Predictive Value of 18F-Sodium Fluoride Positron Emission Tomography in Detecting High-Risk Coronary Artery Disease in Combination With Computed Tomography

Abstract

Background Application of ¹⁸F-sodium fluoride (¹⁸F-NaF) positron emission tomography ( PET ) to coronary artery disease has attracted interest. We investigated the utility of ¹⁸F-NaF uptake for predicting coronary events and evaluated the combined use of coronary computed tomography (CT) angiography ( CCTA ) and ¹⁸F-NaF PET /CT in coronary artery disease risk assessment. Methods and Results This study included patients with ≥1 coronary atherosclerotic lesion detected on CCTA who underwent ¹⁸F-NaF PET / CT . High-risk plaque on CCTA was defined as plaque with low density (<30 Hounsfield units) and high remodeling index (>1.1). Focal ¹⁸F-NaF uptake in each lesion was quantified using the maximum tissue:background ratio ( TBR _max), and maximum TBR _max per patient (M- TBR _max) was determined. Thirty-two patients having a total of 112 analyzed lesions were followed for 2 years after ¹⁸F-NaF PET / CT scan, and 11 experienced coronary events (acute coronary syndrome and/or late coronary revascularization [after 3 months]). Patients with coronary events had higher M- TBR _max than those without (1.39±0.18 versus 1.19±0.17, respectively; P=0.0034). The optimal M- TBR _max cutoff to predict coronary events was 1.28 (area under curve: 0.79). Patients with M- TBR _max ≥1.28 had a higher risk of earlier coronary events than those with lower M- TBR _max ( P=0.0062 by log-rank test). In patient-based (n=41) and lesion-based (n=143) analyses of CCTA findings that predicted higher coronary ¹⁸F-NaF uptake, the presence of high-risk plaque was a significant predictor of both M- TBR _max ≥1.28 and TBR _max ≥1.28. Conclusions ¹⁸F-NaF PET / CT has the potential to detect high-risk coronary artery disease and individual coronary lesions and to predict future coronary events when combined with CCTA . Clinical Trial Registration URL : www.umin.ac.jp . Unique identifier: UMIN 000013735.

Keywords: coronary artery disease; coronary atherosclerosis; coronary computed tomography angiography; coronary event; positron emission tomography; sodium fluoride.