We describe the use of cardiac magnetic resonance imaging (CMRI) to determine myocardial viability and subsequently clinical prognosis in a patient with in utero septal myocardial infarction (MI) and dilated cardiomyopathy. MI is most commonly associated with congenital heart disease. These lesions include aortic atresia and stenosis, interrupted aortic arch, hypoplastic left ventricle (LV), and total anomalous pulmonary venous return (TAPVR). Within the last decade, it has been clearly established that systolic dysfunction is not always a definitive status after MI. In the presence of residual viable myocardium and an adequate myocardial perfusion, contractility might normalize-this process being related to a remarkable prognostic benefit. Until the use of CMRI, myocardial viability has been poorly characterized by other imaging modalities, thus making prognosis difficult to predict. Using myocardial delayed-enhancement CMRI, this patient was shown to have a dilated left ventricle with noncompaction, longitudinal midwall hyperenhancement consistent with nonviable tissue, and severely diminished left ventricular function. In conclusion, CMRI is the only imaging modality that can define anatomy, function, and tissue characterization simultaneously. In the future, CMRI could circumvent the need for more invasive diagnostic procedures in determining the cause and prognosis of patients with dilated cardiomyopathy and myocardial infarction.