Noncalcified coronary plaque volumes in healthy people with a family history of early onset coronary artery disease.

Background: Although age and sex distributions of calcified coronary plaque have been well described in the general population, noncalcified plaque (NCP) distributions remain unknown. This is important because NCP is a putative precursor for clinical coronary artery disease and could serve as a sentinel for aggressive primary prevention, especially in high-risk populations. We examined the distributions of NCP and calcified coronary plaque in healthy 30- to 74-year-old individuals from families with early onset coronary artery disease.

Methods And Results: Participants in the GeneSTAR family study (N=805), mean age 51.1±10.8 years, 56% women, were screened for coronary artery disease risk factors and coronary plaque using dual-source computed tomographic angiography. Plaque volumes (mm(3)) were quantified using a validated automated method. The prevalence of coronary plaque was 57.8% in men and 35.8% in women (P<0.0001). NCP volume increased with age (P<0.001) and was higher in men than women (P<0.001). Although NCP, as a percentage of total plaque, was inversely related to age (P<0.01), NCP accounted for most of the total plaque volume at all ages, especially in men and women <55 years (>70% and >80%, respectively). Higher Framingham risk was associated with the number of affected vessels (P<0.01), but 44% of men and 20.8% of women considered intermediate risk had left main and 3-vessel disease involvement.

Conclusions: The majority of coronary plaque was noncalcified, particularly in younger individuals. These findings support the importance of assessing family history and suggest that early primary prevention interventions may be warranted at younger ages in families with early onset coronary artery disease.