title: Does warfarin help prevent ischemic stroke in patients presenting with post coronary bypass paroxysmal atrial fibrillation?
abstract: OBJECTIVE
  This study examines the efficacy of warfarin in preventing ischemic stroke due to paroxysmal atrial fibrillation (PAF) after coronary artery bypass grafting (CABG).
  
  
  METHODS
  Postoperative PAF occurred in 151(33.5%) of 447 patients undergoing conventional CABG. The patients were divided into two groups: group I consisting of 93 patients administered two types of antiplatelet agents and group II consisting of 58 patients treated with a single antiplatelet agent and warfarin. We compared the two groups in terms of CHADS2 score, incidence of ischemic stroke, and independent risk for stroke associated with post-CABG PAF.
  
  
  RESULTS
  The group I CHADS2 score (2.24 ±1.67) was significantly lower than the group II score (2.64 ± 1.22), p = 0.0452. However, 12 patients in group I (12.9%) suffered postoperative ischemic stroke, a rate significantly higher than that of group II (1 patient, 1.7%; p = 0.0173). Any recurrence of PAF or atrial fibrillation with bradycardia was assessed at the time of stroke onset. Logistic regression analysis showed that the absence of warfarin therapy constituted a risk factor for post-CABG stroke associated with PAF (Odds 13.04, p = 0.027).
  
  
  CONCLUSIONS
  Warfarin therapy administered concomitantly with an antiplatelet agent dramatically reduced the incidence of ischemic stroke associated with postoperative PAF.
authors.affiliation: Department of Cardiovascular Surgery, Nihon University Nerima Hikarigaoka Hospital, Tokyo, Japan. hata.mitsumasa@nihon-u.ac.jp
authors.forename: Mitsumasa
authors.initials: M
authors.lastname: Hata
authors.forename: Kenji
authors.initials: K
authors.lastname: Akiyama
authors.forename: Shinji
authors.initials: S
authors.lastname: Wakui
authors.forename: Ayako
authors.initials: A
authors.lastname: Takasaka
authors.forename: Akira
authors.initials: A
authors.lastname: Sezai
authors.forename: Motomi
authors.initials: M
authors.lastname: Shiono
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000188:drug therapy* / Q000209:etiology; D002545:Brain Ischemia / Q000209:etiology / Q000517:prevention & control*; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D012307:Risk Factors; D020521:Stroke / Q000209:etiology / Q000517:prevention & control*; D016896:Treatment Outcome; D014859:Warfarin / Q000627:therapeutic use*
chemical_list: D000925:Anticoagulants; D010975:Platelet Aggregation Inhibitors; D014859:Warfarin