Clinical implications of F-sodium fluoride uptake in subclinical aortic valve calcification: Its relation to coronary atherosclerosis and its predictive value.

Background: Uptake of F-sodium fluoride (F-NaF) on positron emission tomography (PET) reflects active calcification. Application of this technique in the early phase of aortic valve calcification (AVC) is of clinical interest. We investigated clinical implications of F-NaF uptake in subclinical AVC evaluated simultaneously with coronary atherosclerosis, and the utility of F-NaF uptake in predicting AVC progression.

Methods: We studied 25 patients with subclinical AVC and coronary plaques detected on computed tomography (CT) who underwent F-NaF PET/CT. AVC score, volume, mean density, and the presence of high-risk coronary plaque were evaluated on CT in each patient. Focal F-NaF uptake in AVC and in coronary plaques was quantified with the maximum tissue-to-background ratio (TBR).

Results: There were positive correlations between AVC TBR (A-TBR) and AVC parameters on CT. The 14 patients with high-risk coronary plaque had significantly higher A-TBR than those without such plaque (1.60 ± 0.18 vs 1.42 ± 0.13, respectively; P = 0.012). A-TBR positively correlated with maximum TBR of coronary plaque per patient (r = 0.55, P = 0.0043). In the 11 patients who underwent follow-up CT scan, A-TBR positively correlated with subsequent increase in AVC score (r = 0.74, P = 0.0091).

Conclusion: Our F-NaF PET- and CT-based data indicate relationships between calcification activity in subclinical AVC and characteristics of coronary atherosclerosis. F-NaF PET may provide new information regarding molecular conditions and future progression of subclinical AVC.