title: Strokes after cardioversion of atrial fibrillation--The FibStroke study.
abstract: BACKGROUND
  Cardioversion of atrial fibrillation (AF) is associated with an increased risk for stroke. We identified all cardioversions during the 30 days preceding stroke or transient ischemic attack (TIA) in patients with a previously diagnosed AF, and sought to assess the characteristics of cardioversions leading to stroke or TIA.
  
  
  METHODS
  FibStroke is a cross-sectional observational multicenter registry that included AF patients with an ischemic stroke or intracranial bleed identified from a discharge registry of four Finnish hospitals. In total 3677 consecutive AF patients suffered 3252 strokes and 956 TIA episodes during 2003–2012. This pre-specified analysis focused on the 1644 events that occurred to patients with paroxysmal or persistent AF at the time of stroke/TIA.
  
  
  RESULTS
  A total of 78 strokes and 22 TIA episodes were preceded by a cardioversion. Post-cardioversion strokes accounted for 6.4% of strokes in patients with paroxysmal/persistent AF. Of the 100 cardioversions leading to an ischemic event, 77 were acute and 23 were elective, 63 events occurred in patients not using anticoagulation, and 5 patients had periprocedural INR < 2. Importantly, 21 patients were in low risk of stroke, i.e. CHA2DS2-VASc score < 2. The median delay from cardioversion to event was 2 days. All nine patients who after an unsuccessful cardioversion developed a stroke had a spontaneous cardioversion prior to stroke.
  
  
  CONCLUSIONS
  Every sixteenth stroke of patients with paroxysmal/persistent AF is preceded by a cardioversion. Most post-cardioversion strokes occur in patients not using oral anticoagulation before cardioversion of acute AF.
authors.affiliation: Heart Center, Turku University Hospital, University of Turku, Hämeentie 11, PO Box 52, 20521 Turku, Finland. Electronic address: ajpalo@utu.fi.
authors.forename: Antti
authors.initials: A
authors.lastname: Palomäki
authors.affiliation: Department of Medicine, Keski-Suomi Central Hospital, Keskussairaalantie 19, 40620 Jyväskylä, Finland. Electronic address: pirjo.mustonen@ksshp.fi.
authors.forename: Pirjo
authors.initials: P
authors.lastname: Mustonen
authors.affiliation: Heart Center, Kuopio University Hospital, Puijonlaaksontie 2, 70210 Kuopio, Finland. Electronic address: juha.hartikainen@kuh.fi.
authors.forename: Juha E K
authors.initials: JE
authors.lastname: Hartikainen
authors.affiliation: Department of Medicine, Turku University Hospital,University of Turku, Hämeentie 11, PO Box 52, 20521 Turku, Finland. Electronic address: ilpo.nuotio@tyks.fi.
authors.forename: Ilpo
authors.initials: I
authors.lastname: Nuotio
authors.affiliation: Heart Center, Turku University Hospital, University of Turku, Hämeentie 11, PO Box 52, 20521 Turku, Finland. Electronic address: tuoski@utu.fi.
authors.forename: Tuomas
authors.initials: T
authors.lastname: Kiviniemi
authors.affiliation: Heart Center, Satakunta Central Hospital, Sairaalantie 3, 28500 Pori, Finland. Electronic address: antti.ylitalo@dnainternet.net.
authors.forename: Antti
authors.initials: A
authors.lastname: Ylitalo
authors.affiliation: NeuroCenter, Neurology, Kuopio University Hospital, Puijonlaaksontie 2, 70210 Kuopio, Finland. Electronic address: paivi.hartikainen@kuh.fi.
authors.forename: Päivi
authors.initials: P
authors.lastname: Hartikainen
authors.affiliation: Department of Medicine, Keski-Suomi Central Hospital, Keskussairaalantie 19, 40620 Jyväskylä, Finland. Electronic address: heidi.lehtola@ksshp.fi.
authors.forename: Heidi
authors.initials: H
authors.lastname: Lehtola
authors.affiliation: Heart Center, Kuopio University Hospital, Puijonlaaksontie 2, 70210 Kuopio, Finland. Electronic address: riho.luite@kuh.fi.
authors.forename: Riho
authors.initials: R
authors.lastname: Luite
authors.affiliation: Heart Center, Turku University Hospital, University of Turku, Hämeentie 11, PO Box 52, 20521 Turku, Finland. Electronic address: juhani.airaksinen@tyks.fi.
authors.forename: K E Juhani
authors.initials: KE
authors.lastname: Airaksinen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000592:standards / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D003430:Cross-Sectional Studies; D004554:Electric Countershock / Q000379:methods; D004562:Electrocardiography / Q000379:methods; D005260:Female; D006801:Humans; D002546:Ischemic Attack, Transient / Q000150:complications* / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012307:Risk Factors; D020521:Stroke / Q000000981:diagnostic imaging / Q000209:etiology*; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants
keywords: Atrial fibrillation; Cardioversion; Stroke; Transient ischemic attack