Background: hs-CRP (high sensitive C-reactive protein) has been known as a systemic inflammatory marker of atherosclerosis and considered as one of the predictors of future cardiac events. Some reports presented hs-CRP level was associated with plaque vulnerability but most studies were performed by assessing focal target plaque but not whole plaques from a coronary tree.
Methods: To evaluate of the relationship of plasma hs-CRP level and volumetric plaque composition of the coronary arterial tree, we performed ‘whole vessel” virtual histology-intravascular ultrasound (VH-IVUS) in 189 vessels of 63 patients. The components of atherosclerosis were classified as fibrous (FI), fibrous-fatty (FF), necrotic core (NC) and dense calcium (DC). Quantitative assessment of these plaque components and the presence of VH-IVUS–derived thin-cap fibroatheroma (VH-TCFA) in the coronary arterial trees were compared to hs-CRP levels in individuals. hs-CRP levels were measured before coronary angiogram and IVUS study.
Results: Forty-nine patients (77.8%) were diagnosed with acute coronary syndrome in this population. The mean values of hs-CRP were 0.24±0.52 mg/dl (0~3.27mg/dl). The analyzed vessel length was 56.1±17.4 mm for the left anterior descending coronary artery, 51.9±19.0 mm for the left circumflex coronary artery, and 74.2±18.8 mm for the right coronary artery. The number of VH-TCFAs was 1.0±0.8 for the left anterior descending, 0.6±0.7 for the left circumflex, and 0.8±1.0 for the right coronary arteries.The hs-CRP levels were positively correlated to mean plaque burden, total plaque volume index, volume index of FF and DC. But parameters of NC and the number of VH-TCFA were not related with hs-CRP level. In multivariate analysis, the volume index of DC was most reliable factor to hs-CRP (β=3.646, CI=2.036 to 5.255, p<0.001) Conclusions: This three-vessel VH-IVUS presented that hs-CRP were related to the total atherosclerotic burden and the maturing (coronary calcium) but not vulnerable features (NC or VH-TCFA) of plaques in coronary arterial tree. Increased hs-CRP level as a biomarker to predict cardiovascular events might imply atherosclerosis severity of whole coronary tree but not current plaque vulnerability.