Circulating Endothelial Progenitor Cells were Increased in Patients with Thin-Cap Fibroatheroma.

BACKGROUND

We used virtual histology-intravascular ultrasound (VH-IVUS) to evaluate the relationship between circulating endothelial progenitor cells (EPC) and thin-cap fibroatheroma (TCFA).

METHODS

This study included 52 patients with unstable angina who underwent coronary angiography and IVUS examination. Patients were divided into a TCFA group (n = 21) or a non-TCFA group (n = 31) based on VH-IVUS performance. Before angiography, peripheral blood levels of EPC were measured by flow cytometry. TCFA was defined as a necrotic core (NC) ≥ 10% of the plaque area without overlying fibrous tissue in the presence of ≥ 40% plaque burden.

RESULTS

Levels of circulating EPCs were 72.45 ± 31.73 (count/105) in the TCFA group and 23.93 ± 11.87 (count/ 105) (p < 0.01). Mean levels of CRP were 0.38 ± 0.21 mg/L in the TCFA group and 0.23 ± 0.17 mg/L (p < 0.01). Levels of EPCs correlated positively with necrotic core volume(r = 0.421, p = 0.005), CRP (r = 0.405, p = 0.011) and negatively with fibrous tissue volume(r = -0.411, p = 0.009). In multivariate logistic regression analysis, level of EPC (OR: 1.815, 95% CI: 1.12 - 2.798, p = 0.016), plaque burden (OR: 1.26, 95% CI: 1.07 - 1.86, p = 0.027), and CRP (OR; 1.14, 95% CI: 0.74 - 1.56, p = 0.029) were independent predictors of TCFA.

CONCLUSIONS

Circulating EPCs were increased in patients with TCFA, level of EPCs could predict the presence of TCFA.