title: Aortic arch atherosclerosis in ischaemic stroke of unknown origin affects prognosis.
abstract: BACKGROUND
  Cerebral infarction of unknown origin at admission accounts for half of all cerebral infarction cases in some institutions. However, the factors associated with cerebral infarction prognosis have not been sufficiently examined. Here, we investigated whether aortic arch plaques (AAPs) on transoesophageal echocardiography (TOE) were associated with the prognosis of cerebral infarction of unknown origin at admission.
  
  
  METHODS
  Of 571 patients who were hospitalised between June 2009 and September 2011, 149 (age: 67 ± 14 years; 95 men) with cerebral infarctions of unknown origin at admission underwent TOE and were enrolled in this study. We examined their clinical characteristics, the incidence of intermittent atrial fibrillation detected on 24-hour electrocardiography, and the echographic findings of the carotid artery in the hospital. A poor prognostic outcome was defined as a modified Rankin Scale score of ≥3 after 90 days.
  
  
  RESULTS
  In all, 110 patients (74%) showed good prognoses and 39 patients (26%) showed poor outcomes. A National Institutes of Health Stroke Scale score of >6 on admission [odds ratio (OR) = 6.77; 95% confidence interval (CI): 2.59-18.8; p < 0.001] and AAPs of ≥4 mm (OR = 2.75; 95% CI: 1.19-6.91; p = 0.024) showed significant associations with a poor prognosis of cerebral infarction of unknown origin at admission.
  
  
  CONCLUSIONS
  Thick AAPs could be a factor in the prediction of a poor prognosis of cerebral infarction of unknown origin at admission. The establishment of international standards for aortogenic brain embolisms is required. Future prospective studies should examine cerebral infarctions of unknown origin.
authors.affiliation: Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Arata
authors.initials: A
authors.lastname: Abe
authors.affiliation: Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Mina
authors.initials: M
authors.lastname: Harada-Abe
authors.affiliation: Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Ueda
authors.affiliation: Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Takehiro
authors.initials: T
authors.lastname: Katano
authors.affiliation: Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Nakajima
authors.affiliation: Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Kanako
authors.initials: K
authors.lastname: Muraga
authors.affiliation: Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Suda
authors.affiliation: Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Nishiyama
authors.affiliation: Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Okubo
authors.affiliation: Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Mishina
authors.affiliation: Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Ken-Ichiro
authors.initials: K
authors.lastname: Katsura
authors.affiliation: Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Katayama
keywords: Aortic arch atherosclerosis; Prognosis; Stroke of unknown origin