Assessment of atherosclerotic plaques using FDG-PET

Abstract

Atherosclerosis is widely accepted as a chronic inflammatory disorder. However it was impossible to visualize non-invasively inflammation of individual plaques. We have reported that 18 [F]-fluorodeoxyglucose (FDG) uptake, namely inflammation, can be detected quantitatively in carotid or aortic plaques using FDG-positron emission tomography (PET) imaging co-registered with computed tomography (CT) (FDG-PET/CT). Of patients who had the ultrasound-proven carotid atherosclerosis without recent cerebrovascular events, approximately 30% showed FDG uptake in the carotid artery by assessing PET/CT imaging. In patients who underwent FDG-PET/CT imaging for cancer screening and had no recent cerebrovascular events, the intensity of carotid inflammation was well associated with the components of the metabolic syndrome (positively with body circumference and HOMA-RI; negatively with HDL cholesterol level), as well as mean carotid intima-media complex thickness and high-sensitivity CRP level. Moreover, 3-month simvastatin treatment attenuated inflammation of carotid and aortic plaques. The reduction in inflammation was correlated with the increase in HDL cholesterol, but not with the decrease in LDL cholesterol. Accordingly, this non-invasive, metabolic imaging modality would aid in the risk stratification and the selection of appropriate therapy of patients at risk of atherosclerotic diseases.