A new syndrome, first described by the Japanese, presents as acute myocardial infarction. However, by closer examination it shows extensive akinesia in the apical and mid portions of the left ventricle, in the absence of significant coronary artery stenosis. Recently this syndrome has also been recognised outside Japan. The mechanism is unclear, but diffuse impairment of coronary microcirculation may play a role in the pathogenesis. Timely diagnosis of this potential lethal condition is mandatory, as it avoids the unnecessary risk of thrombolysis and allows adequate treatment to be started early. Diagnosis is also important for reassuring the patients that they have a good chance of complete recovery. We present three cases with this syndrome and discuss pathogenesis and clinical implications.