Thallium-201 SPECT and low-dose dobutamine stress cine MRI for predicting functional recovery of regional myocardial contraction in patients with myocardial infarction.
OBJECTIVE
The purpose of this study was to compare the diagnostic performances of Tl-201 single photon emission computed tomography (SPECT) and dobutamine stress cine magnetic resonance imaging (MRI) for predicting functional recovery of regional myocardial contraction in patients after myocardial infarction.


METHODS
Twenty patients underwent Tl-201 SPECT and MRI 3-4 weeks after onset of myocardial infarction. Cine MR images were acquired in the resting state and during dobutamine stress. Tl-201 uptake and systolic wall thickening (SWT) on cine MRI were analyzed on short-axis images by using a 14-segment model. Follow-up cine MR images were obtained 187.1+/-33.5 days after onset.


RESULTS
The averaged Tl-201 uptake in 54 segments with impaired SWT was 47%+/-20%, being significantly lower than that in 226 segments with preserved SWT (75%+/-18%; p<0.0001). The sensitivity, specificity, and accuracy of dobutamine MRI and Tl-201 SPECT for predicting preserved SWT after 6 months were 89% vs. 80%, not significant (NS); 89% vs. 72%, p<0.01; and 89% vs. 79%, NS, respectively. In the anterior wall and apex, the sensitivity and specificity of SPECT were not significantly different from those of MRI. In the inferior wall and posterolateral wall, however, the specificity of SPECT was substantially lower than that of MRI (53% vs. 88%, p<0.001), resulting in significantly lower accuracy (75% vs. 90%, p<0.01).


CONCLUSIONS
Both SPECT and dobutamine MRI showed excellent sensitivity for predicting myocardial viability in all left ventricular segments. Decreased specificity of SPECT in the inferior and posterolateral segments resulted in lower overall specificity in comparison with dobutamine MRI.
Uemura
Shoko
S
First Department of Internal Medicine, Mie University School of Medicine, Tsu, Mie, Japan.
Sakuma
Hajime
H
Motoyasu
Munenobu
M
Ichikawa
Yasutaka
Y
Kitagawa
Kakuya
K
Tamada
Hiroya
H
Okinaka
Tsutomu
T
Isaka
Naoki
N
Takeda
Kan
K
Nakano
Takeshi
T
D000328:Adult; D000368:Aged; D002316:Cardiotonic Agents; D004280:Dobutamine; D004305:Dose-Response Relationship, Drug; D025401:Echocardiography, Stress; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology; D009203:Myocardial Infarction / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D009204:Myocardial Revascularization; D011237:Predictive Value of Tests; D020127:Recovery of Function / Q000502:physiology*; D012146:Rest / Q000502:physiology; D012680:Sensitivity and Specificity; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon; D018487:Ventricular Dysfunction, Left / Q000473:pathology / Q000503:physiopathology
D002316:Cardiotonic Agents; D013794:Thallium Radioisotopes; D004280:Dobutamine