the top contender. High CAC scores are associated with a markedly increased risk of coronary heart disease (CHD) (4- to 10-fold higher) independent of other risk factors, and CAC has been shown to improve clinical reclassification of CHD and ASCVD risk.1–3 In addition, those with no CAC have a relatively good prognosis and may consider deferring preventive therapies such as statins.4 There has been growing interest in exploring whether repeat CAC scanning, thereby evaluating change in the CAC score, could enhance cardiovascular risk prediction. An early study from 2004 suggested that change in CAC may be a meaningful and additive contribution to predicting an individual’s risk.5 However, only in the last several years have population-based studies become available with paired scans and adequate numbers of ASCVD events.6,7 Using MESA (Multi-Ethnic Study of Atherosclerosis), Budoff et al6 examined the relationship of CAC progression to CHD outcomes in …