Perivascular fat attenuation index and high-risk plaque features evaluated by coronary CT angiography: relationship with serum inflammatory marker level.

The present study aimed to investigate the association between perivascular fat attenuation index (FAI), high-risk plaque features and serum level of high sensitive C-reactive protein (hs-CRP). Consecutive patients with intermediate pre-test probability of CAD, who were referred for coronary CT angiography (CCTA), were included. High-risk plaque features were assessed by CCTA and included low attenuation plaque (LAP), positive remodeling (PR), napkin-ring sign (NRS) and spotty calcification. Lesion specific perivascular FAI was also measured for all plaques located on major epicardial vessels with diameter ≧ 2 mm. Laboratory test results, including hs-CRP, were recorded. 199 patients with 260 lesions were finally included. NRS and LAP were more commonly present in the group with elevated hs-CRP (35.9% vs. 19.4% and 14.1% vs. 2.6%, both p < 0.05) and more severe stenosis extent was also noted for this group. However, there was no significant difference between the elevated hs-CRP and normal hs-CRP group with respect to other CT parameters, such as lesion length, PR, spotty calcification and focal calcium score. Perivascular FAI failed to show significant difference between the two groups (- 69.8 ± 10.3HU vs. - 70.0 ± 12.0HU, p = 0.953) and there was poor correlation between perivascular FAI and hs-CRP measurements (r =  - 0.04, p = 0.510). In conclusion, LAP and NRS are more commonly present in CAD patients with elevated level of hs-CRP. However, perivascular FAI failed to show such correlation with serum level of hs-CRP.