title: Heterogeneous reduction of myocardial oxidative metabolism in patients with ischemic and dilated cardiomyopathy using C-11 acetate PET.
abstract: BACKGROUND
  The 11C-acetate positron emission tomography can estimate myocardial oxidative metabolism, but previous studies have only evaluated small populations and the difference between ischemic (ICM) and idiopathic dilated cardiomyopathy (DCM) has not been fully investigated. The present aims were to evaluate global and regional myocardial oxidative metabolism in a well-characterized, large population with left ventricular (LV) dysfunction in order to clarify the metabolic differences between ICM and DCM.
  
  
  RESULTS
  Seventy-eight patients with ejection fraction (EF) < or =50% (33 ICM; 45 DCM) were compared with 14 healthy controls. Myocardial oxidative metabolism was estimated with a clearance rate constant (K(mono)) and the coefficient of variation (CV) of regional K(mono). Patients with LV dysfunction had reduced K(mono) and higher CV (p<0.05). In the comparison of oxidative alterations with clinical variables there was a weak correlation between K(mono) and LVEF (r=0.27). Although K(mono) was reduced in both ICM and DCM, CV was more pronouncedly increased in ICM (p=0.001). In multivariate analysis, the presence of left bundle branch block (LBBB) was an independent predictor of heterogeneous oxidative metabolism in DCM (R2=0.30, p<0.0001).
  
  
  CONCLUSIONS
  Global reduction of myocardial oxidative metabolism occurred in both ICM and DCM. Heterogeneous oxidative metabolism was observed in these patients, especially those with ICM. Furthermore, LBBB was the independent predictor of heterogeneous oxidative metabolism in patients with DCM.
authors.affiliation: Department of Nuclear Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Yen-Wen
authors.initials: YW
authors.lastname: Wu
authors.forename: Masanao
authors.initials: M
authors.lastname: Naya
authors.forename: Takahiro
authors.initials: T
authors.lastname: Tsukamoto
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Komatsu
authors.forename: Koichi
authors.initials: K
authors.lastname: Morita
authors.forename: Keiichiro
authors.initials: K
authors.lastname: Yoshinaga
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kuge
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tsutsui
authors.forename: Nagara
authors.initials: N
authors.lastname: Tamaki
mesh_terms: D000085:Acetates; D000368:Aged; D002037:Bundle-Branch Block / Q000000981:diagnostic imaging / Q000378:metabolism; D002250:Carbon Radioisotopes; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000378:metabolism*; D004734:Energy Metabolism; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging* / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D049268:Positron-Emission Tomography / Q000379:methods*; D011237:Predictive Value of Tests
chemical_list: D000085:Acetates; D002250:Carbon Radioisotopes; D010100:Oxygen