In Vivo Imaging of Macrophage Activity in the Coronary Arteries Using 68Ga-DOTATATE PET/CT: Correlation with Coronary Calcium Burden and Risk Factors

We measured the uptake of the somatostatin receptor ligand Ga-68-[1,4,7,10-tetraazacyclododecane-N,N',N '',N '''-tetraacetic acid]-D-Phe(1),Tyr(3)-octreotate (DOTATATE) in the left anterior descending coronary artery (LAD) in association with calcified plaques (CPs) and cardiovascular risk factors. Methods: Seventy consecutive tumor patients were examined by whole-body Ga-68-DOTATATE contrast-enhanced PET/CT. Blood-pool-corrected standardized uptake value (target-to-background ratio) was measured in the LAD, and CT images were used to detect CP. Cardiovascular risk factors and history of prior cardiovascular events were recorded. Results: Ga-68-DOTATATE uptake was detectable in the LAD of all patients. Target-to-background ratio in the LAD correlated significantly with the presence of CP (R = 0.34; P < 0.01), prior vascular events (R = 0.26; P < 0.05), and male sex (R = 0.29; P < 0.05), whereas CP correlated with these parameters but also with age (R = 0.34; P < 0.01) and hypertension (R = 0.25; P < 0.05). Conclusion: In a series of oncologic patients, those with prior cardiovascular events and calcified atherosclerotic plaques showed significantly increased Ga-68-DOTATATE uptake in the LAD, suggesting a potential role of this tracer for plaque imaging in the coronary arteries.