Population-Based Study of the Relationship Between Patent Foramen Ovale and Cerebrovascular Ischemic Events

Patent foramen ovale is not a risk factor for cryptogenic ischemic stroke or transient ischemic attack in the general population. The PFO's importance in the genesis of cryptogenic CIE may have been overestimated in previous studies because of selective referral of cases and underascertainment of PFO among comparison groups of patients referred for echocardiography for clinical indications other than cryptogenic CIE.