Original ContributionsAn emergency department observation unit protocol for acute-onset atrial fibrillation is feasible*,**,*
Introduction
Atrial fibrillation is the most common cardiac arrhythmia managed in the emergency department.1 It results from the chaotic depolarization of atrial tissue.2 It is associated with a reduction in cardiac output3 and an increased risk of stroke. Atrial fibrillation accounts for 30,000 to 40,000 strokes per year in the United States.4
Acute-onset atrial fibrillation (AAF; or new-onset, paroxysmal atrial fibrillation) is defined as atrial fibrillation in which symptoms have lasted for less than 48 to 72 hours. Because atrial fibrillation leads to changes within the heart that perpetuate it (atrial fibrillation begets atrial fibrillation), cardioversion to sinus rhythm is more likely to be successful the sooner it is conducted.5 For this reason, patients presenting to the ED with AAF benefit from timely restoration of sinus rhythm. Traditionally, when initial conversion to sinus rhythm fails, these patients are admitted to the hospital to achieve rate control, to restore sinus rhythm, and to monitor for comorbidities or complications, such as myocardial infarction or embolic events. The incidence of serious cardiovascular complications within this group may be as high as 20%.6 It has been reported that hospital lengths of stay for atrial fibrillation are markedly greater than for any other arrhythmia.7, 8 However, a subset of patients with AAF that may not require inpatient admission has been described. Recent studies suggest that approximately one third of admitted patients with AAF may not have required inpatient admission.9 Others have proposed that stable patients with recent-onset atrial fibrillation may avoid hospitalization by using a combination of initial rate control and various therapies to encourage conversion to sinus rhythm.10
Studies in Canada and Australia have suggested that many patients with AAF may be safely managed in the ED and discharged.11, 12, 13 In the United States, there has been growing interest in the ED observation unit (EDOU) as an alternative to inpatient admission. In this setting, patients with other conditions are aggressively managed with accelerated treatment or diagnostic protocols, resulting in high discharge rates, lower costs, and improved satisfaction.14, 15, 16, 17, 18 It would seem that the EDOU would be an ideal alternative to inpatient admission for the management of stable patients with AAF presenting to the ED. However, there are currently no studies of AAF managed in an EDOU setting.
In this study, we report the outcomes of an EDOU treatment protocol for the management of patients with AAF in whom initial ED therapy has failed.
Section snippets
Materials and methods
This is a prospective descriptive case series of patients enrolled in an EDOU treatment protocol for the management of AAF. This study was conducted in the ED at the William Beaumont Hospital, a high-volume, university-affiliated, suburban teaching hospital. The study was granted an institutional review board exemption at the study hospital. The EDOU has been operational since 1995 and complies with the American College of Emergency Physicians' guidelines for the management of an EDOU.19, 20
Results
Over the study period, 259,175 patients were seen in the ED. Of these, 2,750 (1.06%) had the ICD-9 code for atrial fibrillation coded in their medical record. On chart review, 65% (1,788) were seen for treatment of chronic atrial fibrillation and 35% (125) for AAF, yielding an estimated 962 patients with AAF. Of patients with AAF, 13% converted in the ED and were discharged home, 80% (770) were admitted as an inpatient, and 7% (67 patients) were treated in the EDOU and are detailed in this
Discussion
We found that, for a selected subset of ED patients with uncomplicated AAF, management in an EDOU was a feasible alternative to inpatient admission. We describe a basic protocol for the management of these patients that contains both therapeutic and diagnostic components. By using this protocol, high rates of conversion to sinus rhythm and discharge can be expected, and latent occult pathology may be identified. No previous studies have addressed the treatment of AAF in an EDOU. A previous
Addendum
The recent decision by the Centers for Medicare and Medicaid Services to separately fund observation services for only the 3 most well-studied conditions (chest pain, asthma, and congestive heart failure) underscores the need to further study other conditions that may be amenable to EDOU treatment. A copy of the Federal Register comments made by the Centers for Medicare and Medicaid Services can be accessed at www.hcfa.gov/regs/Pp44671.pdf.26
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2019, Canadian Journal of CardiologyCitation Excerpt :Conversely, patients who present with symptomatic AF/AFL of < 48 hours’ duration have long been considered, on a theoretical basis, to have a low risk of thromboembolism after CV. This practice has been supported by several observational reports of short-term outcomes after CV in patients with acute AF, in which only 12 patients experienced thromboembolism in the 30 days after CV (0.27% monthly risk; 4836 CVs; 4380 patients).8,26,27,29-40 Although this risk is comparable with that of elective CV in chronic AF/AFL patients who receive OACs, the observed 30-day rate of thromboembolism far exceeds the expert consensus-based Canadian Cardiovascular Society (CCS) AF guideline threshold for recommending OACs (1.5% per year, or 0.12% per 30 days).41-43
2018 Focused Update of the Canadian Cardiovascular Society Guidelines for the Management of Atrial Fibrillation
2018, Canadian Journal of CardiologyThe Establishment and Management of an Observation Unit
2017, Emergency Medicine Clinics of North AmericaCardiovascular Conditions in the Observation Unit: Beyond Chest Pain
2017, Emergency Medicine Clinics of North AmericaCitation Excerpt :The most important aspect of patient education is emphasizing the importance of early outpatient follow-up. In order for patients to be discharged from the EDOU, they must demonstrate clinical stability with either their AF rate controlled or their rhythm converted to normal sinus for at least 1 to 2 hours.1 Most EDOU protocols also require negative serial cardiac biomarker tests before discharge if ACS is suspected as a contributory factor.1
Thirty-day and 1-year outcomes of emergency department patients with atrial fibrillation and no acute underlying medical cause
2012, Annals of Emergency MedicineTransforming the Emergency Department Observation Unit. A Look Into the Future
2012, Cardiology Clinics
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Author contributions are provided at the end of this article.
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Address for reprints: Michael A. Ross, MD, 3601 West Thirteen Mile Road, Royal Oak, MI 48073-6769; 248-551-3080 or 248-551-2016; E-mail [email protected]
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Author contributions: MAR and BOK conceived the study, and REJ worked with them to refine its design. BOK conducted data collection. MAR, REJ, and BOK all analyzed and interpreted the data. MAR and BOK drafted the manuscript, while MAR, BOK, and REJ all contributed to revisions. MAR and BOK take responsibility for the paper as a whole.