Recurrent left ventricular myocardial infarction: tissue characterization with cardiac magnetic resonance imaging.

Early risk stratification and timely revascularization are critical in patients with acute coronary syndrome. Those presenting with known coronary disease and/or prior myocardial infarction may pose clinical challenges in determining the occult territory when they develop recurrent acute coronary syndrome. Cardiac magnetic resonance (CMR) imaging offers an established noninvasive technique for functional assessment and emerging structural and tissue characterization techniques of left ventricular myocardial infarction. Conventional late gadolinium–enhanced imaging shows hyperenhancement equally in all temporal stages of myocardial infarction,1 and hence lacks specificity in differentiating recurrent acute myocardial infarction from long-standing chronic myocardial infarction. The detection of myocardial edema with T2-weighted turbo-spin-echo imaging in conjunction with late gadolinium–enhanced imaging has been shown to discriminate between acute and chronic myocardial infarctions.2 CMR imaging also offers tissue characterization methods for the detection of intramyocardial fat deposition, which has been shown to be prevalent in healed myocardial infarction.3 We present 2 cases of patients with a history of chronic myocardial infarction newly admitted for a second acute myocardial infarction. In the first case, the new myocardial infarction is in overlapping and adjacent myocardial segments. In the second case, the myocardial infarctions are in vastly different coronary artery territories. The clinical utility of CMR …