Abstract
Large artery atherosclerosis and cardioembolism are the two major subtypes of ischemic stroke. We herein describe a 75-year-old man with acute complete cerebral infarction in the typical territories of the bilateral anterior cerebral artery (ACA) and left middle cerebral artery. Brain magnetic resonance angiography showed that the right A1 segment of the ACA was affected by severe arteriosclerosis and that the right ACA other than the A1 segment was compensated by the left ACA through the anterior communicating artery. Acute cardioembolism only occluded the left anterior circulation but simultaneously blocked the right ACA due to decompensation. We presume that the bilateral cerebral infarctions were caused by chronic atherosclerosis and acute cardioembolism.