Comparison Between Myocardial Contrast Echocardiography and Single-Photon Emission Computed Tomography for Predicting Transmurality of Acute Myocardial Infarction

Contrast-enhanced cardiovascular magnetic resonance imaging (CMR) has been shown to accurately assess transmural extent of infarction, which is an excellent predictor of long-term improvement in contractile function. We assessed the relative accuracy of myocardial contrast echocardiography (MCE) and single-photon emission computed tomography (SPECT) to predict transmural extent of infarction after acute myocardial infarction. MCE, SPECT, and CMR were performed in 40 patients with acute myocardial infarction 7 to 10 days after thrombolysis. CMR was used to divide the transmural extent of infarction into 5 groups: 0%, 1% to 25%, 26% to 50%, 51% to 75%, and 76% to 100% in dysfunctional segments. MCE and SPECT were compared with assessment grades of transmural extent of infarction. There was a significant relation (p <0.0001) between decreasing contrast intensity as assessed qualitatively by MCE and increasing transmural extent of infarction on CMR as was the case for SPECT. The accuracy of MCE (77%) to predict >50% transmural extent of infarction (nonviable myocardium) was significantly (p = 0.02) superior to that of SPECT (70%). Absence of uptake on MCE and SPECT virtually ruled out ≤50% of the transmural extent of infarction (negative predictive values 93% and 89%, respectively). MCE was significantly more sensitive than SPECT in differentiating between ≤25% and >25% transmural extent of infarction (84% vs 76%, p = 0.03). MCE and SPECT correlate well with the transmural extent of infarction. However, MCE is significantly more accurate in predicting >50% of the transmural extent of infarction and more sensitive in identifying ≤25% of the transmural extent of infarction than SPECT.