Abstract
1615
Purpose: Technetium-labeled bone scintigraphy has been used for years for the detection of transthyretin-related cardiac amyloidosis (ATTR). However, few data exist on the utility of F-18 sodium fluoride (NaF) PET in patients with cardiac amyloidosis. The purpose of this study was to compare the uptake of NaF and technetium-labeled bone seeking tracers in patients with ATTR. METHODS: Eight patients with ATTR and 4 control subjects were examined with both NaF PET and technetium-labeled bone scintigraphy (Tc-99m pyrophosphate or Tc-99m methylene diphosphonate). Each radiotracer uptake was measured visually and semiquantitatively by calculating myocardium-to-blood pool ratios (MBR). RESULTS: Visual evaluation of NaF images showed a relative increase in myocardial uptake in 2 ATTR patients and a relative decrease in 3 ATTR patients, whereas technetium-labeled bone images showed a relative increase in myocardial uptake in all 8 ATTR patients. Three control subjects revealed a relative decrease in both NaF and technetium-labeled bone images. MBR using NaF and technetium-labeled bone images were significantly higher in ATTR patients than in control subjects (p=0.002 and p=0.02, respectively). In the group of ATTR patients, MBR using technetium-labeled bone images was significantly higher than that using NaF (p=0.005). CONCLUSION: Although NaF PET is feasible for imaging of ATTR, contrast is low and visual assessment may be challenging for clinical use, compared to technetium-labeled bone scintigraphy.