title: Use of resting myocardial 18F-FDG imaging in the detection of unstable angina.
abstract: OBJECTIVE
  Increased myocardial glucose metabolism occurs with the onset of myocardial ischemia and may persist even after the restoration of blood flow, termed as 'ischemic memory'. Previous studies have demonstrated that 18F-fluorodeoxyglucose (18F-FDG) is a sensitive marker of myocardial ischemia and may have potential utility in diagnosing unstable angina (UA). This study aimed to explore the value of F-FDG PET/CT in diagnosing UA.
  
  
  METHODS
  Thirty-four patients (17 male patients; mean age, 59 ± 6 years) with suspected UA were prospectively recruited. Resting myocardial F-FDG PET/CT imaging was performed 21 ± 9 h (2-46 h) after the latest onset of angina pectoris. Resting or exercise myocardial perfusion imaging (MPI) and coronary angiography were performed. 'Focal' or 'focal on diffuse' myocardial F-FDG uptake was defined as abnormal, whereas other patterns of myocardial uptake, including 'focal' uptake on the basal segments, were considered as normal. The final diagnosis of UA was based on a comprehensive analysis of ECG, MPI, and coronary angiography.
  
  
  RESULTS
  Of the 21 patients with a final diagnosis of UA, 18 had increased 18F-FDG uptake (sensitivity 85.7%), whereas, of the 13 patients without UA, only one had abnormal 18F-FDG uptake (specificity 92.3%). The sensitivity of resting 18F-FDG imaging was higher than that of resting MPI (85.7 vs. 52.4%, P=0.016). Moreover, six UA patients with only exercise-induced ischemia showed abnormal F-FDG uptake at rest.
  
  
  CONCLUSIONS
  This pilot study demonstrated that resting 18F-FDG PET/CT imaging is an accurate and sensitive technique for the identification of UA.
authors.affiliation: aState Key Laboratory of Cardiovascular Disease, Department of Cardiology, Cardiovascular Institute, Fuwai Hospital and National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College bDepartment of Nuclear Medicine, Cardiovascular Institute, Fuwai Hospital and National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College cDepartment of Cardiology dDepartment of Nuclear Medicine, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
authors.forename: Ke-Fei
authors.initials: KF
authors.lastname: Dou
authors.forename: Bo-Qia
authors.initials: BQ
authors.lastname: Xie
authors.forename: Xiao-Jin
authors.initials: XJ
authors.lastname: Gao
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Yue-Jin
authors.initials: YJ
authors.lastname: Yang
authors.forename: Zuo-Xiang
authors.initials: ZX
authors.lastname: He
authors.forename: Min-Fu
authors.initials: MF
authors.lastname: Yang
mesh_terms: D000789:Angina, Unstable / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000503:physiopathology; D001692:Biological Transport; D015331:Cohort Studies; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009206:Myocardium / Q000378:metabolism; D049268:Positron-Emission Tomography; D014057:Tomography, X-Ray Computed
chemical_list: D019788:Fluorodeoxyglucose F18