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Goal of this article is to select three molecules from all the candidates currently under clincial development and to present and comapre their characteristics. Dabigatran is a direct thrombin (FIIa) inhibitor, whereas Rivaroxaban and Apixaban are direct factor Xa (FXa) inhibitors. All three represent small molecules that reversibly, rapidly and directly bind to their target, the active center of the respective activated coagulation factor. Phase III data have been published for venous thromboembolism prophylaxis for each of these three drugs. Interestingly, VTE prophylaxis is initiated postoperatively with these products. Rivaroxaban currently holds the only accepted indication in Switzerland. For the indications VTE, atrial fibrillation and acute coronary syndrome promising phase III data have been or are in the process of being published. Monitoring is not necessary for any of these three new anticoagulants. [ABSTRACT FROM AUTHOR]

By virtue of a severely prolonged aPTT with a normal thromboplastin time (prothrombin time) and a normal thrombin time, severe FXII deficiency has been diagnosed in a woman without a bleeding diathesis or a history of thromboembolic complications. A deficiency of a factor of the contact activation system (FXII, prekallikrein, high molecular weight kininogen) is usually diagnosed during routine coagulation tests demonstrating a prolonged aPTT. The severe and partial deficiency of FXII, of prekallikrein or high molecular weight kininogen is not associated with a bleeding tendency. In contrast, severely factor XI deficient subjects may suffer from a mild hemorrhagic diathesis, whereas FVIII deficiency (hemophilia A, autoimmune "hemophilia", von Willebrand disease) and FIX deficiency (hemophilia B) are associated with a bleeding tendency of varying severity, depending on the clotting activity of FVIII or FIX, respectively. An isolated prolongation of the aPTT due to a lupus anticoagulant, however, is frequently associated with arterial and/or venous thrombosis. Therefore, in case of a prolongation of the aPTT, its cause has to be determined.