Original Contribution Abnormal troponin level as short-term predictor of poor outcome in acute atrial fibrillation Alberto Conti MD a, ⁎, Yuri Mariannini MD a , Gabriele Viviani MD a , Claudio Poggioni MD a , Gabriele Cerini MD a , Margherita Luzzi MD a , Maurizio Zanobetti MD a , Francesca Innocenti MD a , Luigi Padeletti MD b , Gian Franco Gensini MD b a Emergency Medicine, Department of Critical Care Medicine and Surgery, Careggi University Hospital, Florence, Italy b Department of Cardiology, Careggi University Hospital, Florence, Italy abstract article info Article history: Received 28 August 2012 Received in revised form 25 December 2012 Accepted 26 December 2012 Available online xxxx Background: The link between minor troponin (cardiac troponin I [cTnI]) elevations and atrial fibrillation (AF) is still debated. Methods: A total of 948 patients with AF lasting less than 48 hours participated in the study and were required to undergo 1-month and 12-month follow-up. The exclusion criteria were represented by younger than 18 years, the presence of hemodynamic instability, or severe comorbidity. Primary end point was the composite of ischemic vascular events inclusive of stroke, acute coronary syndrome, revascularization, and death. Results: In the short term, 4 patients (5%) of 78 with abnormal cTnI reached the primary end point (P = .001 vs others). Conversely, in the long term, 13 patients (17%) with abnormal cTnI, 21 (10%) with known ischemic vascular disease, and 50 (5%) aged patients (75 ± 10 years) reached the primary end point (P b .001, P b .001, and P = .002, respectively). At multivariate analysis, abnormal cTnI (hazard ratio [HR], 2.84; 95% confidence interval, 1.38-5.84; P = .005), known ischemic vascular disease (HR, 2.03; 95% confidence interval, 1.11-3.70; P = .021), and age (HR, 1.05; 95 confidence interval, 1.02-1.08; P = .002) were predictors of the primary end point. Minimal or minor cTnI elevation (b 0.45 or ≥ 0.45 ng/mL, respectively) showed no differences when associated with the primary end point. The C-statistic demonstrated the significant prognostic value of older age and known ischemic vascular disease, beyond troponin. Clinical parameters inclusive of heart rate, blood pressure, and risk factors for arteriosclerosis showed no relationship with adverse events. Readmission rate did not differ between groups. Conclusions: In patients with acute AF, minor cTnI elevations link to short-term adverse events. Known ischemic vascular disease and older age showed prognostic value only in the long term. © 2013 Elsevier Inc. All rights reserved. 1. Introduction Abnormal troponin levels have been shown to predict prognosis in acute coronary syndromes and other medical conditions such as sepsis, acute cerebral events, and heart failure, even in seemingly healthy people [1-8]. Moreover, the elevation of troponin I (cardiac troponin I [cTnI]) has been found to be associated with major adverse cardiac events in patients with atrial fibrillation (AF) and is independently related to an increased risk of stroke and mortality [7,9]. Atrial fibrillation is a frequent cause of emergency department (ED) and primary care physician visits, and in recent years, the hospitalizations with AF as a first-listed diagnosis have substantially increased [10,11]. In addition, patients with first diagnosed AF demonstrated to be at high risk for death within the first few months [12]. As a consequence, AF management is a costly public health problem with hospitalizations and short-term adverse cardiovascular events as the primary cost drivers [13-16]. Atrial fibrillation is established to share strong epidemiological associations with a large panel of risk factors and comorbiditiy and may be the effect of underlying “masked” myocardial ischemia [17-19,15]. Thus, the links between known or masked ischemic vascular disease or abnormal cTnI levels and acute AF still need to be discovered. The aim of the present study is to confirm the prognostic value of minor cTnI elevations in patients presenting with recent onset AF (acute AF) and to determine whether any other clinical parameters, comorbidity, or risk factors for arteriosclerosis could link up with outcomes beyond troponin in the short and long term. 2. Patients and methods 2.1. Study population Patients suitable for enrolment were those who presented to the Emergency Department of the Careggi University Hospital, in Florence, Italy, between July 2008 and June 2010. The inclusion American Journal of Emergency Medicine xxx (2013) xxx–xxx ⁎ Corresponding author. E-mail address: aaaconti@hotmail.com (A. Conti). 0735-6757/$ – see front matter © 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.ajem.2012.12.031 Contents lists available at SciVerse ScienceDirect American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem Please cite this article as: Conti A, et al, Abnormal troponin level as short-term predictor of poor outcome in acute atrial fibrillation, Am J Emerg Med (2013), http://dx.doi.org/10.1016/j.ajem.2012.12.031