title: Impact of epicardial anterior fat pad retention on postcardiothoracic surgery atrial fibrillation incidence: the AFIST-III Study.
abstract: OBJECTIVE
  We conducted a randomized, blinded, controlled study evaluating the impact of anterior fat pad (AFP) maintenance on postoperative atrial fibrillation (POAF) incidence.
  
  
  BACKGROUND
  Drugs with antiadrenergic effects reduce POAF. Because the epicardial AFP is parasympathetically innervated, its routine excision during coronary artery bypass grafting (CABG) might precipitate autonomic imbalance and induce POAF.
  
  
  METHODS
  Patients (n = 180, mean age = 66 +/- 10 years, 80% men, 5% with previous atrial fibrillation) undergoing CABG surgery were randomized to either AFP maintenance or AFP removal. Routine prophylaxis against POAF with beta-blockers (85%) and amiodarone (28%) was allowed on the basis of caregivers' discretion. The development of POAF, total hospital costs, and heart rate variability was compared between groups.
  
  
  RESULTS
  Anterior fat pad maintenance did not reduce POAF incidence (34.8% vs. 35.2%, p = 0.950) or total hospital costs (data as medians with 25%, 75% percentiles: 22,940 dollars [17,629 dollars, 29,274 dollars] vs. 23,866 dollars [18,602 dollars, 30,370 dollars], p = 0.647) but was associated with higher heart rate variability (SD of normal-to-normal RR intervals [SDNN]: 31.7 +/- 24.6 vs. 22.7 +/- 8.3, p = 0.05 and SD of all 5-min mean RR intervals [SDANN 5]: 17.1 +/- 11.9 vs. 10.1 +/- 5.5, p = 0.003) than AFP removal.
  
  
  CONCLUSIONS
  Maintaining the AFP prevents attenuation of parasympathetic tone after CABG but does not reduce POAF or total hospital costs in any appreciable way.
authors.affiliation: Division of Cardiology, Hartford Hospital, Hartford, Connecticut 06102-5037, USA.
authors.forename: C Michael
authors.initials: CM
authors.lastname: White
authors.forename: Stephen
authors.initials: S
authors.lastname: Sander
authors.forename: Craig I
authors.initials: CI
authors.lastname: Coleman
authors.forename: Robert
authors.initials: R
authors.lastname: Gallagher
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Takata
authors.forename: Chester
authors.initials: C
authors.lastname: Humphrey
authors.forename: Nickole
authors.initials: N
authors.lastname: Henyan
authors.forename: Effie L
authors.initials: EL
authors.lastname: Gillespie
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Kluger
mesh_terms: D000273:Adipose Tissue / Q000294:innervation* / Q000502:physiology; D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000368:Aged; D000638:Amiodarone / Q000627:therapeutic use; D000704:Analysis of Variance; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control; D001026:Coronary Artery Bypass / Q000009:adverse effects* / Q000379:methods; D003327:Coronary Disease / Q000175:diagnosis / Q000601:surgery*; D004311:Double-Blind Method; D015716:Electrocardiography, Ambulatory; D005260:Female; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010496:Pericardium / Q000294:innervation / Q000502:physiology; D011182:Postoperative Care; D011183:Postoperative Complications / Q000517:prevention & control; D011336:Probability; D011446:Prospective Studies; D018570:Risk Assessment; D016896:Treatment Outcome
chemical_list: D000319:Adrenergic beta-Antagonists; D000638:Amiodarone