CT Coronary Angiography for Evaluation of Subclinical Atherosclerosis in Patients with High-Risk Metabolic Syndrome

Abstract

ABSTRACT

Background:
Metabolic syndrome (MetS) is a major driver of premature atherosclerotic cardiovascular disease, particularly in South Asian populations. Conventional risk scores often fail to detect early or subclinical coronary disease in high-risk individuals. Coronary CT angiography (CCTA) enables direct visualisation and quantification of coronary plaque, including high-risk morphology. This study evaluates the role of CCTA in detecting subclinical atherosclerosis among adults with high-risk MetS.

Methods:
This cross-sectional observational study included 100 adults diagnosed with MetS (NCEP-ATP III criteria) and classified as high-risk based on ≥4 MetS components, long-standing MetS, or additional atherosclerotic risk enhancers. All participants underwent contrast-enhanced CCTA on a ≥64-slice CT scanner. Plaque presence, type, burden (segment involvement score, SIS), stenosis severity, high-risk plaque features, and coronary artery calcium score (CACS) were assessed. Metabolic parameters were correlated with plaque burden.

Results:
Subclinical coronary atherosclerosis was detected in 72% of patients. Plaque prevalence rose significantly with MetS severity (40.9% in mild vs 92.5% in severe; p < 0.001). Calcified (22.7% vs 60%; p = 0.004) and non-calcified plaques (9.1% vs 42.5%; p = 0.008) increased across severity categories. High-risk plaque features were present in 32.5% of severe MetS subjects compared with 4.5% in mild (p = 0.003). Median CACS (42 to 152; p < 0.001) and mean SIS (0.9 ± 0.7 to 3.0 ± 1.4; p < 0.001) also increased markedly. Luminal stenosis ≥50% occurred in 40% of severe MetS patients but was absent in mild cases. Plaque burden showed significant correlations with fasting glucose (r = 0.42), triglycerides (r = 0.38), waist circumference (r = 0.36), BMI (r = 0.29), and HDL (r = –0.31). MetS severity score demonstrated the strongest association (ρ = 0.55; p < 0.001).

Conclusion:
Subclinical coronary atherosclerosis is highly prevalent in high-risk MetS patients, with plaque burden and high-risk features rising sharply with metabolic severity. CCTA offers substantial value in early detection and risk stratification, surpassing traditional clinical and biochemical markers. Incorporating CCTA into evaluation algorithms for high-risk MetS populations may facilitate earlier preventive interventions. Prospective studies are required to determine the impact of CCTA-guided management on long-term cardiovascular outcomes.