Background: Oxidative stress is associated with atrial fibrillation (AF). However, little is known about the relationship between serum markers of oxidation and electrical activity in patients with AF.
Objective: The purpose of this study was to investigate the possible association between serum markers of reactive oxidative metabolism and atrial remodeling in paroxysmal and persistent AF.
Methods: Derivatives of reactive oxidative metabolites (DROM), an index of oxidative stress, were measured in 306 consecutive patients with AF (225 paroxysmal, 81 persistent) undergoing radiofrequency (RF) catheter ablation. Filtered P-wave duration by P-wave signal-averaged ECG and levels of high-sensitivity C-reactive protein (CRP) as an inflammatory marker also were measured.
Results: Patients were followed up for 1.2 +/- 0.8 years. DROM levels in patients with persistent AF were significantly higher than in patients with paroxysmal AF (341.6 +/- 85.5 Carratelli [Carr] units vs 305.0 +/- 77.7 Carr units, P <.001). DROM levels showed a tighter, positive correlation with filtered P-wave duration in persistent AF patients (r = 0.56, P <.001) than in all AF patients (r = 0.13, P <.05). DROM levels also showed a weaker but significant correlation with high-sensitivity CRP in patients with AF. Kaplan-Meier analysis revealed that the highest quartile of basal DROM levels exhibited a significantly higher AF recurrence rate after RF catheter ablation in patients with paroxysmal AF (P <.01).
Conclusion: Serum markers of oxidative stress reflect atrial conduction disturbance and predict AF recurrence after RF catheter ablation in paroxysmal AF patients. DROM could serve as a biomarker for predicting risk of AF recurrence after RF catheter ablation.