Etiologic investigation of ischemic stroke in young adults

# {#article-title-2} To the Editor: We read with interest the article by Larrue et al.1 We recently assessed the impact of newer stroke classification systems on stroke subtypes.2 We also agree with the conclusion regarding the contribution of atrial septal abnormalities to stroke in younger people. Despite the thorough cardiac investigation, Larrue et al. report a relatively low proportion of patients with unexplained stroke with patent foramen ovale (PFO). Of 160 cases investigated, 67 (41.2%) had a PFO (24 isolated, 43 with an atrial septal aneurysm [ASA]). In our institution, of those with …