Abstract 15265: Extent of Elevation in Omega-3 Polyunsaturated Fatty Acid Levels in Blood is Directly and Strongly Related to Increases in Atrial Refractoriness and Susceptibility to Inducible Atrial Fibrillation in Humans
Background: The relationship between omega-3 polyunsaturated fatty acid (n-3 PUFA) intake and risk of atrial fibrillation (AF) has been inconsistent in epidemiological studies. Few studies have used blood markers to validate adequate n-3 PUFA exposure prior to assessment of AF risk.
Hypothesis: We hypothesised that heterogeneity in response to n-3 PUFA exposure as measured by blood markers is one possible explanation for the differences in the vulnerability to AF amongst populations.
Methods: Fifty seven patients with no structural heart disease or clinical AF underwent detailed electrophysiological evaluation. Twenty eight patients were on 6g/day of fish oil for ≥ 1 month, and 29 patients were not on fish oils. Serum eicosapentaenoicacid (DHA)+docosahexaenoic acid (DHA) in phospholipid fraction were measured. Atrial effective refractory periods and inducibility of AF were measured. Patients were divided into low, intermediate and highest tertiles of EPA+DHA levels.
Results: ERPs were shortest in the lowest tertile, longer in the intermediate and longest in the highest tertile of EPA+DHA at the proximal coronary sinus (P<0.002), distal coronary sinus (P<0.001) and the right atrial appendage (P<0.005). AF inducibility was highest in the lowest tertile, lower in the intermediate tertile, and lowest in the highest tertile of EPA+DHA (P=0.005). There was a modest correlation between serum EPA+DHA levels and ERPs at the right atrium (Pearson's r=0.73, P<0.001), proximal (r=0.56, P<0.001) and distal coronary sinus (r=0.59, P<0.001) and AF inducibility index (r=-0.44, P<0.001; Figure).
Conclusion: There is a modest and direct correlation between n-3 PUFA levels in blood and vulnerability to inducible AF. Higher n-3 PUFA levels are associated with longer atrial refractoriness and less inducible AF. This finding may account, in part, for the heterogeneity of results in clinical studies of n-3 PUFA exposure and risk of AF.
- © 2011 by American Heart Association, Inc.