title: Efficacy and safety of apixaban in patients after cardioversion for atrial fibrillation: insights from the ARISTOTLE Trial (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation).
abstract: OBJECTIVE
  The aim of this study was to determine the risk of major clinical and thromboembolic events after cardioversion for atrial fibrillation in subjects treated with apixaban, an oral factor Xa inhibitor, compared with warfarin.
  
  
  BACKGROUND
  In patients with atrial fibrillation, thromboembolic events may occur after cardioversion. This risk is lowered with vitamin K antagonists and dabigatran.
  
  
  METHODS
  Using data from the ARISTOTLE (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation) trial, we conducted a post-hoc analysis of patients undergoing cardioversion.
  
  
  RESULTS
  A total of 743 cardioversions were performed in 540 patients: 265 first cardioversions in patients assigned to apixaban and 275 in those assigned to warfarin. The mean time to the first cardioversion for patients assigned to warfarin and apixaban was 243 ± 231 days and 251 ± 248 days, respectively; 75% of the cardioversions occurred by 1 year. Baseline characteristics were similar between groups. In patients undergoing cardioversion, no stroke or systemic emboli occurred in the 30-day follow-up period. Myocardial infarction occurred in 1 patient (0.2%) receiving warfarin and 1 patient receiving apixaban (0.3%). Major bleeding occurred in 1 patient (0.2%) receiving warfarin and 1 patient receiving apixaban (0.3%). Death occurred in 2 patients (0.5%) receiving warfarin and 2 patients receiving apixaban (0.6%).
  
  
  CONCLUSIONS
  Major cardiovascular events after cardioversion of atrial fibrillation are rare and comparable between warfarin and apixaban. (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation [ARISTOTLE]; NCT00412984).
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, University of Missouri, Columbia, Missouri. Electronic address: flakerg@missouri.edu.
authors.forename: Greg
authors.initials: G
authors.lastname: Flaker
authors.affiliation: Division of Cardiology, Department of Medicine, Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina.
authors.forename: Renato D
authors.initials: RD
authors.lastname: Lopes
authors.affiliation: Division of Cardiology, Department of Medicine, Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina.
authors.forename: Sana M
authors.initials: SM
authors.lastname: Al-Khatib
authors.affiliation: Department of Electrocardiology, Instituto Nacional de Cardiologia, "Ignacio Chavez," Juan Badiano #1, Seccion XVI, Tlalpan, Mexico.
authors.forename: Antonio G
authors.initials: AG
authors.lastname: Hermosillo
authors.affiliation: J.W. Goethe-University, Frankfurt, Germany.
authors.forename: Stefan H
authors.initials: SH
authors.lastname: Hohnloser
authors.affiliation: Division of Cardiology, Department of Medicine, Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina.
authors.forename: Brian
authors.initials: B
authors.lastname: Tinga
authors.affiliation: Fuwai Hospital, Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhu
authors.affiliation: Bristol-Myers Squibb, Princeton, New Jersey.
authors.forename: Puneet
authors.initials: P
authors.lastname: Mohan
authors.affiliation: University of New Mexico, Albuquerque, New Mexico.
authors.forename: David
authors.initials: D
authors.lastname: Garcia
authors.affiliation: Cardiologisch Centrum, OLV Zienkenhuis, Aalst, Belgium.
authors.forename: Jozef
authors.initials: J
authors.lastname: Bartunek
authors.affiliation: University of Medicine and Pharmacy Carol Davila, Bucharest, Romania.
authors.forename: Dragos
authors.initials: D
authors.lastname: Vinereanu
authors.affiliation: Department of Cardiology, Århus University Hospital, Århus, Denmark.
authors.forename: Steen
authors.initials: S
authors.lastname: Husted
authors.affiliation: Division of Emergency Care, Department of Medicine, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Veli Pekka
authors.initials: VP
authors.lastname: Harjola
authors.affiliation: Department of Clinical Science and Education, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Marten
authors.initials: M
authors.lastname: Rosenqvist
authors.affiliation: Division of Cardiology, Department of Medicine, Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina.
authors.forename: John H
authors.initials: JH
authors.lastname: Alexander
authors.affiliation: Division of Cardiology, Department of Medicine, Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina.
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Granger
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000009:adverse effects / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000188:drug therapy* / Q000401:mortality / Q000628:therapy; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D017548:Echocardiography, Transesophageal / Q000379:methods; D004554:Electric Countershock / Q000009:adverse effects / Q000379:methods*; D004562:Electrocardiography / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006470:Hemorrhage; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000517:prevention & control; D061214:Patient Safety; D011720:Pyrazoles / Q000627:therapeutic use*; D011728:Pyridones / Q000627:therapeutic use*; D018570:Risk Assessment; D012720:Severity of Illness Index; D020521:Stroke / Q000517:prevention & control; D015996:Survival Rate; D013923:Thromboembolism / Q000517:prevention & control; D016896:Treatment Outcome; D014859:Warfarin / Q000627:therapeutic use*
chemical_list: D000925:Anticoagulants; D011720:Pyrazoles; D011728:Pyridones; C522181:apixaban; D014859:Warfarin
keywords: atrial fibrillation; cardioversion; factor Xa inhibitor; thromboembolic events; vitamin K antagonist