Relationship between Late Gadolinium Enhancement Extent in Cardiac Magnetic Resonance Imaging and Severity of Coronary Artery Disease in Old Myocardial Infarction

Background: Contrast-enhanced cardiac magnetic resonance imaging (CMR) is an accurate imaging modality for the noninvasive evaluation of myocardial infarction (MI). We sought to assess the relationship between the severity of coronary involvement and the extent and pattern of myocardial scars in CMR of patients with a history of remote MI. Methods: The CMR of 60 patients with a history of remote ST-elevation or non-ST elevation MI who were candidated for selective coronary angiography and referred for CMR for an evaluation of myocardial viability was reviewed and compared with selective coronary angiographic findings. Results: Among the 60 patients with a history of old MI, 78.3% were male and the mean (SD) of age was 61.2±11.5 years. There was no association between the severity of coronary stenosis in each territory and the presence of myocardial scar detected by the late gadolinium enhancement of CMR. (P values for all the territories of the 3 vessels were >0.05.) There was a significant association between coronary artery run-off and the presence of late gadolinium enhancement in CMR. (P values for the left anterior descending, left circumflex artery, and right coronary artery were 0.002, <0.001, and <0.001, respectively.) We found a significant relationship between the pattern of the scars in terms of being transmural or non-transmural and the severity of coronary artery stenosis (P<0.001), and the pattern of the scars was not associated with coronary artery run-off (P=0.2). Conclusions: The results of this study support the hypothesis that the time window for revascularization will be increased in the presence of an antegrade coronary flow in the jeopardized myocardium and that it could limit infarct progression and result in a subsequent lesser extent of myocardial scar.