CXCL9: a biomarker for the coronary slow flow phenomenon in patients with coronary artery disease

Abstract

Background: Atherosclerosis is a chronic inflammatory disease. The pathology underlying the disease consists of accumulation of the extracellular matrix, lipid and inflammatory cells. Coronary Slow Flow Phenomenon (CSFP) is closely related to inflammatory responses, while chemokines play an important role in the progression of atherosclerosis. However, the relationship between chemokines and CSFP is unclear. In this study, our aims were to evaluate the association between CXC Chemokines 9 (CXCL9) levels and CSFP in patients with coronary artery disease. Methods: We studied 46 patients diagnosed with CSFP and classed them as the CSFP group. 50 patients with normal coronary angiography (CAG) were randomly selected as the no-CSFP group in our study. The mean TIMI frame count was used to measure coronary blood flow velocity. The clinical and biochemical index, including serum levels of IL1, IL-6, IL-10, CXCL9, CD40L and interferon-γ (IFN-γ), were analyzed in all subjects. Results: The serum levels of IL-1, IL-6, IL-10, CXCL9, CD40L, IFN-γ and CXCL9 in the CSFP group were significantly higher than those in the no-CSFP group, with the differences being statistically significant (p<0.001). Furthermore, Pearson's correlation analysis reflected a significant positive correlation (r=0.171, p=0.01) in CXCL9 levels. Multivariate logistic regression analysis showed that CXCL9 are important risk factors for CSFP (β=1.795, P=0.000). Subsequent ROC curve analyses indicated that the serum CXCL9 levels demonstrated a high diagnostic value in differentiating patients with CSFP from that of normal controls (Area Under the Curve = 0.758) and the serum CXCL9 level of 131.915 mg/L was a predictor of CSFP, with a sensitivity of 54.3% and a specificity of 96.0%. Conclusions: Our findings are indicative of the potential clinical implications of CXCL9 in the occurrence and development of CSFP.