Medically reviewed by Dr. Kimberly Langdon Cull, M.D. on Sept. 21, 2023 Extracardiac uptake occurs in 11% of Tc-99m PYP scintigraphy patients. However, actionable findings are rare, according to a recent study. Transthyretin cardiac amyloidosis (ATTR-CA) can be diagnosed with the help of technetium-labeled bone-avid radiotracers. Technetium pyrophosphate (Tc-99m PYP) extracardiac uptake in this situation has...