BACKGROUNDThe relationship between inflammatory markers and the characteristics of coronary atherosclerosis plaques is uncertain. The aim of the present study was to evaluate the relationship between the characteristics of coronary atherosclerosis plaques and inflammatory markers such as high sensitivity C-reactive proteins (Hs-CRP) and interleukin-6 (IL-6).

METHODSAll patients suspected of having coronary heart disease (CHD) underwent Siemens 64-slice CT angiography (64-SCTA) to distinguish the quality of plaque of coronary artery lesions. Blood samples were taken to measure levels of serum Hs-CRP and IL-6 in different plaque groups and the control group and compared with the value of 64-SCTA for detection of coronary artery plaque.

RESULTSThe sensitivity of detecting coronary artery plaque by 64-SCTA was 87.4%, the specificity was 87.1%, the positive predictive value was 82.2%, and the negative predictive value was 91.0%. Comparing the levels of serum Hs-CRP and IL-6 among plaque groups, the mean levels of serum Hs-CRP and IL-6 in three plaque groups were significantly higher than those in the control group (P < 0.01). The mean levels of serum Hs-CRP and IL-6 in the soft plaque group and mixed plaque group were significantly higher than those in hard plaque group (P < 0.01). Plaque burden in the soft plaque group and mixed plaque group was significantly higher than in the hard plaque group (P < 0.01), but there was no statistical difference between the soft plaque group and mixed plaque group (P = 0.246). There was a negative correlation between the CT scale and Hs-CRP and IL-6 levels in the soft plaque group (r = -0.621, P < 0.01, and r = -0.593, P < 0.01 respectively). There was a positive correlation between the plaque burden and Hs-CRP and IL-6 levels in the soft plaque group (r = 0.579, P < 0.05 and r = 0.429, P < 0.05 respectively).

CONCLUSIONS64-SCTA is an effective way to distinguish the different quality of coronary atherosclerosis plaque. Serum Hs-CRP and IL-6 levels can be considered as the indexes to judge the degree of CHD and may reflect the activity of plaque in CHD patients. Thus it is important for clinical diagnosis and risk evaluation of acute coronary syndrome (ACS) patients.