Patients with atrial fibrillation (AF) who underwent percutaneous coronary intervention (PCI) are at elevated risk for bleeding and thromboembolic ischemic events. Currently, guidelines on antithrombotic treatment for these patients are based on weak consensus. We describe patterns and determinants of antithrombotic prescriptions in this population. The Antithrombotic Strategy Variability in Atrial Fibrillation and Obstructive Coronary Disease Revascularized with PCI Registry was an international observational study of 859 consecutive patients with AF who underwent PCI from 2009 to 2011.