CE: Swati; JCM/201586; Total nos of Pages: 19; JCM 201586 Risk factors for atrial fibrillation recurrence: a literature review Enrico Vizzardi, Antonio Curnis, Maria G. Latini, Francesca Salghetti, Elena Rocco, Laura Lupi, Riccardo Rovetta, Filippo Quinzani, Ivano Bonadei, Luca Bontempi, Antonio D’Aloia and Livio D. Cas Atrial fibrillation is the most common arrhythmia managed in clinical practice and it is associated with an increased risk of mortality, stroke and peripheral embolism. Unfortunately, the incidence of atrial fibrillation recurrence ranges from 40 to 50%, despite the attempts of electrical cardioversion and the administration of antiarrhythmic drugs. In this review, the literature data about predictors of atrial fibrillation recurrence have been highlighted, with a special regard to clinical, therapeutic, biochemical, ECG and echocardiographic parameters after electrical cardioversion and ablation. Identifying predictors of success in maintaining sinus rhythm after cardioversion or ablation may allow a better selection of patients who will undergo these procedures. The aim is to reduce healthcare costs and avoid exposing patients to unnecessary procedures and related complications. Recurrent atrial fibrillation depends on a combination of several parameters and each patient should be individually assessed for such a risk of recurrence. J Cardiovasc Med 2012, 13:000–000 Keyword: atrial fibrillation recurrences, risk factors for recurrence, predictor to maintain sinus rhythm Department of experimental and applied medicine, University of Brescia, Brescia, Italy Correspondence to Dott. Enrico Vizzardi, Piazzale Spedali Civili 1, Brescia 25100, Italy Tel: +39 030 3995659; fax: +39 030 3995061; e-mail: enrico.vizzardi@tin.it Received 12 November 2011 Revised 7 June 2012 Accepted 19 July 2012 Introduction Atrial fibrillation is the most common arrhythmia managed in clinical practice and its incidence increases sharply with age. 1 Atrial fibrillation accounts for one third of all patients discharged with arrhythmia as principal diagnosis. This condition affects 6% of people over 65 years of age, and 10% of those over 80 years. Its prevalence is expected to double in the next 50 years as a consequence of prolongation of life. 2 Atrial fibrilla- tion is associated with an increased risk of mortality, stroke and peripheral embolism. 3,4 At an early stage, atrial fibrillation determines an electrophysiological, mechanical and structural atrial remodeling by shortening, mismatching and lengthening the atrial effective refractory periods (ERPs) (increase of dispersion) and by the depression of intra-arterial conduction and the loss of contractile function. 5 The electrical, mechanical and structural remodeling determines the perpetuation of atrial fibrillation and the progression from paroxysmal to persistent and permanent forms (Fig. 1). Recently, clinical correlations of atrial fibrillation progression were investigated in a large population 6 and these were the findings: 15% of the patients who were included in this study with paroxysmal atrial fibrillation (PAF) progressed to persistent or per- manent atrial fibrillation after 1 year of follow-up. Nearly 50% of the patients with a HATCH score [hypertension – age (75 years and older) – transient ischemic attack or stroke (2 points) – chronic obstructive pulmonary disease – heart failure (2 points)] more than 5 progressed to persistent atrial fibrillation, compared with only 6% of the patients with a HATCH score of 0. This scoring system allows an instant classification of the risk of progression to persistent or permanent atrial fibrillation in patients with PAF. During follow-up, patients with atrial fibrillation progression had been hospitalized more often and had more major adverse cardiovascular events. Several studies investigating atrial fibrillation progression were published in the past. 7–9 The rate of atrial fibrillation progression described in these studies varied between 8 10 and 22% 11 after 1 year of follow-up, depend- ing on the methods used for rhythm-monitoring. Electrical remodeling Atrial electrical remodeling usually appears after 24–48 h from atrial fibrillation debut and results in an increasing and progressive susceptibility to new episodes. The functional and structural atrial changes, which appear after the onset of atrial fibrillation, favor its perpetuation (‘atrial fibrillation begets atrial fibrillation’). 12 Which means that regardless of the presence or absence of ‘triggers’, atrial fibrillation will tend to perpetuate itself thanks to the decisive contribution of the anatomic substrate of atrial myocardium. During the first 48 h from atrial fibrillation onset, electrophysiological processes take place at cellular level, with important consequences. 12 Atrial fibrillation represents a cell stress Systematic review 1558-2027 ß 2012 Italian Federation of Cardiology DOI:10.2459/JCM.0b013e328358554b