title: Effects of high dose intravenous fish oil on human atrial electrophysiology: implications for possible anti- and pro-arrhythmic mechanisms in atrial fibrillation.
abstract: BACKGROUND
  Intravenous omega-3 polyunsaturated fatty acids (ω-3 PUFAs) may prevent atrial fibrillation (AF) inducibility and perpetuation in animal models. We examined the effect of high dose IV ω-3 PUFAs on human atrial electrophysiology.
  
  
  RESULTS
  We randomised 88 patients with no structural heart disease to receive saline (control group) or high dose IV ω-3 PUFA infusion prior to detailed atrial electrophysiologic evaluation. Biologically active components, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were measured in total lipids, free fatty acid and phospholipid (membrane incorporated) fraction pre and post infusion. Compared to pre-infusion values, EPA and DHA increased significantly in the total lipids and free fatty acid but were unchanged in the phospholipid fraction. IV ω-3 did not alter atrial refractory periods, however it slowed right, left and global atrial conduction (P<.05). Inducible AF was significantly less likely in ω-3 patients compared to controls (AF ≥ 5 min, 20% vs. 58%, P = .02) and was non-sustained (mean AF duration: 14s vs. 39 s, P<.001), however inducible and sustained atrial flutter was more common (≥ 5 min: 28% vs. 0%, P = .01). Organisation of AF into flutter was observed in a greater proportion of inductions in the ω-3 group (8.5% vs. 0.6%, P<.001).
  
  
  CONCLUSIONS
  IV ω-3 PUFAs (as free fatty acids) cause acute atrial conduction slowing, suppress AF inducibility, organise AF into atrial flutter and enhance atrial flutter inducibility. These findings provide a novel insight into potential anti and pro-arrhythmic mechanisms of fish oils in human AF.
authors.affiliation: Department of Cardiology, The Royal Melbourne Hospital, Parkville, Victoria, Australia; Department of Medicine, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Saurabh
authors.initials: S
authors.lastname: Kumar
authors.forename: Fiona
authors.initials: F
authors.lastname: Sutherland
authors.forename: Justin M S
authors.initials: JM
authors.lastname: Lee
authors.forename: Timothy
authors.initials: T
authors.lastname: Robinson
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Heck
authors.forename: Michael C G
authors.initials: MC
authors.lastname: Wong
authors.forename: Nicholas F
authors.initials: NF
authors.lastname: Kelland
authors.forename: Manohar L
authors.initials: ML
authors.lastname: Garg
authors.forename: Paul B
authors.initials: PB
authors.lastname: Sparks
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000188:drug therapy*; D016275:Atrial Function / Q000187:drug effects*; D055724:Electrophysiological Phenomena / Q000187:drug effects; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage* / Q000494:pharmacology*; D006801:Humans; D007262:Infusions, Intravenous; D008875:Middle Aged; D011446:Prospective Studies; D016037:Single-Blind Method; D055815:Young Adult
chemical_list: D015525:Fatty Acids, Omega-3
keywords: Atrial fibrillation; Atrial flutter; Electrophysiology; Fish oil; Omega-3 polyunsaturated fatty acids