Pericardial fat inflammation correlates with coronary artery disease

Objectives: We sought to assess the association between inflammation in pericardial fat (PF) and coronary artery disease (CAD) by pathological examination and clinical evaluation with cardiac computed tomography (CT).

Background: Inflammation of adipose tissue is involved in cardio-metabolic disorders and shows high density in CT.

Methods: We quantified, by immunohistochemical means, the PF inflammation in 39 autopsy cases by counting leukocyte common antigen (LCA)-positive cells. We then measured the CT density of PF in 39 patients with acute coronary syndromes and 69 patients suspected of CAD.

Results: Pericoronary PF had significantly more LCA-positive cells in CAD autopsy cases (n=21) than non-CAD cases (n=18) (44 ± 21 vs. 24 ± 22 cells/mm(2), p=0.006). The CT density of PF around culprit lesions was significantly higher than non-culprit lesions in patients with acute coronary syndromes (-72 ± 11 vs. -82 ± 14 HU, p=0.002), which may reflect PF inflammation. Among patients suspected of CAD, the pericardial CT density gradient (PDG; difference in CT density between pericoronary PF and PF apart from coronary arteries) was significantly greater in CAD patients (n=30) than non-CAD patients (n=39) (22 ± 16 vs. 16 ± 10 HU, p=0.046). Multiple logistic regression analysis demonstrated that the PF inflammation index (PFI; PDG × PF volume, which could be the integrated index of inflammatory activity and abundance of PF) was significantly associated with the presence of CAD (odds ratio [95% confidence interval]; 1.234 [1.012-1.503] per 1000 HU cm(3), p=0.037) independent of other metabolic risk factors such as hypertension, dyslipidemia, and diabetes.

Conclusions: Active inflammation in PF correlates with CAD. PF inflammation may be involved in pathogenesis of CAD.