title: Diffusion-weighted imaging in stroke attributable to patent foramen ovale: significance of concomitant atrial septum aneurysm.
abstract: OBJECTIVE
  Patent foramen ovale (PFO) is an established cause of stroke in young patients without other determined etiologies (ie, cryptogenic stroke). The additional presence of atrial septum aneurysm (ASA) possibly increases stroke risk, but it remains undetermined which factors best predict thromboembolism in patients with PFO. Diffusion-weighted imaging (DWI) may help to distinguish the characteristics of cerebral embolism associated with different features of the interatrial septum in PFO stroke.
  
  
  METHODS
  In a stroke databank-based cohort study, DWI and transthoracic/transesophageal echocardiography findings were assessed in 48 consecutive patients with cryptogenic ischemic stroke associated with PFO. The number, size, and distribution of acute ischemic lesions on DWI were correlated with PFO size, degree of interatrial right-to-left shunt (RLS), and the presence of ASA.
  
  
  RESULTS
  Patients with PFO plus ASA combined more often had multiple acute DWI lesions (16 of 30, 53%) than those with PFO alone (3 of 18, 17%; P=0.01). This association remained significant after correction for PFO size, degree of RLS, and vascular risk factors in a logistic-regression analysis (P=0.04). No significant associations between DWI lesion characteristics and PFO size or degree of RLS were found.
  
  
  CONCLUSIONS
  The presence of concomitant ASA is independently associated with multiple cerebral ischemic lesions in PFO stroke, which may indicate an increased embolic risk.
authors.affiliation: Department of Neurology and Stroke Unit, University Hospital Basel, Petersgraben 4, CH-4031 Basel, Switzerland. bonatil@uhbs.ch
authors.forename: Leo H
authors.initials: LH
authors.lastname: Bonati
authors.forename: Arnheid
authors.initials: A
authors.lastname: Kessel-Schaefer
authors.forename: André Z
authors.initials: AZ
authors.lastname: Linka
authors.forename: Peter
authors.initials: P
authors.lastname: Buser
authors.forename: Stephan G
authors.initials: SG
authors.lastname: Wetzel
authors.forename: Ernst-Wilhelm
authors.initials: EW
authors.lastname: Radue
authors.forename: Philippe A
authors.initials: PA
authors.lastname: Lyrer
authors.forename: Stefan T
authors.initials: ST
authors.lastname: Engelter
mesh_terms: D000328:Adult; D002545:Brain Ischemia / Q000150:complications; D015331:Cohort Studies; D003326:Coronary Circulation; D016208:Databases, Factual; D038524:Diffusion Magnetic Resonance Imaging; D004452:Echocardiography; D017548:Echocardiography, Transesophageal; D005260:Female; D006322:Heart Aneurysm / Q000150:complications*; D006325:Heart Atria; D006344:Heart Septal Defects, Atrial / Q000150:complications* / Q000000981:diagnostic imaging; D006346:Heart Septum; D006801:Humans; D020766:Intracranial Embolism / Q000175:diagnosis / Q000209:etiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012189:Retrospective Studies; D020521:Stroke / Q000175:diagnosis* / Q000209:etiology* / Q000503:physiopathology