Abstract 903: Low Plasma Adiponectin Level and High Oxidative Stress are Associated with In Vivo Thin-Cap Fibroatheloma Prevalence in Patients with Stable Coronary Artery Disease

Abstract

Background ; Few studies have investigated the association between biomarkers and in vivo plaque vulnerability in patients with stable coronary artery disease (CAD). Methods ; We examined two or three vessels of 55 stable CAD patients with combined use of virtual histology intravascular ultrasound (VH-IVUS) and optical coherence tomography (OCT), and diagnosed thin-cap fibroatheroma (TCFA). The definition of TCFA was described as follow: necrotic core rich lesion (%necrotic-core>10%) without evident overlying fibrous component and %plaque-volume>40% by VH-IVUS analysis, and the thinnest fibrous-cap thickness <65μm by OCT measurement. The patients were divided into two groups, the patients with TCFA and without TCFA, and compared their clinical characteristics, laboratory data and new atherosclerotic biomarkers (adiponectin, oxidative stress marker) between these two groups. Results ; In 55 patients, we could observe 126 vessels (2.29±0.46 vessel/patient) with both modality and we identified 37 TCFA in them. At least one TCFA was identified in 24 patients (43.6%) and not in 31 patients. There were no differences in the clinical characteristics between the two groups. However, a greater number of patients with TCFA had a past history of ACS than those without TCFA (P=0.04). As for laboratory data, there were no differences in lipid and sugar profiles and inflammatory markers, but patients with TCFA had lower plasma adiponectin levels and higher urine- 8-isoprostane/creatinine levels, which is considered as reliable in vivo oxidative stress marker, than patients without TCFA (p=0.0002, P=0.04, respectively). Multivariate logistic regression analysis revealed the most powerful indicative factor of TCFA prevalence in stable CAD was plasma adiponectin levels (P=0.001). The receiver-operating characteristic curve analysis identified plasma adiponectin <6.8μg/ml (Area under curve = 0.80, 95% confidence interval = 0.67 to 0.90, P=0.0001, sensitivity 70.8%, specificity 80.6%) as the optimal cut-off point for prediction of the TCFA prevalence in stable CAD. Conclusion ; Plasma adiponectin levels and urine-8-isoprostane may be one of the tools that help to stratify vulnerable patients into risk categories in patients with stable CAD.