[Embolic stroke of undetermined source].

About 20-40% of ischemic stroke survivors cannot be attributed to a particular pathogenetic subtype despite a thorough diagnostic evaluation (cryptogenic stroke). Most cryptogenic strokes are likely embolic. This understanding is captured by a related concept, termed embolic stroke of undetermined source (ESUS), which is defined as a nonlacunar brain infarct without proximal arterial stenosis or cardioembolic sources. These patients are generally younger, has less disabilities and more favourable prognosis. It is assumed that in this group of patients, anticoagulants may have an advantage over antiplatelet drugs as a means of secondary prevention. Specific methods of treatment and secondary prevention of ESUS has not yet been developed.