Abstract 13863: Computed Tomography Angiography Characteristics of Thin-Cap Fibroatheroma in Patients With Diabetes Mellitus

Abstract

Background: It was recently reported that thin-cap fibroatheroma (TCFA) detected by optical coherence tomography (OCT) was an independent predictor of future cardiac events in patients with diabetes mellitus. However, OCT requires invasive procedure including intracoronary imaging. Computed tomography angiography (CTA) characteristics of TCFA have not been systematically studied. Aims: The aim of this study was to investigate CTA characteristics of TCFA in patients with diabetes mellitus. Methods: Patients with diabetes mellitus who underwent pre-intervention CTA and OCT were enrolled. Non-culprit lesions with a diameter stenosis of ≥30% on angiogram were assessed. Plaque volume and high-risk plaque (HRP) features were evaluated by CTA. Results: Among 132 plaques in 106 patients with diabetes mellitus, 31 plaques had TCFA. Fibrofatty and necrotic core (FF + NC) volume (-30 to 130 HU) was higher in TCFA than in non-TCFA (125.5 mm 3 vs. 59.4 mm 3 , p <0.001). The prevalence of positive remodeling (90.3% vs. 44.6%, p <0.001), low attenuation plaque (80.6% vs. 28.7%, p <0.001), and napkin-ring sign (77.4% vs. 11.9%, p <0.001) was significantly higher in TCFA than in non-TCFA. The difference in the prevalence of spotty calcification between TCFA and non-TCFA was not statistically significant (19.4% vs. 15.8%, p = 0.608). In multivariable logistic regression analysis, FF + NC volume ≥103.7 mm 3 (OR: 6.8; P <0.001) and HRP features ≥2 (OR: 11.7; P <0.001) were associated with TCFA. The addition of FF + NC volume ≥103.7 mm 3 to HRP features ≥2 significantly increased the area under the curve for detection of TCFA (AUC = 0.766 [95% CI; 0.673-0.859] vs AUC = 0.820 [95% CI; 0.736-0.904]; p = 0.012). Conclusions: FF + NC volume and HRP features on CTA were associated with OCT-detected TCFA. CTA may be helpful in identifying high-risk plaques in patients with diabetes mellitus.