title: Hibernating myocardium versus scar: severity of irreversible decreased myocardial perfusion in prediction of tissue viability.
abstract: OBJECTIVE
  To determine whether quantitation of the relative severity of decreased perfusion in irreversible defects on myocardial perfusion images enables differentiation of viable hibernating myocardium from scar.
  
  
  METHODS
  In 145 patients with previous myocardial infarction, 1,252 regions with irreversible defects proved by means of rubidium-82 rest-stress imaging were analyzed for relative severity (percentage decrease in perfusion). Myocardial tissue viability was determined by means of positron emission tomography with fluorine-18 fluorodeoxyglucose (FDG).
  
  
  RESULTS
  The relative decreases in Rb-82 uptake in the 1,252 regions were categorized into nine levels of severity (30% to > or = 70%) in 381 regions of hibernating myocardium and 871 regions of scar. The values of relative decreased perfusion in the irreversible defects alone did not enable differentiation of hibernating myocardium and scar (P = .61).
  
  
  CONCLUSIONS
  The results show no relationship between the relative severity of irreversible perfusion defects and the ability to distinguish between hibernating myocardium and scar.
authors.affiliation: Department of Nuclear Medicine, Cleveland Clinic Foundation, OH 44195-5074.
authors.forename: R T
authors.initials: RT
authors.lastname: Go
authors.forename: W J
authors.initials: WJ
authors.lastname: MacIntyre
authors.forename: G B
authors.initials: GB
authors.lastname: Saha
authors.forename: S A
authors.initials: SA
authors.lastname: Cook
authors.forename: D R
authors.initials: DR
authors.lastname: Neumann
authors.forename: E Q
authors.initials: EQ
authors.lastname: Chen
authors.forename: D A
authors.initials: DA
authors.lastname: Underwood
authors.forename: T
authors.initials: T
authors.lastname: Kaczur
mesh_terms: D002470:Cell Survival; D003847:Deoxyglucose / Q000031:analogs & derivatives; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D009203:Myocardial Infarction / Q000000981:diagnostic imaging*; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging; D009206:Myocardium / Q000473:pathology*; D011877:Radionuclide Imaging; D012414:Rubidium Radioisotopes
chemical_list: D005462:Fluorine Radioisotopes; D012414:Rubidium Radioisotopes; D019788:Fluorodeoxyglucose F18; D003847:Deoxyglucose