Risk of bleeding with long-term antithrombotic therapy in atrial fibrillation

The fear of bleeding complications is a common reason for withholding effective prophylaxis with vitamin K antagonists (VKAs) against thromboembolism. This article reviews the epidemiology of bleeding complications with VKAs, with particular emphasis on studies in patients with atrial fibrillation. Risk factors for bleeding, which can be divided into those related to excessive anticoagulant effect and/or those related to increased patient susceptibility, are discussed. The strongest risk factors can be built into models for predicting bleeding during anticoagulant therapy, and two such models that have been published are described. Finally, effective corrective treatment of excessive anticoagulation and bleeding episodes, that are crucial for the outcome and different modalities, are also reviewed.