title: Prognostic factors of atrial fibrillation following elective coronary artery bypass grafting: the impact of quantified intraoperative myocardial ischemia.
abstract: BACKGROUND
  Atrial fibrillation (AF) occurs in 28-33% of the patients undergoing coronary artery revascularization (CABG). This study focuses on both pre- and peri-operative factors that may affect the occurrence of AF. The aim is to identify those patients at higher risk to develop AF after CABG.
  
  
  METHODS
  Two patient cohorts undergoing CABG were retrospectively studied. The first group (group A) consisted of 157 patients presenting AF after elective CABG. The second group (group B) consisted of 191 patients without AF postoperatively.
  
  
  RESULTS
  Preoperative factors presenting significant correlation with the incidence of post-operative AF included: 1) age > 65 years (p = 0.029), 2) history of AF (p = 0.022), 3) chronic obstructive pulmonary disease (p = 0.008), 4) left ventricular dysfunction with ejection fraction < 40% (p = 0.015) and 5) proximal lesion of the right coronary artery (p = 0.023). The intraoperative factors that appeared to have significant correlation with the occurrence of postoperative AF were: 1) CPB-time > 120 minutes (p = 0.011), 2) myocardial ischemia index < 0.27 ml.m2/Kg.min (p = 0.011), 3) total positive fluid-balance during ICU-stay (p < 0.001), 4) FiO2/PO2 > 0, 4 after extubation and during the ICU-stay (p = 0.021), 5) inotropic support with doses 15-30 μg/Kg/min (p = 0.016), 6) long ICU-stay recovery for any reason (p < 0.001) and perioperative myocardial infarction (p < 0.001).
  
  
  CONCLUSIONS
  Our results suggest that the incidence of post-CABG atrial fibrillation can be predicted by specific preoperative and intraoperative measures. The intraoperative myocardial ischemia can be sufficiently quantified by the myocardial ischemia index. For those patients at risk we would suggest an early postoperative precautionary anti-arrhythmic treatment.
authors.affiliation: Cardiothoracic Surgery Department, University of Patras, School of Medicine, Patras, Greece.
authors.forename: Efstratios N
authors.initials: EN
authors.lastname: Koletsis
authors.forename: Christos
authors.initials: C
authors.lastname: Prokakis
authors.forename: James R
authors.initials: JR
authors.lastname: Crockett
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Dedeilias
authors.forename: Matthew
authors.initials: M
authors.lastname: Panagiotou
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Panagopoulos
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Anastasiou
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Dougenis
authors.forename: Efstratios
authors.initials: E
authors.lastname: Apostolakis
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000453:epidemiology* / Q000209:etiology* / Q000503:physiopathology; D016009:Chi-Square Distribution; D001026:Coronary Artery Bypass / Q000379:methods*; D005260:Female; D006801:Humans; D015994:Incidence; D007431:Intraoperative Complications / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000150:complications* / Q000503:physiopathology; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome