title: Relationship between reverse redistribution on planar thallium scintigraphy and regional myocardial viability: a correlative PET study.
abstract: The purpose of this study was to assess myocardial metabolic activity in the area of reverse redistribution and determine the prognostic value of reverse redistribution and PET imaging. Reverse redistribution is thought to be a manifestation of reperfusion therapy and associated with a favorable clinical outcome. Preliminary observations from the Thrombolysis and Myocardial Infarction (TIMI) trial suggest that reverse redistribution is associated with higher incidence of future cardiac events.
  
  
  METHODS
  Thirty-two patients with chronic coronary artery disease and reverse redistribution on planar thallium scintigraphy had PET 13NH3/18FDG imaging. Radionuclide angiocardiography was performed in 23 patients.
  
  
  RESULTS
  Fifty segments showed reverse redistribution on planar thallium images; 19 segments had normal 13NH3 and 18FDG uptake and 17 were ischemic by PET criteria. Thus, a total of 72% (36 of 50) of reverse redistribution segments were PET viable. Sixty-one percent of segments with abnormal regional wall motion and reverse redistribution were PET scar. On follow-up, 31% (10/32) had a cardiac event (nine unstable angina and one myocardial infarction). Fifty percent of patients (5/10) with cardiac events had severe reverse redistribution and PET viability versus 9% (2/22) without cardiac events (p = 0.01).
  
  
  CONCLUSIONS
  The majority of thallium reverse redistribution segments was PET viable as judged by 18FDG uptake. Viability in areas of reverse redistribution is not inferred by regional wall motion analysis. Regional PET viability identifies patients with reverse redistribution with a higher likelihood of future cardiovascular events. PET viability assessment may be helpful with the impact of reverse redistribution on planar thallium scintigraphy.
authors: Department of Radiology, Yale University School of Medicine, New Haven, Connecticut.
authors: R
authors: R
authors: Soufer
authors: H M
authors: HM
authors: Dey
authors: A J
authors: AJ
authors: Lawson
authors: F J
authors: FJ
authors: Wackers
authors: B L
authors: BL
authors: Zaret
mesh_terms: D000368:Aged; D000641:Ammonia; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D003847:Deoxyglucose / Q000031:analogs & derivatives; D005080:Exercise Test; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006321:Heart / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D006801:Humans; D008297:Male; D009200:Myocardial Contraction; D009206:Myocardium / Q000378:metabolism; D009590:Nitrogen Radioisotopes; D013794:Thallium Radioisotopes; D014055:Tomography, Emission-Computed
chemical_list: D005462:Fluorine Radioisotopes; D009590:Nitrogen Radioisotopes; D013794:Thallium Radioisotopes; D019788:Fluorodeoxyglucose F18; D000641:Ammonia; D003847:Deoxyglucose