Abstract
Risk factors for stroke and thromboembolism in patients with atrial fibrillation used in current risk stratification schema are derived largely from analyses of clinical trial cohorts, and the available data depend on the comprehensiveness of trial reports and whether specific risk factors were sought. The most commonly used schema is the Cardiac failure, Hypertension, Age, Diabetes, Stroke [Doubled] (CHADS2) score. Although simple and well validated, some limitations of CHADS2 this schema are apparent. A more recent approach to risk stratification of patients with nonvalvular atrial fibrillation defines “major (definitive)” risk factors (eg, previous stroke/transient ischemic
