title: Plasma n-3 and n-6 fatty acids and the incidence of atrial fibrillation following coronary artery bypass graft surgery.
abstract: BACKGROUND
  The anti-inflammatory or anti-arrhythmic effects of n-3 long-chain polyunsaturated fatty acids (LC-PUFA) may decrease the risk of postoperative atrial fibrillation (POAF), but interventional studies have yielded conflicting results. We examined the association between n-3 LC-PUFA and n-6 LC-PUFA in plasma phospholipids (PL) and POAF in patients undergoing coronary artery bypass grafting (CABG).
  
  
  METHODS
  A total of 125 patients undergoing CABG were enrolled in the study. The levels of fatty acids in PL were measured preoperatively and on the third postoperative day. The endpoint was defined as POAF lasting ≥5 min. The incidence of POAF was compared between quartiles of the level of each fatty acid in plasma PL by univariate and multivariable analysis.
  
  
  RESULTS
  The incidence of POAF was 49·6%. By univariate analysis, the incidence of POAF increased significantly with each higher quartile of pre- and postoperative docosahexaenoic acid (DHA) and diminished significantly with each higher quartile of pre- and postoperative arachidonic acid (AA). For postoperative total n-3 LC-PUFA, there was a significant U-curve relationship where the second quartile had the lowest incidence of POAF or 25·8%. In multivariable analysis, this U-curve relationship between n-3 LC-PUFA levels and POAF risk was not significant, whereas the association between POAF and DHA or AA remained statistically significant.
  
  
  CONCLUSIONS
  This study suggests that n-3 LC-PUFA supplements might prevent POAF in CABG patients with low baseline levels of these fatty acids in plasma PL, but may be harmful in those with high levels. AA may play an important role in electrophysiological processes.
authors.affiliation: Department of Physiology, School of Health Sciences, University of Iceland, Reykjavik, Iceland. gudrunvs@hi.is
authors.forename: Gudrun V
authors.initials: GV
authors.lastname: Skuladottir
authors.forename: Ragnhildur
authors.initials: R
authors.lastname: Heidarsdottir
authors.forename: David O
authors.initials: DO
authors.lastname: Arnar
authors.forename: Bjarni
authors.initials: B
authors.lastname: Torfason
authors.forename: Vidar
authors.initials: V
authors.lastname: Edvardsson
authors.forename: Gizur
authors.initials: G
authors.lastname: Gottskalksson
authors.forename: Runolfur
authors.initials: R
authors.lastname: Palsson
authors.forename: Olafur S
authors.initials: OS
authors.lastname: Indridason
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000097:blood*; D002097:C-Reactive Protein / Q000378:metabolism; D001026:Coronary Artery Bypass; D004311:Double-Blind Method; D005227:Fatty Acids / Q000097:blood; D015525:Fatty Acids, Omega-3 / Q000097:blood*; D043371:Fatty Acids, Omega-6 / Q000097:blood*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010743:Phospholipids / Q000097:blood; D011183:Postoperative Complications; D011446:Prospective Studies
chemical_list: D005227:Fatty Acids; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D010743:Phospholipids; D002097:C-Reactive Protein