N-3 polyunsaturated fatty acids prevents sterile pericarditis-induced atrial fibrillation by inhibiting oxidative stress in canine

Objective To study the anti-arrhythmic and anti-oxidative stress effects of n-3 polyunsaturated fatty acids (PUFAs) in a canine sterile pericarditis model. Methods A total of 20 dogs were randomly assigned to two groups: a control group (10 dogs) and a PUFAs treatment group (10 dogs), with sterile pericarditis created by open-chest operation in both groups. PUFAs was administered orally (2 g/d) 4 weeks before the operation until the end of the study. The inducibility and maintenance of atrial fibrillation (AF), atrial effective refractory period (AERPs), and intra-atrial conduction time were determined before and 2 days after the operation. And the level of 3-nitrotyrosine in the atrial tissue was determined by Western blotting analysis. Results The electrophysiology parameters were similar between the two groups. On day 2 after operation, the PUFAs group compared with the control group had a significantly lower AF inducibility ([11.0 ± 7.4]% vs [28.0 ± 10.3] %, P < 0.001) and maintenance (median AF duration: 1105 [655.8-1406.5] s vs 2516.5 [1187-3361] s, P< 0.05), a significantly longer AERP ([133.4 ± 4.1] ms vs [129.8 ± 4.3] ms, P < 0.05), and a significantly shorter intra-atrial conduction time ([46.6 ± 4.4] vs [51.9 ± 4.8] ms, P < 0.05). Western blotting analysis showed that 3-nitrotyrosine level in the atrial tissue of PUFAs group was signiticantly lower than that of the control group (P < 0.0001). Conclusion Dietary PUFAs supplementation can reduce the risk of AF after operation, and its anti-oxidative stress effect might be one of the mechanisms.