Abstract 5865: The Role of Inflammation and Oxidative Stress in Atrial Fibrillation
Background: There is increasing evidence that inflammation and oxidative stress contribute to the pathogenesis of atrial fibrillation (AF), but their role remains poorly defined. Furthermore, it is unclear whether inflammation and oxidative stress are associated with different types of AF. The purpose of this study was to define the role of inflammation and oxidative stress in patients with AF.
Methods: We studied 305 patients with AF enrolled in Vanderbilt AF registry, a clinical and genetic database, and 105 controls. AF was categorized into lone AF (≤65 yrs with no overt structural heart disease) and typical AF, and further subcategorized as paroxysmal, persistent or permanent AF. A panel of serum inflammatory and cytokine biomarkers, and urinary F2-isoprostanes, a sensitive index of oxidative stress in vivo, were measured in patients with AF and controls.
Results: Serum interleukin (IL)-1β, IL-6, IL-8, IL-10, tumor necrosis factor (TNF)α, vascular endothelial growth factor (VEGF), and N-terminal pro-brain natriuretic peptide (NT-ProBNP) were independently associated with AF (all P<0.05), but urinary F2 isoprostanes were not elevated (P=0.40). There were no differences in inflammatory biomarkers, F2-isoprostanes, and NT-ProBNP between lone and typical AF after adjustment for age, race, sex, BMI, CHF and statin use. However, there was a graded increase in concentrations of TNF-α (median [IQR]: 6.8 [3.4 –11.3], 8.0 [5.6 –10.9], 10.1 [5.7–12.4] pg/ml, P=0.007) and NT-ProBNP: 170.6 [67.3– 481.8], 681.4 [310.3–1439.0], 1179.9 [653.1–2096.0] pg/ml, P<0.001) across the subgroups of paroxysmal, persistent and permanent AF, respectively after adjustment. Urinary F2-isoprostanes were similar among the different subtypes of AF.
Discussion: Inflammatory biomarkers were significantly increased in both lone and typical AF, providing compelling evidence of a strong association between inflammation and the arrhythmia. However, urinary F2-isoprostanes were not increased in patients with AF suggesting that oxidative stress may not play a prominent role in the etiology of this common and morbid condition.