Reduced 123I-BMIPP uptake implies decreased myocardial flow reserve in patients with chronic stable angina.
OBJECTIVE
Long-chain fatty acid (LCFA) is the main energy source for normal myocardium at rest, but in ischemic myocardium, the main energy substrate shifts from LCFA to glucose. 123I-BMIPP is a radiolabeled LCFA analog. In chronic stable angina without previous infarction, we suppose that reduced 123I-BMIPP uptake is related to the substrate shift in myocardium with decreased myocardial flow reserve (MFR). The purpose of this study was to relate 123I-BMIPP uptake to rest myocardial blood flow (MBF), hyperemic MBF, and MFR assessed with 15O-water positron emission tomography (PET).


METHODS
We enrolled 21 patients with chronic stable angina without previous infarction, all of whom underwent 123I-BMIPP single-photon emission computed tomography (SPECT) and 15O-water PET. The left ventricle was divided into 13 segments. In each segment, rest MBF and hyperemic MBF were measured by PET. 123I-BMIPP uptake was evaluated as follows: score 0=normal, 1=slightly decreased uptake, 2=moderately decreased uptake, 3=severely decreased uptake, and 4=complete defect. 123I-BMIPP uptake was compared with rest MBF, hyperemic MBF, and MFR.


RESULTS
The numbers of segments with 123I-BMIPP scores 0, 1, 2, 3, and 4 were 178, 40, 25, 24, and 0, respectively. The rest MBFs for scores 0, 1, 2, and 3 were 0.93+/-0.25, 0.86+/-0.21, 0.97+/-0.30, and 0.99+/-0.37 ml/min/g, respectively. The hyperemic MBFs for scores 0, 1, 2, and 3 were 2.76+/-1.29, 1.84+/-0.74, 1.37+/-0.39, and 1.08+/-0.40 ml/min/g, respectively. The MFRs for scores 0, 1, 2, and 3 were 3.01+/-1.38, 2.20+/-0.95, 1.44+/-0.22, and 1.10+/-0.26, respectively. As 123I-BMIPP uptake declined, hyperemic MBF and MFR decreased.


CONCLUSIONS
In chronic stable angina without previous infarction, reduced 123I-BMIPP uptake implies decreased MFR.
Kageyama
Hiroyuki
H
Department of Nuclear Medicine, Hokkaido University Graduate School of Medicine, Kita-15, Nishi-7, Kita-ku, Sapporo 060-8638, Japan.
Morita
Koichi
K
Katoh
Chietsugu
C
Tsukamoto
Takahiro
T
Noriyasu
Kazuyuki
K
Mabuchi
Megumi
M
Naya
Masanao
M
Kawai
Yuko
Y
Tamaki
Nagara
N
D000328:Adult; D000368:Aged; D000789:Angina, Unstable / Q000000981:diagnostic imaging* / Q000209:etiology / Q000378:metabolism*; D003324:Coronary Artery Disease / Q000150:complications / Q000000981:diagnostic imaging* / Q000378:metabolism; D003326:Coronary Circulation; D005227:Fatty Acids / Q000378:metabolism* / Q000493:pharmacokinetics; D005260:Female; D006801:Humans; D007462:Iodobenzenes / Q000493:pharmacokinetics*; D008297:Male; D008875:Middle Aged; D010104:Oxygen Radioisotopes / Q000493:pharmacokinetics; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors
D005227:Fatty Acids; D007462:Iodobenzenes; D010104:Oxygen Radioisotopes; D019275:Radiopharmaceuticals; C049338:iodofiltic acid