RT Journal Article
SR Electronic
T1 3 SPECT/CT quantification of DPD scintigraphy in cardiac amyloid
JF Heart
JO Heart
FD BMJ Publishing Group Ltd and British Cardiovascular Society
SP A16
OP A16
DO 10.1136/heartjnl-2018-BCVI.44
VO 104
IS Suppl 5
A1 PR Scully
A1 E Morris
A1 M Burniston
A1 TA Treibel
A1 M Jerrum
A1 K Bedford
A1 H Queenan
A1 N Hartman
A1 M Mullen
A1 M Ozkor
A1 S Kennon
A1 J Newton
A1 N Sabharwal
A1 A Kelion
A1 PM Elliott
A1 JC Moon
A1 PN Hawkins
A1 LJ Menezes
YR 2018
UL http://heart.bmj.com/content/104/Suppl_5/A16.2.abstract
AB Introduction 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) scintigraphy offers a sensitive, non-invasive test for cardiac transthyretin amyloid. The Perugini grading system relies on a visual score of the planar image – from grade 0 (negative) to 3 (strongly positive). SPECT allows the 3D visualisation of radioactivity within the body. SPECT/CT quantification may improve diagnostic accuracy and offer a means of measuring amyloid burden.Methods The software algorithm (Hermes Medical) converts recorded counts per voxel into activity per unit volume, enabling quantitative reconstructions and display of standardised uptake values (SUV). Volumes of interest were placed over the heart, adjacent vertebra, paraspinal muscle and liver and peak SUV (SUVpeak) recorded. P-values were calculated using a one-way ANOVA.Results We identified 32 patients (aged 82±9 years, 59% male), with a range of DPD results (10 grade 0, 6 grade 1, 12 grade 2, 4 grade 3). Cardiac SUVpeak increased from Perugini grade 0 to 2, but plateaued at 3 (1.39±0.47 vs 3.82±1.66 vs 12.89±4.39 vs 10.79±1.12; p<0.001).Vertebral SUVpeak decreased from Perugini grade 0 to 3 (11.75±3.79 vs 9.60±2.28 vs 8.34±2.25 vs 5.85±1.53; p<0.006). Paraspinal muscle SUVpeak increased from Perugini grade 0 to 3 (0.50±0.13 vs 0.57±0.13 vs 0.76±0.27 vs 1.29±0.24; p<0.001). Liver SUVpeak did not vary between grades (p=0.952). On ROC analysis, a cardiac SUVpeak of 2.3 diagnosed amyloidosis with 95% sensitivity and 90% specificity.Conclusion SPECT/CT quantification in DPD scintigraphy has diagnostic and discriminatory power. Competition for tracer between skeletal muscle and the heart in grade 3 cases may confound quantification of cardiac amyloid burden.