Stiell IG, Eagles D, Nemnom MJ, et al. - Electrical cardioversion (ECV) rarely resulted in serious adverse events when performed for acute atrial fibrillation (AF)/atrial flutter (AFL) in the emergency department (ED), however, a concerning number of events occurred post-sedation that required intervention.

• Data were extracted from four multicentre AF/AFL studies done between 2008 and 2019 at 23 large EDs.

• Analysis involved 1,736 ECV cases with mean age 60.1 years and male 67.1%.

• ECV had overall success of 90.2% (95% CI 88.7-91.6%) with 4.9% of patients admitted.

• ECV was conducted in 95.2% and sedation was given in 96.5%.

• Important adverse events necessitating treatment occurred in 13.9% (12.3-15.7%) of cases; of those, 0.4% were life-threatening.

• A higher risk of important adverse events was found in relation to older age, coronary artery disease, and fentanyl.