Troponin utilization in patients presenting with atrial fibrillation/flutter to the emergency department: retrospective chart review

We performed a retrospective chart review of patients with atrial fibrillation/flutter presenting to the emergency department at three centers. Outcome measures included the rates of troponins ordered by emergency doctors, number of positive troponins, and those with positive troponins treated as acute coronary syndrome (ACS) by consulting services.Four hundred fifty-one charts were reviewed. A total of 388 (86%) of the patients had troponins ordered, 13.7% had positive results, and 4.9% were treated for ACS.Troponin tests are ordered in a high percentage of patients with atrial fibrillation/flutter presenting to emergency departments. Five percent of our total patient cohort was diagnosed as having acute coronary syndrome by consulting services.The prevalence of atrial fibrillation is estimated at 0.1% among adults younger than 55 years, rising with age to 9% in those older than 80 [1,2], with clear implications in resource utilization by an aging population. It is estimated that the number of patients with atrial fibrillation will rise to about 5.6 million in 2050 from its current number of 2.3 million cases [3]. Atrial fibrillation is a resource-intensive arrhythmia as 70-80% of these patients are admitted during the course of their illness [4]. More importantly, a number of studies have shown that the hospitalization rates for atrial fibrillation have increased, up to 2-3 fold in the last 2 decades [5,6].Though there are few recommendations about the use of cardiac markers in the investigation and management of atrial fibrillation [7,8], these tests are often ordered to diagnose myocardial infarction as the cause or consequence of the arrhythmia in patients with atrial fibrillation or flutter that present to emergency departments. Unnecessary use of cardiac markers may contribute to emergency department laboratory costs, delays in patient discharge if using serial tests, and unnecessary admission and cardiac investigations for positive troponins of unknown signi