In Vivo Imaging of Mineral Deposition in Carotid Plaque Using ^sup 18^F-Sodium Fluoride PET/CT: Correlation with Atherogenic Risk Factors

The purpose of this study was to correlate ^sup 18^F-sodium fluoride accumulation in the common carotid arteries of neuroiogically asymptomatic patients with cardiovascular risk factors and carotid calcified plaque burden. Methods: Two hundred sixty-nine oncologic patients were examined by ^sup 18^F-sodium fluoride PET/CT. Tracer accumulation in the common carotid arteries was analyzed both qualitatively and semiquantitatively by measuring the blood-pool-corrected standardized uptake value (target-to-background ratio) and comparing it with cardiovascular risk factors and calcified plaque burden. Results: ^sup 18^F-sodium fluoride uptake was observed at 141 sites in 94 (34.9%) patients. Radiotracer accumulation was colocalized with calcification in all atherosclerotic lesions. ^sup 18^F-sodium fluoride uptake was significantly associated with age (P < 0.0001), male sex (P < 0.0001), hypertension (P < 0.002), and hypercholesterolemia (P < 0.05). The presence of calcified plaque correlated significantly with these risk factors but also with diabetes (P < 0.0001), history of smoking (P = 0.03), and prior cardiovascular events (P < 0.01). There was a highly significant correlation between the presence of ^sup 18^F-sodium fluoride uptake and number of present cardiovascular risk factors (r = 0.30, P < 0.0001). Conclusion: Carotid ^sup 18^F-sodium fluoride uptake is a surrogate measure of calcifying carotid plaque, correlates with cardiovascular risk factors, and is more frequent in patients with a high-risk profile for atherothrombotic events but demonstrates a weaker correlation with risk factors than does calcified plaque burden. This study provides a rationale to conduct further prospective studies to determine whether ^sup 18^F-sodium fluoride uptake can predict vascular events, or if it may be used to monitor pharmacologic therapy. [PUBLICATION ABSTRACT]