LAUSR

BACKGROUND Recent research findings revealed key role for oxidative DNA damage in the pathogenesis of atrial fibrillation (AF). Therefore, a circulating oxidative DNA damage marker 8-hydroxy-2'-deoxyguanosine (8-OHdG) may represent a biomarker to stage AF and identify patients at risk for AF recurrence and POAF after treatment. OBJECTIVES To investigate whether serum levels of 8-OHdG correlate with the stage of AF, recurrence after AF treatment and onset of post-operative AF (POAF) after cardiac surgery. METHODS In this prospective and observational study, 8-OHdG levels are detected by ELISA in human serum samples. Blood samples were collected from control patients without AF history, paroxysmal AF and persistent AF patients undergoing electrical cardioversion (ECV) or pulmonary vein isolation (PVI), and sinus rhythm (SR) patients undergoing cardiac surgery. AF recurrence was determined during 12 months follow-up. Univariate and multivariate analysis were used to identify changes in 8-OHdG levels between the groups. RESULTS Compared to the control group, 8-OHdG levels gradually and significantly increased during progression of this arrhythmia. Also 8-OHdG levels in AF patients showing an AF recurrence after PVI treatment were significantly increased compared to patients without AF recurrence. Moreover, in SR patients undergoing cardiac surgery, 8-OHdG levels were significantly elevated in patients showing POAF compared to patients without POAF. CONCLUSIONS The level of 8-OHdG may represent a potential diagnostic biomarker for AF staging, as well as prediction of AF recurrence and POAF after treatment.