RT Journal Article
SR Electronic
T1 117 Optimisation and Reproducibility of 18F-Fluoride Positron Emission Tomography and Computed Tomography in Patients with Aortic Stenosis
JF Heart
JO Heart
FD BMJ Publishing Group Ltd and British Cardiovascular Society
SP A82
OP A82
DO 10.1136/heartjnl-2016-309890.117
VO 102
IS Suppl 6
A1 Tania Pawade
A1 Timothy Cartlidge
A1 David Newby
A1 Dweck Marc
YR 2016
UL http://heart.bmj.com/content/102/Suppl_6/A82.1.abstract
AB Background 18F-Fluoride positron emission tomography (PET) and computed tomography (CT) can measure disease activity and progression in aortic stenosis. We aimed to optimise imaging methodology, analysis and scan-rescan reproducibility.Methods Fifteen patients with aortic stenosis underwent 18F-fluoride PET-CT twice within 1 month. We compared non-gated PET and non-contrast CT, with a modified approach that incorporated contrast CT and ECG-gated PET. We explored a range of image analysis techniques including estimation of blood pool activity at differing vascular sites and a most-diseased segment (MDS) approach.Results Contrast-enhanced ECG-gated PET-CT provided superior spatial localisation of 18F-fluoride uptake that permitted localisation to individual valve leaflets (Figure). Scan-rescan reproducibility was markedly improved using enhanced analysis techniques leading to a reduction in variability from 25% to <10% (tissue-to-background MDS: mean value 1.55, difference 0.05, limits of agreement -0·10 to 0·20).Abstract 117 Figure 1 Blood pool correction was performed by sampling from the right atrium instedad of the brachio-cephalic vein. 2. The most diseased segment method was used to quantify the PET signal within 2 hottest slices rather than the whole valve/ 3. Contrase CT fused with ECG-gated PET gacilitated better localization to leaflets compared to the original approach 4. Bland-Altmanplots emonstrated superior sacn-rescan reproducibility for the modified technique (2b) compared to the previous approach (2a)Conclusion Optimised 18F-fluoride PET-CT provides excellent spatial resolution and scan-rescan reproducibility. It holds major promise as a marker of disease activity in aortic stenosis and has major potential as a biomarker end-point of trials of novel therapies in aortic stenosis.