OBJECTIVE: Although its role is a matter of debate, some studies described a higher prevalence of patent foramen ovale (PFO) and atrial septal aneurysm (ASA) in young stroke patients, with higher risk with PFO / ASA association (OR 4.96). The aim of this study was determine the prevalence of PFO and ASA in a cohort of cryptogenic ischemic stroke (IS) patients younger than 55 years and to follow-up after surgical or percutaneous endovascular closure (PEC). METHOD: In 21 months we identified all patients less than 55 years old with IS who were admitted to our hospital. Cryptogenic IS was considered if there is not an identifiably cause to cerebral ischemia. Transesophageal echocardiography (TEE) was performed in all patients. After interatrial septal abnormalities diagnosis, percutaneous device closure was offered to all. Patients were followed monthly and keeped with oral AAS or Clopidogrel. RESULTS: We identified 189 patients with IS and 32 were less than 55 years old (16.9%). In 29 the IS was cryptogenic. TEE was performed in all patients and some form of interatrial septal abnormality was identified in 12 (12/29 - 41.3%); 5 had a PFO and in 7 there was PFO plus ASA. Ten patients were submitted to PEC and 2 were submitted to surgical closure. In mid-term follow-up (28 months) no ischemic events occurred and 2 patients related disappearance of migraine symptoms. CONCLUSION: Our small series description is in accordance with other studies and suggests a possible relation between interatrial septal abnormalities and IS in a cohort of young patient.