FDG PET Viability: Hibernating Myocardium

C. FDG PET viability study — hibernating myocardium shows preserved FDG uptake despite reduced perfusion

Hibernating myocardium refers to chronically hypoperfused but viable myocardium that shows wall motion abnormality at rest but can recover function after revascularization. On MPI, it appears as a fixed (non-reversible) perfusion defect — similar to scar. FDG PET viability imaging exploits the fact that viable myocardium switches to glucose metabolism under ischemic conditions: hibernating tissue shows a 'perfusion-metabolism mismatch' (reduced perfusion, preserved FDG uptake). Pure scar shows concordantly reduced perfusion AND reduced FDG uptake. Identifying hibernation guides the decision for revascularization.