Abstract 14650: Risk Stratifying Individuals With Zero, Minimal, and Mild Coronary Artery Calcium for Cardiovascular Disease by Determining Coronary Plaque Burden

Background and Aims: Previous research has often categorized minimal CAC (1-10) and 0 CAC into a single low-risk category for CVD. However, the clinical significance of plaque burden between these two groups remains unclear. We sought to determine the plaque burden in individuals with CAC scores of 0, 1-10, and 11-100 to specify a more accurate risk stratification for minimal and 0 CAC scores.

Methods: Retrospectively reviewed patients with CAC scores ≤100 and performed quantitative coronary plaque analysis (QAngio, Medis). CAC was categorized into three groups: zero (CAC=0), minimal (CAC 1-10), and mild (CAC 11-100). Plaque levels (low attenuated, fibrous, fibro-fatty, dense calcified, total non-calcified) were assessed using multivariable linear regression adjusted for cardiovascular risk factors (age, ethnicity, BMI, gender, hypertension, dyslipidemia, diabetes mellitus, past smoking)

Results: 378 subjects were included, with an average age of 53.9±10.7 years and 53% female. Among them, 51% had 0 CAC, 16% had minimal CAC (scores 1-10), and 33% had mild CAC (scores 11-100). The minimal and mild CAC groups were significantly older, with higher rates of diabetes, hypertension, and hyperlipidemia. Multivariable analysis found no significant difference in low attenuated, fibro-fatty, and dense calcified plaque levels between the minimal and 0 CAC groups. However, minimal CAC subjects had significantly higher fibrous, total non-calcified, and total plaque volumes than zero CAC ( Table 3 ). All plaque types were significantly higher in the mild group when comparing mild CAC to minimal CAC."

Conclusion: This study shows higher noncalcified coronary plaque and total plaque volume in individuals with minimal calcium scores (1-10) compared to those with 0 CAC. These findings hold clinical significance, challenging previous categorization of minimal CAC as low-risk. Therefore, those with minimal CAC scores need a more accurate risk stratification approach.