Safety of Cardioversion of Acute Atrial Fibrillation

The purpose of this study is to investigate the complications of cardioversion of acute (\<48 hours duration) atrial fibrillation (AF). Primary Outcome Measures: \- Incidence and predictors of thromboembolic complications, especially stroke, and death \<31 days after cardioversion of acute AF Secondary Outcome Measures: * Number of therapy non-responder and early recurrence of AF * Bleeding complications during the 31 days follow-up * Hemodynamic complications of cardioversion Estimated Enrollment: 3000 cases Study Start Date: Jun 2011 Estimated Study Completion Date: December 2011