Quantitative analysis of myocardial glucose utilization in patients with left ventricular dysfunction by means of 18F-FDG dynamic positron tomography and three-compartment analysis.
OBJECTIVE
Myocardial glucose utilization (MGU) is altered in various heart diseases. The aim of this study was to quantitatively assess regional myocardial glucose utilization in patients with left ventricular (LV) dysfunction by dynamic( 18)F-fluorodeoxyglucose positron emission tomography (FDG PET).


METHODS
A total of 18 subjects were studied, including ten with LV dysfunction (seven with idiopathic dilated cardiomyopathy and three with aortic regurgitation; NYHA II in 8 and III in 2) and eight healthy normal volunteers. Patients with diabetes mellitus were excluded. A dynamic PET study was performed for 40 min following the injection of 370 MBq of FDG after 50-g glucose loading. On the basis of a three-compartment model, MGU, K1, k2, and k3 were computed on a pixel by pixel basis to generate LV myocardial parametric maps. FDG standardized uptake value (SUV) was also calculated using static images obtained 40 min after FDG injection. These metabolic values were compared with myocardial flow distribution (%Flow), LVEF, LV volumes, and LV wall thickening (WT) determined by gated myocardial single-photon emission computed tomography using QGS software in eight myocardial segments.


RESULTS
MGU correlated positively with LV volumes and negatively with LVEF. K(1) was significantly higher in the segments of the patients than in those of the normal volunteers (0.082+/-0.055 vs 0.041+/-0.017 ml min(-1) g(-1), p<0.05), although there was no difference in MGU between the groups. On the other hand, SUV, k2, and k3 did not differ significantly between the groups. Among the patients, the K1 values were significantly higher in the areas with impaired WT (%WT<17%) (0.109+/-0.063 vs 0.069+/-0.062 ml min(-1) g(-1), p<0.05) and in the areas with flow reduction (%Flow<71%) (0.112+/-0.076 vs 0.071+/-0.046 ml min(-1) g(-1), p<0.05).


CONCLUSIONS
These results indicate that glucose utilization was preserved in the patients with LV dysfunction, mainly due to an increase in glucose transport, particularly in the regions with severely impaired LV function. Thus, the quantitative assessment of myocardial glucose utilization by FDG dynamic PET may provide useful information for assessing the regional myocardial metabolic status in patients with LV dysfunction.
Morita
Koichi
K
Department of Nuclear Medicine, Hokkaido University Graduate School of Medicine, Kita-15, Nishi-7, Sapporo, 060-8638, Japan.
Katoh
Chietsugu
C
Yoshinaga
Keiichiro
K
Noriyasu
Kazuyuki
K
Mabuchi
Megumi
M
Tsukamoto
Takahiro
T
Kageyama
Hiroyuki
H
Shiga
Tohru
T
Kuge
Yuji
Y
Tamaki
Nagara
N
D000368:Aged; D001692:Biological Transport; D001786:Blood Glucose / Q000378:metabolism; D005260:Female; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000378:metabolism*; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism / Q000473:pathology*; D010477:Perfusion; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D013997:Time Factors; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging*
D001786:Blood Glucose; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D005947:Glucose