Abstract 17526: The Role of Endothelial Function on Paroxysmal and Chronic Atrial Fibrillation

Abstract

Introduction: Atrial fibrillation (AF) is associated with various cardiovascular diseases. Endothelial dysfunction is well validated as a strong predictor of adverse cardiovascular outcomes. Hypothesis: We hypothesized that endothelial dysfunction affects the development and progression of AF. Methods: We enrolled 152 consecutive subjects with AF. Thirty five subjects had paroxysmal AF and 117 chronic (long standing persistent or permanent) AF. Endothelial function was evaluated by flow mediated dilation (FMD). All subjects underwent two-dimensional echocardiographic assessment. Left ventricle ejection fraction (LVEF) was calculated based on biplane method of discs, left ventricle mass index to body surface area (LVmass/BSA) was calculated with the method of Devereux, left atrial diameter index to body surface area (LAdiam/BSA) was measured from the parasternal window and left atrial volume index to body surface area (LAvol/BSA) was measured based on biplane Simpson’s rule. Results: Subjects with chronic AF compared to subjects with paroxysmal AF were older (73±10 years vs. 66±15 years, p=0.002), had impaired LVEF (44±14% vs. 53±9%, p=0.001) increased LAdiam/BSA (26±4mm/m2 vs. 20±3mm/m2, p<0.001), increased LAvol/BSA (41±9.6ml/m2 vs. 29±7.7ml/m2, p<0.001), increased LVmass/BSA (116±35 gr/m2 vs. 99±29 gr/m2, p=0.06) and impaired creatinine clearance (64±18 ml/min/1.73m2 vs. 83±20 ml/min/1.73m2, p=0.001). Importantly, subjects with chronic AF had impaired FMD compared to subjects with paroxysmal AF (4.09±1.67% vs. 6.83±1.38% p<0.001). In addition, there was an inverse correlation between FMD and LAdiam/BSA (r=-0.53, p<0.001), LAvol/BSA (r=-48, p<0.001), LVmass/BSA (r=-0.364, p=0.007) and a positive correlation between FMD and LVEF (rho=0.30, p=0.003). Interestingly, a linear regression model revealed that subjects with chronic AF had impaired FMD [b=-1.61 95%CI(-2.33 to -0.89), p<0.001] even after adjustment for confounders such as age, sex, LVEF, LVmass/BSA, LAvol/BSA, creatinine clearance, arterial hypertension and the presence of diabetes mellitus. Conclusions: Endothelial dysfunction is associated with atrial remodeling in patients with AF and is implicated in the progression from paroxysmal to chronic AF.