A 77-year-old woman with chest pain was admitted to our hospital for evaluation and treatment. Electrocardiography showed T-wave inversion in the I, aVL and V2-V6 leads. Emergency coronary angiography showed 75% stenosis in the left anterior descending artery. Left ventriculography demonstrated akinesis of the left ventricular apical region. Iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid radioactive isotope imaging showed an uptake defect in the apical region during the acute phase, but the defect disappeared 1 month later. Cine cardiac magnetic resonance (CMR) in the acute phase showed apical akinesis and hyperkinesis of the mid region, as observed by left ventriculography. Contrast magnetic resonance imaging with gadolinium showed no delayed hyperenhancement. One month later, cine CMR showed disappearance of the abnormal wall motion and contrast magnetic resonance imaging demonstrated no delayed hyperenhancement. CMR is useful to monitor changes in wall motion and wall thickening in the stunned myocardium.