Effects of chronic omega-3 polyunsaturated fatty acid supplementation on human atrial electrophysiology

Heart Rhythm. 2011 Apr;8(4):562-8. doi: 10.1016/j.hrthm.2010.12.017. Epub 2010 Dec 13.

Abstract

Background: Omega-3 polyunsaturated fatty acids in fish oils may have antifibrillatory effects. Their mechanism of action in humans is poorly understood.

Objective: The purpose of this study was to investigate the effects of chronic fish oil supplementation on human atrial electrophysiology (EP).

Methods: Two groups of patients without clinical AF or structural heart disease and fish intake ≤1/week were prospectively recruited into a control group (n = 30) and a fish oil group (n = 31). The latter were prescribed 6 g/day of fish oil for ≥1 month before an EP study. The following were compared at time of EP study: serum omega-3 levels; right atrial and coronary sinus effective refractory periods (ERPs); interatrial, intra-atrial, left atrial, and coronary sinus conduction at baseline and the maximal conduction delay with the shortest propagated extrastimulus; and inducibility of AF (10 inductions/patient).

Results: The following significant differences were noted favoring the fish oil group at time of EP: (1) twofold higher total omega-3 levels (P < .001); (2) lengthening of ERPs by 8%-14% at all measured sites and pacing cycle lengths (P < .05); (3) no effect on baseline interatrial, intra-atrial, left atrial, and coronary sinus conduction but a significant attenuation of maximal conduction delay (P < .05); (4) less inducible AF (AF ≥30 seconds: 24.2% vs. 7.9%; P < .001); (5) shorter mean duration of induced AF (P = .003); and (6) prolongation of induced AF cycle length (P < .001).

Conclusions: Chronic fish oil supplementation in humans prolongs atrial refractoriness and reduces vulnerability to inducible AF. These EP changes may explain the antifibrillatory effect of chronic fish oil ingestion.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Adolescent
  • Adult
  • Aged
  • Atrial Fibrillation / prevention & control
  • Atrial Function / drug effects
  • Atrial Function / physiology*
  • Dietary Supplements*
  • Dose-Response Relationship, Drug
  • Electrocardiography*
  • Electrophysiological Phenomena / drug effects*
  • Fatty Acids, Omega-3 / administration & dosage*
  • Female
  • Fish Oils / administration & dosage
  • Follow-Up Studies
  • Heart Atria / drug effects*
  • Humans
  • Male
  • Middle Aged
  • Prospective Studies
  • Single-Blind Method
  • Young Adult

Substances

  • Fatty Acids, Omega-3
  • Fish Oils