Abstract 15626: Inflammatory Burden of Peri-Coronary Adipose Tissue May Affect Plaque Destabilization in Patients with Non ST Segment Myocardial Infarction
Background: Extravascular expression of inflammatory mediators may adversely influence coronary lesion formation and plaque stability. Maximal standardized uptake value (SUV) of 18-fluorodeoxyglucose (FDG) detected by positron emission tomography in peri-coronary adipose tissue (PVAT) has been shown to be greater in patients with stable coronary artery disease, than in controls, and to correlate with % of coronary stenosis. We sought to investigate, whether PVAT may influence plaque composition in Non ST Segment Myocardial Infarction (NSTEMI) patients.
Methods: 36 coronary arteries (LM, RCA, LCX, LAD) have been investigated in non-diabetic patients with moderate and low risk NSTEMI (GRACE <140). SUV was measured in fat around arteries on the sections corresponding to proximal and medial segments. PVAT thickness was measured in two perpendicular dimensions on axial cuts separately for the LM, RCA, LAD and LCX, using steady state free precession cine imaging. Additionally SUV was measured in subcutaneous fat (SC), visceral thoracic fat (VS), epicardial fat over right ventricle (EPI). Conventional and virtual histology intravascular ultrasound (VH-IVUS) was performed to assess plaque composition, which were classified as calcified, fibrous, fibro-fatty, or necrotic core. PET/CT sections were further examined in segments corresponding to coronary plaques.
Results: PVAT SUV in NSTEMI patients was significantly greater than in other fat locations (LM SUV: 1.60; RCA SUV: 1.54; LCX SUV: 1.94 LAD SUV: 2.37 vs SC SUV: 0.57; VS SUV: 0.77; EPI SUV: 0.98, p<0.001; ANOVA). There was no significant correlation between PVAT thickness and plaque composition. In contrast PVAT SUV positively correlated with necrotic core plaque rate (r = 0.68, p<0.05), and negatively correlated with fibrous plaque rate (r=-0.52, p<0.05). There was also positive correlation between PVAT SUV and % plaque volume (r=0.40, p<0.05).
Conclusions: Inflammatory burden of peri-coronary adipose tissue is greater than in subcutaneous, visceral thoracic, or epicardial tissue in NSTEMI patients; There is no association between amount of pericoronary fat and plaque composition; PVAT SUV correlates with necrotic core component of coronary plaque and plaque volume in patents with NSTEMI.
- © 2012 by American Heart Association, Inc.