BACKGROUND: METHODS AND RESULTS: Forty-one subjects underwent vascular PET/computed tomography imaging with FDG. All had either vascular disease or multiple risk factors. Forty subjects underwent carotid imaging, 27 subjects underwent aortic, 24 subjects iliac, and 13 subjects femoral imaging. Thirty-three subjects had a panel of biomarkers analyzed. We found strong associations between FDG uptake in neighboring arteries (left versus right carotid, r=0.91, P<0.001; ascending aorta versus aortic arch, r=0.88, P<0.001). Calcification and inflammation rarely overlapped within arteries (carotid artery FDG uptake versus calcium score, r=-0.42, P=0.03). Carotid artery FDG uptake was greater in those with a history of coronary artery disease (target-to- BACKGROUND: <0.01) and in males versus females (target-to- BACKGROUND: <0.05). Similar findings were also noted in the aorta and iliac arteries. Subjects with the highest levels of FDG uptake also had the greatest concentrations of inflammatory biomarkers (descending aorta target-to- BACKGROUND: =0.53, P=0.01; carotid target-to- BACKGROUND: CONCLUSIONS: This study shows that FDG PET imaging can increase our knowledge of how atherosclerotic plaque inflammation relates to calcification, serum biomarkers, and vascular risk factors. Plaque inflammation and calcification rarely overlap, supporting the theory that calcification represents a late, burnt-out stage of atherosclerosis. Inflammation in one arterial territory is associated with inflammation elsewhere, and the degree of local arterial inflammation is reflected in the blood levels of several circulating biomarkers. We suggest that FDG PET imaging could be used as a surrogate marker of both atherosclerotic disease activity and drug effectiveness. Prospective, event-driven studies are now underway to determine the role of this technique in clinical risk prediction.
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