Objective: The aim of this study was to investigate the feasibility and accuracy of delayed enhancement magnetic resonance imaging (DE-MRI) for the assessment of myocardial viability in patients with myocardial infarction in comparison with (99)Tc(m)-sestamibi (MIBI) single photon emission computed tomography (SPECT) and (18)F-fluorodeoxyglucose (FDG) SPECT. Scar was defined as regionally increased MRI signal intensity 15 minutes after injection of 0.2 mmol/kg gadolinium-diethylenetriamine pentaacetic acid or reduced perfusion and glucose metabolism defined by SPECT.
Methods: A total of 34 patients with myocardial infarction (29 males, 58.0 +/- 9.8 years) were imaged with MRI and SPECT.
Results: A total of 578 segments were analyzed. DE-MRI and SPECT identified 431 and 336 viable segments respectively and SPECT also identified 30 ischemic segments. Necrotic segments identified by DE-MRI and SPECT were 147 and 212 respectively. Sensitivity and specificity of DE-MRI in identifying segments with matched flow/metabolism defects (scar tissues) was 61.3% and 95.4%, respectively. Quantitatively assessed relative MRI infarct area correlated well with SPECT infarct size. The value of Kappa was 0.51.
Conclusion: DE-MRI provides a good tool for differentiating viable myocardium from scar tissues and the detection accuracy is comparable between DE-MRI and SPECT.