Role of inflammation in early atrial fibrillation recurrence

AIMS: Outcome of rhythm control in atrial fibrillation (AF) is still poor due to various mechanisms involved in the initiation and perpetuation of AF. Differences in timing of AF recurrence may depend on different types of mechanisms. The aim of this study was to assess the mechanisms involved in early AF recurrence in patients with short-lasting AF. METHODS AND RESULTS: Patients with short-lasting persistent AF undergoing rhythm control (n= 100) were included. Markers of mechanisms involved in the initiation and perpetuation of AF were assessed, including clinical factors, echocardiographic parameters, and biomarkers. Primary endpoint was early AF recurrence (recurrence <1 month). Secondary endpoint was progression to permanent AF. Median total AF history was short: 4.2 months. Early AF recurrences occurred in 30 patients (30%) after a median of 6 (inter-quartile range 2-14) days. Baseline log(2) interleukin (IL)-6 adjusted hazard ratio (HR) 1.3, 95% confidence interval (CI) 1.0-1.7, P= 0.02 and present or previous smoking (adjusted HR 3.6, 95% CI 1.2-10.9, P= 0.03) were independently associated with early AF recurrence, suggesting that inflammation played an important role in early recurrences. Atrial fibrillation became permanent in 29 patients (29%). Baseline transforming growth factor-β1, left ventricular ejection fraction, and early AF recurrence were independently associated with progression to permanent AF. CONCLUSION: In patients with short-lasting AF, early AF recurrence seemed to be associated with inflammation as represented by IL-6. Treatment aimed against inflammation may therefore prevent early AF recurrences, which can improve rhythm control outcome.