Abstract 19364: Coronary Plaque Characteristics by Age and Sex in Healthy Individuals with a Family History of Early-Onset Coronary Artery Disease

Abstract

Background: Although calcified coronary plaque (CCP) increases with age and is more prevalent in males, the extent to which noncalcified plaque (NCP) is present across the age range of both sexes is unknown. This has important implications for primary prevention guidelines, particularly in high risk populations, since NCP is a putative immediate precursor for coronary artery disease (CAD) events. We thus examined total coronary plaque (TCP), CCP, and NCP distributions in healthy male and female first degree relatives of persons with early-onset CAD. Methods: Participants in GeneSTAR (N=561), mean age 51.5 ± 10.8 years, range 30 to 75 years, 58% female, were screened for coronary plaque using 256 multidetector dual-source CT angiography. Segmental plaque volumes (mm3) were quantified using an automated well-validated proprietary method and summed for CCP and NCP. TCP was calculated from CCP+NCP. Results: Males had a higher prevalence of any coronary plaque compared to females, (58.1% vs 36.7% respectively, p<0.0001); plaque prevalence increased significantly with age (Table). However, females more often had only NCP than males, (17.6% vs 8.9%, p= 0.11). CCP and NCP volumes both increased with age in both sexes, but NCP accounted for more than half of TPV in both sexes at all ages; NCP represented more than 80% of TPV in subjects <55 years of age. Conclusion: The majority of TPV was noncalcified plaque in this healthy high risk population, particularly in females and in males <55 years old. Thus, conditioning aggressive primary prevention on traditional coronary calcium scoring algorithms, may obviate appropriate risk reduction interventions in young persons with a family history of early onset-CAD. Table: Sex-specific noncalcified and calcified coronary plaque volumes by age group (median [IQR])