Investigators developed a multidimensional protocol for the management of AF in the emergency department. Investigators aimed to assess if this new ER AF management protocol would result in better outcomes compared to routine care.

Management variation such as selecting rate vs rhythm control, timing and need for thromboembolic treatment, ER vs inpatient treatment and cardiology consultation could lead to disparate care of patients. Therefore, there is a need for future studies to standardize practice leading to improved management, decreased rates of hospitalization and overall cost. Investigators developed a multidimensional protocol for the management of AF in the emergency department. Investigators aimed to assess if this new ER AF management protocol would result in better outcomes compared to routine care.

Inclusion Criteria:

• Consecutive patients > 18 years of age who comes to the ER with AF as the primary diagnosis and is treated according to study protocol.

Exclusion Criteria:

• Patients with established cardiology or electrophysiology care.

i) Study arm: Patients > 18 years of age (both males and females) who present with AF as the primary diagnosis to the ER will have their chart reviewed.

ii) Historical control arm:Historical control arm will be selected from chart review of emergency department prior to the commencement of this study after propensity matching with age and sex. All patients > 18 years of age (both males and females) who presented with AF as primary diagnosis to the ER of the participating centers within last 2 years will be selected if they meet the inclusion/exclusion criteria mentioned below