Coronary Atherosclerosis in an Asymptomatic U.S. Population: Miami Heart Study at Baptist Health South Florida

BACKGROUND: The burden of total coronary plaque, plaque subtypes, and high-risk plaque features was unknown in asymptomatic individuals from the general U.S. primary prevention population.

OBJECTIVES: In a large, asymptomatic U.S. cohort evaluated using coronary computed tomography angiography (CCTA), we aimed to assess the burden of total coronary plaque, plaque subtypes, and high-risk plaque features; the interplay between CCTA findings and coronary artery calcium (CAC) scores; and identify independent predictors of coronary plaque.

METHODS: Cross-sectional analysis in the MiHeart (Miami Heart Study), a cohort of 2,359 asymptomatic individuals from the Greater Miami Area (mean age 53 years, 50% women, 47% Hispanic/Latino, 43% non-Hispanic White). We estimated the burden of CAC (=0, >0 to <100, ≥100), CCTA-based plaque features (any plaque, stenosis ≥50%, ≥70%, high-risk features), and their interplay.

RESULTS: Overall, 58% participants had CAC = 0, 28% CAC >0 to <100, and 13% CAC ≥100. A total of 49% participants had plaque on the CCTA, including 16% among those with CAC = 0. Overall, 6% participants had coronary stenosis ≥50% (12% among those with coronary plaque), 1.8% had stenosis ≥70% (3.7% among those with plaque), and 7% had at least 1 coronary plaque with ≥1 high-risk feature (13.8% among those with plaque). Only 0.8% participants with CAC = 0 had stenosis ≥50%, 0.1% stenosis ≥70%, and 2.3% plaque with high-risk features. In logistic regression models, independent predictors of coronary plaque and high-risk plaque were older age, male sex, tobacco use, diabetes, overweight, and obesity. Male sex, overweight, and obesity were independent predictors of plaque if CAC = 0.

CONCLUSIONS: The Miami Heart Study confirms substantial prevalence of coronary plaque in asymptomatic individuals. Overall, 49% of participants had coronary plaque, 6% had stenosis ≥50%, and 7% had plaques with at least 1 high-risk feature. These proportions were 16%, 0.8%, and 2.3%, respectively, among those with CAC = 0. Longitudinal follow-up will shed further light on the prognostic implications of these findings in asymptomatic individuals.