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 60patients with a history of remote ST-elevation or non-ST elevation MI who were candidatedfor selective coronary angiography and referred for CMR for an evaluation ofmyocardial viability wasreviewed and compared with selective coronary angiographic findings.Results:Among the 60 patients withahistory of old MI, 78.3%were male andthe mean(SD) of age was 61.2±11.5years. There was no association between the severityof coronary stenosis in each territory andthepresence of myocardial scar detected bythelate gadolinium enhancement of CMR.(P values for all the territories of the 3 vessels were >0.05.)There wasasignificant association between coronary artery run-off and the presence of late gadolinium enhancementin CMR.(P values for the left anterior descending,left circumflex artery,and right coronary arterywere0.002, <0.001,and <0.001,respectively.)We found a significant relationship between the pattern of the scarsin terms of beingtransmural or non-transmural andtheseverity of coronary artery stenosis (P<0.001),and the pattern of the scarswas not associated with coronary artery run-off (P=0.2).Conclusions:The resultsof this study support the hypothesis that the time window for revascularization will be increased in the presence of an antegrade coronary flow in the jeopardizedmyocardium andthat itcouldlimit infarct progression and resultina subsequent lesser extent of myocardial scar.(Iranian Heart Journal 2015; 16(4): 12-18)