Detecting viable myocardium and predicting functional improvement: comparisons of positron emission tomography, rest-redistribution thallium-201 single-photon emission computed tomography (SPECT), exercise thallium-201 reinjection SPECT, I-123 BMIPP SPECT and dobutamine stress echocardiography.
BACKGROUND
Low-dose dobutamine stress echocardiography (LDDE) has become a useful and safe method for identifying hibernating or stunned myocardium and for predicting improvement in wall motion after coronary revascularization.


RESULTS
In the present study, fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET), rest-redistribution thallium-201 ((201)Tl) single-photon emission computed tomography (RR-Tl SPECT), (123)I-15-(p-iodophenyl)-3-(R,S)-methyl pentadecanoic acid (BMIPP) and LDDE were performed in 30 patients with acute myocardial infarction (AMI) at 10+/-3 days after the onset of AMI. Also, exercise (201)Tl reinjection SPECT (RI-Tl SPECT) was performed at 14+/-2 days. Follow-up echocardiography was performed 5+/-3 months later in all patients after interventional therapy for the assessment of functional recovery. Of the 390 segments analyzed by echocardiography, 110 (28%) had abnormal wall motion. There were no significant differences between RR-Tl SPECT and LDDE in sensitivity, specificity, positive predictive value and negative predictive value using the chi(2)-test; however, in akinetic segments, there was a significant difference in sensitivity. Among FDG-PET, RI-Tl SPECT, BMIPP and LDDE, there were significant differences in 3 variables. In akinetic segments, LDDE is superior to RR-Tl SPECT in sensitivity and to FDG-PET in specificity. In hypokinetic segments, LDDE is superior to RI-Tl SPECT and BMIPP in sensitivity, and to FDG-PET and BMIPP in specificity.


CONCLUSIONS
LDDE could detect functional recovery of viable myocardium in the early period of AMI and can be performed easily and safely.
First Department of Internal Medicine, Osaka City University Medical School, Japan.
Tomoko
T
Tani
Masakazu
M
Teragaki
Hiroyuki
H
Watanabe
Takashi
T
Muro
Hiroyuki
H
Yamagishi
Kaname
K
Akioka
Minoru
M
Yoshiyama
Kazuhide
K
Takeuchi
Junichi
J
Yoshikawa
D000368:Aged; D002316:Cardiotonic Agents / Q000008:administration & dosage*; D004280:Dobutamine / Q000008:administration & dosage*; D025401:Echocardiography, Stress / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017682:Myocardial Stunning / Q000175:diagnosis*; D049268:Positron-Emission Tomography / Q000379:methods*; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
D002316:Cardiotonic Agents; D013794:Thallium Radioisotopes; D004280:Dobutamine