Detection of doxorubicin cardiotoxicity by using iodine-123 BMIPP early dynamic SPECT: quantitative evaluation of early abnormality of fatty acid metabolism with the Rutland method.
BACKGROUND
To evaluate the possibility of predicting the development of doxorubicin-induced cardiomyopathy, we performed quantitative assessment of the early kinetics of iodine-123 beta-methyl-iodophenyl-pentadecanoic acid (I-123 BMIPP) by means of dynamic myocardial SPECT.


METHODS
Thirty-six patients with various malignancies were examined. I-123 BMIPP dynamic myocardial SPECT was performed before chemotherapy, after chemotherapy, or both. Immediately after the injection of I-123 BMIPP (111 MBq), 30-second dynamic SPECT data were acquired successively for 15 minutes. The left ventricular (LV) myocardium was divided into 8 segments in short-axial and vertical slices. By using the time-activity curve (TAC) of each myocardial segment [Mo(t)] as an output function and the TAC of the LV cavity [B(t)] as an input function, the Rutland equation, Mo(t)/B(t)= F + K Integral of(B(t)dt/B(t)), was used as a means of assessing all segments.


RESULTS
Mo(t)/B(t) showed a good linear correlation with Integral of(B(t)dt/B(t)) from 30 seconds to 4 minutes in all 456 segments. The mean K value of 8 LV segments was significantly lower after chemotherapy than before chemotherapy (0.071+/-0.019 [n = 21] vs. 0.095+/-0.025 [n = 36], P<.001). In 21 patients in whom dynamic SPECT was performed both before and after chemotherapy, the mean K values of left ventricle showed a significant decrease, from 0.101+/-0.024 to 0.071 +/-0.019 (P<.0001). The fractional change in the value of K after chemotherapy showed a significant linear correlation with the administered dose of doxorubicin (r = 0.648, P<.002).


CONCLUSIONS
I-123 BMIPP dynamic myocardial SPECT may be clinically useful, because it permits the early detection of doxorubicin-induced cardiomyopathy.
Saito
K
K
Department of Internal Medicine, Yamamoto General Hospital, Kuwana, Mie, Japan. k1saito@carrot.ocn.ne.jp
Takeda
K
K
Okamoto
S
S
Okamoto
R
R
Makino
K
K
Tameda
Y
Y
Nomura
Y
Y
Maeda
H
H
Ichihara
T
T
Nakano
T
T
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000009:adverse effects*; D009202:Cardiomyopathies / Q000139:chemically induced* / Q000000981:diagnostic imaging / Q000378:metabolism; D004317:Doxorubicin / Q000009:adverse effects*; D004452:Echocardiography; D005227:Fatty Acids / Q000378:metabolism*; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging* / Q000187:drug effects; D006801:Humans; D007457:Iodine Radioisotopes; D007462:Iodobenzenes; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism*; D019275:Radiopharmaceuticals; D015899:Tomography, Emission-Computed, Single-Photon
D000970:Antineoplastic Agents; D005227:Fatty Acids; D007457:Iodine Radioisotopes; D007462:Iodobenzenes; D019275:Radiopharmaceuticals; C049338:iodofiltic acid; D004317:Doxorubicin