In patients with left ventricular systolic dysfunction, the primary diagnostic issue is to differentiate the underlying cause whether related to coronary artery disease or dilated cardiomyopathy, for which coronary angiography was often used. Delayed enhancement-magnetic resonance imaging (DE-MRI) is a valuable technique to identify myocardial tissue characteristics through retention of gadolinium in areas with reduced density of viable myocytes so appear enhancing (bright). Our study included 34 patients with left ventricular systolic dysfunction (ejection fraction less than 40% by echocardiography). All of them were submitted to DE-MRI and coronary angiography. 15 patients (44%) showed infarct pattern of DE (presumed ischemic cardiomyopathy) while 19 patients (56%) showed no DE or non-infarct pattern of DE (presumed dilated cardiomyopathy) with good correlation with the results of coronary angiography. Thus, DE-MRI could be considered as an effective non-invasive tool to differentiate dilated from ischemic cardiomyopathy.