Global quantification of pulmonary artery atherosclerosis using ¹⁸F-sodium fluoride PET/CT in at-risk subjects

The goal of this study was to assess pulmonary artery calcification in healthy controls and subjects with suspicion of stable angina pectoris through the usage of quantitative ¹⁸F-sodium fluoride positron emission tomography/computed tomography (NaF-PET/CT). We hypothesized that these 'at-risk subjects' would demonstrate increase pulmonary artery NaF uptake compared to healthy controls. Retrospectively, 15 healthy controls were compared to 15 at-risk subjects, all of whom underwent full-body NaF-PET/CT scans. The healthy controls and at-risk patients were all randomly sampled from larger datasets. The two sampled groups were male-dominated and similar in age. The global mean standard uptake value (SUVmean), the max standard uptake value (SUVmax), and the mean target-to-background ratio (TBRmean) were acquired through mapping of regions of interest (ROI's) around the pulmonary artery of the subjects. A two-tailed Mann-Whitney U test was used to determine the significance of difference between the two groups. For global SUVmean (0.79 compared to 0.58), global TBRmean (1.15 compared to 0.93), and global SUVmax (1.78 compared to 1.60), the NaF uptake was significantly higher in the at-risk patients compared to the controls (all P<0.05). NaF-PET/CT is a suitable imaging modality for quantification of molecular calcification in the pulmonary artery. Additionally, the connection between atherosclerosis and the risk factor of angina pectoris is further reinforced. We believe that future studies are needed to validate our proof-of-concept, and better confirm the clinical future of NaF-PET/CT as a tracer of atherosclerotic plaques.