Introduction: Following an emergency department (ED) presentation for acute atrial fibrillation and/or flutter (AF/AFL), patients often experience anxiety, depression and impaired health-related quality of life (QoL). Emergency physicians may prescribe appropriate thrombo-embolic (TE) prophylaxis upon discharge; however, the QoL of these patients is unclear. This study measured the QoL of patients with AF/AFL following discharge to determine the factors associated with QoL. Methods: Patients ≥18 years of age identified by the attending physician as having a diagnosis of acute AF/AFL confirmed by ECG were prospectively enrolled from three Edmonton, AB EDs. Using standardized enrollment forms, trained research assistants collected data on patient demographics factors and management both in the ED and at discharge. Patients’ health-related QoL was assessed up to 20 days after their initial ED visit by a telephone interview based on six domains of the short-form 8 health survey. Results: From a total of 196 enrolled patients, 121 (62%) were male and the mean age was 63 years (standard deviation ±14). Most patients had previous history of AF/AFL (71%), and emergency physicians had the opportunity to treat or revise TE prevention therapy in 19% of the patients. The majority (89%) were discharged with prescriptions for antiplatelet or anticoagulant agents, and 188 (96%) were contacted by telephone at a median of 7 days. Most patients rated their overall health between good and excellent (70%); however, 30% assessed their health as fair or very poor. Many also reported having physical limitations (54%), difficulties completing their daily work (42%), bodily pain (32%) and limitations in social activities (32%). Finally, some patients reported having low energy (25%). At follow up, patients receiving adequate TE prevention rated their health to be similar to those without adequate TE prevention (30% vs 23%; p=0.534). Conclusion: Overall, patients with acute, symptomatic AF/AFL seen in the ED have impairments in health-related QoL following discharge from the ED. Many factors contribute to this impairment; however, providing patients with appropriate TE prophylaxis at discharge did not explain these findings. Further research is required to explore the impact of AF/AFL on patient’s health-related QoL after discharge from the ED.