[Update on the prevention of thromboembolic phenomena in atrial fibrillation].

Atrial fibrillation is the most common sustained arrhythmia in clinical practice and is associated to thromboembolic complications. Anticoagulation with vitamin K antagonists is clearly useful to reduce the incidence of emboli, but associated with important limitations. Therefore, there is an active search for medications that are more effective and simpler to prescribe and manage. Synthetic pentasaccharides of heparin such as idraparinux for parenteral use, showed promising results. Direct inhibitors of thrombin were also useful for the prevention of thromboembolism. However, they were withdrawn from the market due to potentially fatal adverse reactions. Other area of investigation has been the effectiveness of the combination of antiplatelet agents such as aspirin and clopidrogel. Although this combination is attractive, results of clinical trials must be awaited to have an opinion about its real usefulness. Finally, left atrial appendage transcatheter occlusion (PLAATO) is an effective and reasonably safe method for patients with contraindications for anticoagulation or those that continue to embolize despite well prescribed anticoagulation. The long term results of this intervention must also be awaited.