The predictive value of inflammatory and oxidative markers following the successful cardioversion of persistent lone atrial fibrillation Dionyssios I. Leftheriotis a, ⁎ , Katerina T. Fountoulaki a , Panayota G. Flevari a , John T. Parissis a , Fotis K. Panou a , Ioanna T. Andreadou b , Koula S. Venetsanou c , Efstathios K. Iliodromitis a , Dimitrios Th. Kremastinos a a “Attikon” University Hospital of Athens, Department of Cardiology, Athens, Greece b University of Athens, School of Pharmacy, Department of Pharmaceutical, Chemistry, Athens, Greece c “KAT” General Hospital, Department of Biochemistry, Athens, Greece Received 13 July 2007; received in revised form 6 February 2008; accepted 4 April 2008 Available online 21 July 2008 Abstract Background: Although there is evidence that inflammation and oxidative stress might contribute to the pathogenesis of atrial fibrillation (AF), the predictive value of inflammatory and oxidative stress markers in patients with AF has not been fully assessed. The aim of this study is to evaluate these markers as predictors of sinus rhythm (SR) maintenance, in patients with persistent lone AF. Methods: Among 268 patients with symptomatic AF, we studied 46 patients with a first episode of recently established persistent lone AF. We measured the circulating levels of hs-CRP, TNF-α, IL-6, IL-10, sICAM-1, sVCAM-1, malondialdehyde (MDA) and nitrotyrosine (NT) before, 1 h, 24 h, 1, 2, 4 and 6 weeks after cardioversion. During a 12-month follow-up period, AF recurrence was evaluated by Holter ECG recordings every month and when symptoms were reported. Results: Baseline levels of CRP, TNF-α, sICAM-1, MDA, and NT were elevated in patients with AF compared to controls, and higher in patients with than in those without persistent AF recurrence, while IL-6 levels were equally elevated in the two subgroups. SR maintenance was associated with lower baseline MDA values and faster decrease in IL-6, sICAM-1 and NT levels within the first 2 weeks following SR restoration. Conclusions: Increased markers of inflammation and oxidative stress are found in patients with lone AF, implying that inflammation and oxidative stress may be associated with the presence of the arrhythmia. IL-6, sICAM-1, MDA and NT, assessed prior to and after the first cardioverted episode of persistent arrhythmia, appear to be reliable, early predictors of SR maintenance during the following year. © 2008 Elsevier Ireland Ltd. All rights reserved. Keywords: Atrial fibrillation; Inflammation; Oxidative stress; Prognosis 1. Introduction The prediction of atrial fibrillation (AF) recurrence after a successful cardioversion in patients with lone AF of recent onset is clinically important. Furthermore, it represents a challenge for understanding the nature of AF, in the absence of abnormal structural substrate. Various pathophysiological mechanisms have been implicated in the development of AF [1,2]. There is evidence that inflammation and oxidative stress might contribute to the pathogenesis of the arrhythmia [3–8]. However, most of the reports to date are based on heterogeneous populations with AF of different origin. In these studies, various abnormal cardiac substrates (such as valve disease, heart failure or coronary artery disease) were present, triggering the inflammatory and oxidative mechanisms, and predisposing International Journal of Cardiology 135 (2009) 361 – 369 www.elsevier.com/locate/ijcard ⁎ Corresponding author. 1 Rimini street, Haidari, Athens, 12462, Greece. Tel.: +302105832355; fax: +302105832351. E-mail address: dleftheriotis@yahoo.com (D.I. Leftheriotis). 0167-5273/$ - see front matter © 2008 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ijcard.2008.04.012