Embolic stroke of undetermined source:identification of patient subgroups for oral anticoagulation treatment

Background:Embolic stroke of undetermined source(ESUS),a subtype of cryptogenic stroke,was defined as acute ischemic stroke displaying an embolic or non-lacunar brain infarct pattern on imaging without significant extra or intracranial ipsilateral vessel stenosis or without an identifiable cardioembolic source such as atrial fibrillation(AF)or left ventricular thrombi(Hart et al.,2014).