Limitations
This study had several limitations. This was a retrospective study and there was no recorded reason for the decision as to where to undertake the cardioversion, nor were there data on the reasons to extend patient stay in the cardiology ward. There may have been patient differences not recorded in the data, or it may simply have been a matter of bed allocation.
One of the original study intentions was to collect sedation data along with immediate post-procedure complication data to see if these were related to the sedation or the procedure, but this data was scarce and was therefore ultimately not included in the study. Thus, post-procedure complication data should be cautiously interpreted. Regression analysis was not performed on the data, as most data were similar between the groups.
Many emergency departments may have a policy of automatically admitting patients with AF > 48 hours to a cardiology ward rather than treating them in the ED or an observation unit. Finally, the study was performed in one tertiary care medical center including a comprehensive cardiac institute, where the practice of ordering a TEE through the ED may not be generalizable to other institutions. Further prospective studies, perhaps of a randomized control design, would be better able to elucidate the safety and efficacy of performing TEE prior to electrical cardioversion of AF > 48 hours’ duration in the ED setting.