Heterogeneous reduction of myocardial oxidative metabolism in patients with ischemic and dilated cardiomyopathy using C-11 acetate PET.
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.
Wu
Yen-Wen
YW
Department of Nuclear Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
Naya
Masanao
M
Tsukamoto
Takahiro
T
Komatsu
Hiroshi
H
Morita
Koichi
K
Yoshinaga
Keiichiro
K
Kuge
Yuji
Y
Tsutsui
Hiroyuki
H
Tamaki
Nagara
N
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
D000085:Acetates; D002250:Carbon Radioisotopes; D010100:Oxygen