APAF Apixaban in Atrial Fibrillation Registry

Atrial fibrillation (AF) confers a substantial risk of mortality and morbidity from stroke and thromboembolism, and this common cardiac arrhythmia represents a major healthcare burden in Europe. Stroke prevention is central to the management of AF patients, with oral anticoagulation (OAC) using well-controlled adjusted dose vitamin K antagonists or novel OACs being recommended for patients with AF with ≥1 stroke risk factors. Also, the 2012 focused update of the ESC guidelines strongly advocates a clinical practice shift so that the initial decision step now is the identification of 'truly low risk' patients, essentially those age<65 without any stroke risk factors (both male and female), who do not need any antithrombotic therapy. The ESC guidelines only recommend use of the CHA2DS2-VASc score for stroke risk assessment, and the 'low risk' patients are defined as those with a CHA2DS2-VASc score=0 (males) or score=1 (females). Subsequent to this initial step of identifying the low risk patients, effective stroke prevention (which is essentially OAC) can then be offered to AF patients with ≥1 stroke risk factors, with treatment decisions made in consultation with patients and incorporating their preferences. Despite these recommendations, a substantial number of patients with AF is not treated with OAC. On the other hand, patients with AF and low risk are being "overtreated", receiving OAC despite a CHADS-VASc score of 0. Therefore, this registry will determine, if patients with non-valvular AF are treated ac-cording to current guidelines.

Apixaban is an oral factor Xa inhibitor, which has been tested in a number of indications. In the AVERROES study in patients with non-valvular atrial fibrillation deemed not suitable for treatment with a vitamin-K antagonist apixaban compared to aspirin reduced the incidence of stroke and systemic embolism without increasing bleeding complications. In the large ARISTOTELE study apixaban was superior to warfarin, it re-duced the primary endpoint of stroke and systemic embolism caused less bleeding and reduced all-cause mortality. Subsequently apixaban has been approved by the European health authorities for the use in patients with atrial fibrillation. It is therefore of interest to determine use of apixaban in real life with respect to patient selection, adherence to therapy and midterm efficacy and safety.