Background: Novel facilities such as an intensive observation unit and an outpatient clinic could result in improving management of patients presenting with atrial fibrillation (AF). Methods: This observational study enrolled 3475 patients. Group 1 (1120 patients; years [2004][2005] was managed with standard approach; group 2 (992 patients; years [2006][2007] was managed with additional intensive observation; group 3 (1363 patients; years 2008-2009) was managed with additional intensive observation and outpatient clinic. Primary end point was admission to hospital. Secondary end points included modalities of rhythm conversion and administration of class IC vs class III antiarrhythmic drugs in patients with AF lasting less than 48 hours. Results: Lack of rhythm control, comorbidities, diabetes, and age were independent predictors of hospitalization. Admissions significantly decreased from group 1 (50%) to 2 (38%) and to 3 (24%) (P b .001). Interestingly, more than a quarter of patients in group 3 were referred to the outpatient clinic for short-term follow-up, eventually avoiding admission. Patients with AF lasting less than 48 hours (n = 2189) and without structural heart disease (n = 1685) achieved sinus rhythm in 89% of cases and were discharged. In these patients, early administration of antiarrhythmic drugs of class IC and III gained sinus rhythm in 80% and 20%, respectively (P b .001). Spontaneous conversion occurred in 26%; electrical, 17%; and pharmacological, 57%. Conclusions: In patients with AF, beyond the standard approach, the novel organization with an additional intensive observation unit for early pharmacological interventions and an outpatient clinic for elective treatment and short-term follow-up significantly reduced admission irrespective of independent predictors of hospitalizations. Patients without structural heart disease treated with antiarrhythmic drugs achieved sinus rhythm in 89% of cases, mostly with class IC drugs.