To demonstrate that in patients with persistent atrial fibrillation who had recovered normal sinus rhythm and treated with the best recommended therapies, the addition of 1 gram / daily of n-3 PUFA is superior to the corresponding placebo for the maintenance of normal sinus rhythm at one year of follow up.

Atrial fibrillation (AF) impose a substantial and growing economic burden on health care expenditures. In patients with persistent AF, there are fundamentally two ways to manage the arrhythmia: to restore and maintain sinus rhythm (rhythm control) or to allow AF to continue and ensure that the ventricular rate is controlled (rate control). As it has been stated, it goes without saying that if we could prevent atrial fibrillation (AF) or restore and maintain sinus rhythm in patients suffering from persistent AF, without any penalties due to the unwanted effects of drugs or incomplete suppression of AF and its thromboembolic complications, every physician would do so. Current strategies however, are limited to achieve such desirable goal. In the last years a growing amount of evidence and attention regarding the cardio-protective role of Omega 3 fatty acids (n-3 PUFA) became progressively clear and appealing.

Epidemiological studies and randomized controlled trials confirms the role of n-3 PUFA in reducing all cause mortality and cardiovascular events mostly in patients at high cardiovascular risk. These effects seems to be mediated mostly by an anti-arrhythmogenic effect.

Basic science confirms and extended clinical observations regarding the antiarrhythmogenic effect of these compounds. Recently both basic research and clinical science suggested a role of n-3 PUFA for the prevention and treatment of supraventricular arrhythmias, particularly AF.

The purpose of the study is to show that the addition of n-3 PUFA on the top of the best recommended therapies can improve the maintenance of normal sinus rhythm in patients with persistent atrial fibrillation.

Inclusion Criteria:

• Persistent atrial fibrillation

Exclusion Criteria:

• Contraindications or known hypersensitivity to n-3 PUFA
• Current treatment with n-3 PUFA for any reason
• Heart failure NYHA class IV
• Coronary artery bypass surgery or valve replacement within the past 3 months
• Planned cardiac procedures
• Known sick-sinus syndrome
• Diagnosis of Wolff-Parkinson-White
• Clinical significant valvular etiologies
• Presence of arrhythmia associated with an acute reversible condition
• Advanced chronic lung disease
• Contraindications for anticoagulation therapy
• Pregnancy or lactation
• Any non cardiac illness associated with a life expectancy of < 2 years
• Treatment with any investigational agent within 3 month before randomization
• Any condition that in the opinion of the investigator would jeopardize the evaluation of efficacy or safety or be associated with poor adherence to the protocol