N-3 polyunsaturated fatty acids prevents atrial fibrillation by inhibiting inflammation in a canine sterile pericarditis model

Objective: It has been recently reported that atrial fibrillation (AF) is associated with inflammation and inflammatory cytokines, and n-3 polyunsaturated fatty acids (PUFAs) might be of anti-inflammatory effects. This study was to evaluate the anti-inflammatory effect of PUFAs on AF in a canine sterile pericarditis model. Methods: 20 dogs were randomly assigned to two groups: control group (10 dogs) and PUFA treatment group (10 dogs), in which sterile pericarditis was created by open-chest operation. PUFAs were administered orally (2 g/day) 4 weeks before the operation till the end of the study. Before and 2 days after the operation, CRP, IL-6, TNF-α levels, the inducibility and maintenance of AF, the atrial effective refractory period (AERPs), and intra-atrial conduction time were determined. Results: Before the operation, there were no significant differences in any of the parameters between the two groups. On the second postoperative day, the PUFA group had a lower CRP level (7.6 ± 0.5 vs. 11.7 ± 1.3 mg/dl, P < 0.0001), a lower IL-6 level (112.0 ± 37.3 vs. 142.0 ± 19.6 pg/ml, P < 0.01), a lower TNF-α level (83.3 ± 8.5 vs. 112.4 ± 8.2 pg/ml, P < 0.0001), a less AF inducibility (percentage of burst attempts leading to AF episodes: 11 ± 7.4 vs. 28 ± 10.3, P < 0.001) and maintenance [median AF duration: 1105 s (655.8-1406.5) vs. 2516.5 s (1187-3361), P < 0.05], a longer AERP (133.4 ± 4.1 vs. 129.8 ± 4.3 ms, P < 0.05), and a shorter intra-atrial conduction time (46.6 ± 4.4 vs. 51.9 ± 4.8 ms, P < 0.05) than the control group. Conclusions: Dietary n-3 PUFA supplementation attenuates the inducibility and maintenance of AF in the sterile pericarditis model by reducing the production of proinflammatory cytokines.