Upstream Treatment of Atrial Fibrillation with n-3 Polyunsaturated Fatty Acids: Myth or Reality?

Atrial fibrillation (AF) is the most common sustained arrhythmia in adults and is associated with an increased risk of fatal and non-fatal events. Antiarrhythmic drugs provide limited protection against AF recurrence and have a poor safety profile. Several mechanisms have been proven to be involved in AF, e.g. inflammation, oxidative stress, fibrosis and ischaemia. Prevention of AF with interventions that target these mechanisms has emerged as a result of experimental studies suggesting the use of upstream therapies. Long chain n-3 polyunsaturated fatty acids (n-3 PUFA) have multiple effects on cardiac electrophysiology, and epidemiological studies on fish oil suggest a possible use of n-3 PUFA in AF prevention. Several randomised clinical trials have been designed to evaluate the efficacy of n-3 PUFA in preventing AF. In this review, we report the conflicting results of these trials in two different clinical settings: recurrence in patients with history of AF and development of post-operative AF in patient undergoing cardiac surgery.