Abstract 12570: Aortic Valve Inflammation precedes Calcification: A longitudinal FDG-PET/CT study

Abstract

Background: Recent data shows a relationship between Aortic Valve (AV) inflammation and AV calcification (Ca). However, direct evidence linking valve inflammation to subsequent calcification is lacking in humans.

Methods: From a hospital record, we retrospectively identified patients, who are without AV stenosis or cancer and who underwent 2 PET/CT studies 1 to 5 years apart. AV inflammation was determined by measuring FDG uptake (standardized uptake value, SUV) within the AV on baseline PET. Subsequent deposition of AV Ca was determined by comparing baseline and follow-up CT scans, determined as an increase in AV Ca volume score (CVS). Patients were classified as “non-progressors” or “progressor” based on Square Root difference in CVS (using a pre-determined cut-off value of 2.5). CT and PET analysis were conducted by 2 mutually blinded laboratories.

Results: 111 patients were identified (age 60[49, 68], 50.5% male), and median [IQR] inter-scan duration 1.75 [1.17, 2.50] yrs. 23 (20.2%) patients were classified as progressors, of whom 9 (9.2%) demonstrated incident AVCa. AV SUV (mean +/- SD) was higher in progressors vs. non-progressors (2.03+/-0.52 vs.1.70+/-0.36, p = 0.02 Fig A.) as well as in patients with- vs. without- incident AV Ca (2.28+/-0.42 vs. 1.73+/-0.36, p<0.001 Fig B.). Further, AV inflammation (SUV) independently predicted subsequent calcification after adjusting for cardiovascular risk factors and baseline AV CVS [OR (95%CI):6.66(1.65 - 26.85), p = 0.008]

Conclusion: These data generate the hypothesis that inflammatatory activity is a precursor of aortic valvuar calcification. Further prospective studies are needed to conifrm this observation and the attractive propsect of non-invasive PET/CT imaging of AV as a guide for therapy and interventions in AS.