The Denser the Merrier?

The coronary artery calcium (CAC) score, the Agatston score, is a robust noninvasive surrogate marker of coronary atherosclerosis, which is strongly associated with increased risk of incident cardiovascular events and mortality.1 Its ability to predict adverse cardiovascular outcome is incremental to traditional risk factors used in clinical risk prediction,2,3 and it has been validated by studies on a wide spectrum of sex, age, ethnic, and racial backgrounds.1,4 The association between vascular calcification and worse prognosis has also been documented in other extracoronary vascular territories.5,6 In particular, the presence and extent of abdominal aortic calcification (AAC), measured using the Agatston method, is associated with a higher risk of incident cardiovascular events and mortality in several studies.7See Article by Forbang et al The Agatston score has been developed to quantify the total amount of vessel calcification, and it is calculated by multiplying the calcification area by a density factor.8 This calculation assumes that any increase in the amount of calcification would indicate a higher atherosclerosis burden and worse prognosis. Yet, recent studies have questioned whether both components of the score, calcification area and density, have similar implications for prognosis.In a previous analysis of MESA (Multi-Ethnic Study of Atherosclerosis),9 the investigators estimated the averaged CAC density by dividing the Agatston CAC score by the CAC volume. In this study, the coronary calcium …