Objective: T he aim of this study was to investigate the association between eccentricity index (EI), de-termined using Computed Tomography Angiography (CTA), and coronary plaque features in patients with unstable angina.
Methods: The study enrolled 80 patients with unstable angina in whom CTA was performed and demonstra-ted significant stenosis (≥50% luminal narroring) and at least one vulnerable character associated with plaque morphology, such as: PR – defined as a remodeling in-dex (RI) ≥1.1, LAP with <50 Hounsfield Units, presence of NPS or SC. Eccentricity index (EI) was calculated as: (maximum wall thickness – minimum wall thickness)/ maximum wall thickness. Eccentric lesions were defi-ned as having an EI ≥0.3, while concentric lesions were defined as having an EI <0.3.
Results: Forty lesions were identified as eccentric and forty as concentric. We identified that the presence of two vulnerable features was significantly higher in pa-tients with eccentric lesions as compared with patients with concentric lesion: spotty calcifications 39% vs. 26%, p=0.03, Odds ratio 3.1 (95% CI: 1.1 – 8.2) and low attenuation plaque 25% vs. 13%, p=0.03, Odds ratio 3 (95% CI: 1.1-7.7).
Conclusions: Patients with unstable angina and excen-tric plaques present more spotty calcifications and low attenuation plaques. Eccentricity index could serve as an indicator of plaque vulnerability and could become a predictor of future cardiac events.