18F-fluoride PET/MR in cardiac amyloid: a comparison study with aortic stenosis & age- & sex-matched controls. Link to paper on Journal of Nuclear Cardiology Authors Jack P. M. Andrews, Maria Giovanni Trivieri, Russell Everett, Nicholas Spath, Gillian MacNaught, Alastair J. Moss, Mhairi K. Doris, Tania Pawade, Edwin J. R. van Beek, Christophe Lucatelli, David E. Newby, Philip Robson, Zahi A. Fayad, & Marc R. Dweck Abstract Objectives: Cardiac MR is widely used to diagnose cardiac amyloid, but cannot differentiate AL & ATTR subtypes: an important distinction given their differing treatments & prognoses. We used PET/MR imaging to quantify myocardial uptake of 18F-fluoride in ATTR & AL amyloid patients, as well as participants with aortic stenosis & age/sex-matched controls. Methods: In this prospective multicenter study, patients were recruited in Edinburgh & New York & underwent 18F-fluoride PET/MR imaging. Standardized volumes of interest were drawn in the septum & areas of late gadolinium enhancement to derive myocardial standardized uptake values (SUV) & tissue-to-background ratio (TBRMEAN) after correction for blood pool activity in the right atrium. Results: 53 patients were scanned: 18 with cardiac amyloid (10 ATTR & 8 AL), 13 controls, & 22 with aortic stenosis. No differences in myocardial TBR values were observed between participants scanned in Edinburgh & New York. Mean myocardial TBRMEAN values in ATTR amyloid (1.13 ± 0.16) were higher than controls (0.84 ± 0.11, P = .0006), aortic stenosis (0.73 ± 0.12, P < .0001), & those with AL amyloid (0.96 ± 0.08, P = .01). TBRMEAN values within areas of late gadolinium enhancement provided discrimination between patients with ATTR (1.36 ± 0.23) & all other groups (e.g., AL [1.06 ± 0.07, P = .003]). A TBRMEAN threshold >1.14 in areas of LGE demonstrated 100% sensitivity (CI 72.25 to 100%) & 100% specificity (CI 67.56 to 100%) for ATTR compared to AL amyloid (AUC 1, P = .0004). Conclusion: Quantitative 18F-fluoride PET/MR imaging can distinguish ATTR amyloid from other similar phenotypes & holds promise in improving the diagnosis of this condition. Keywords 18F-fluoride Amyloid Aortic stenosis CMR PET PET/MR Related links Link to paper on Journal of Nuclear Cardiology Dr Jack Andrews Dr Gillian MacNaught Professor Edwin van Beek Dr Christophe Lucatelli Professor David Newby Professor Marc Dweck Edinburgh Imaging facilities Heart / cardiovascular Aortic stenosis What is a PET scan? What is a PET-MR scan? Social media tags & titles Featured paper: 18F-fluoride PET/MR in cardiac amyloid: a comparison study with aortic stenosis & age- & sex-matched controls. @Jackandrews86 @MarcDweck @EdinUniCVS @JNCjournal #PETMR #AorticStenosis Publication date 05 Oct, 2020