Interhospital Variability in Utilization of Cardioversion for Atrial Fibrillation in the Emergency Department

The role for direct current cardioversion (DCCV) in the management of atrial fibrillation (AF) in the emergency department (ED) is unclear. Factors associated with DCCV in current practice are not well described, nor is the variation across patients and institutions. All ED encounters with a primary diagnosis of AF were identified from the Nationwide Emergency Department Sample from 2006 to 2017. The independent association of patient and hospital factors with use of DCCV was assessed using multivariable hierarchical logistic regression. The relative contributions of patient, hospital, and unmeasured hospital factors were assessed using reference effect measures methods. Among 1,280,914 visits to 3,264 EDs with primary diagnosis of AF, 31,422 patients (2.4%) underwent DCCV in the ED. History of stroke (odds ratio [OR] 0.14, 95% confidence interval [CI] 0.09 to 0.22, p <0.001) and dementia (OR 0.14, 95% CI 0.10 to 0.19, p <0.001) was associated with lowest odds of DCCV. Comparing patients more likely to receive DCCV (ninety-fifth percentile) with patients with median risk, the influence of unmeasured hospital factors (OR 14.13, 95% CI 12.55 to 16.09) exceeded the contributions of patient (OR 5.66, 95% CI 5.28 to 6.15) and measured hospital factors (OR 3.89, 95% CI 2.87 to 5.60). In conclusion, DCCV use in the ED varied widely across institutions. Disproportionately large unmeasured hospital variation suggests that presenting hospital is the most determinative factor in the use of DCCV for ED management of AF. Clarification is needed on best practices for management of AF in the ED, including the use of DCCV.