Is inflammation a risk factor for recurrent atrial fibrillation?

Abstract

Atrial fibrillation (AF) poses an important problem in clinical practice. Restoration and maintenance of sinus rhythm (i.e. secondary prevention of AF) is difficult to achieve.1 This has led to the fact that acceptance of AF in combination with adequate rate control has become a satisfactory alternative in the management of AF. However, the economic burden due to AF remains high, and morbidity and mortality in patients with AF are still substantial. It would thus seem logical to find methods to prevent AF to ever develop (i.e. primary prevention of AF), and consequently, patients at risk of developing AF must be identified to be able to implement preventative strategies. Well-known predictors of AF include age, hypertension, valvular disease, myocardial infarction, diabetes mellitus, and congestive heart failure.2 There are, however, patients with AF with no known underlying disease, classified as ‘lone AF’. The question remains whether lone AF in fact is truly lone, and whether there are other risk factors involved in AF. Less well-known risk factors for AF have increasingly been coming to attention, including sleep apnoea, alcohol or other intoxication abuse, excessive physical activity, latent hypertension (i.e. diastolic dysfunction), genetic factors, obesity or body mass index (BMI), and inflammation.3 Inflammation has been linked to a variety of cardiovascular conditions, including coronary artery disease, diabetes mellitus, and hypertension, and the association between inflammation and AF is increasingly being substantiated.4,5 The exact mechanism relating inflammation with AF is still unknown, and it is also unclear whether inflammation is an initiator or rather a consequence of AF. The existence of post-operative AF would suggest that inflammation precedes AF, as surgery causes a strong inflammatory process which involves complement activation and release of pro-inflammatory cytokines. Indeed, it has been reported that markers of inflammation post-operatively are associated with … *Corresponding author. Tel: +31 50 361 1327, Fax: +31 50 361 4391, Email: i.c.van.gelder{at}thorax.umcg.nl