Abstract 18682: Increased Oxidative Stress is Associated With Vascular Endothelial Dysfunction and Central and Peripheral Arterial Stiffening in Patients With Fontan Circulation

Background: It is well recognized that oxidative stress is responsible for fat accumulation and tissue inflammation, and causes endothelial cell damage that leads to the initiation of atherosclerosis. We and others have previously reported that vascular stiffness is increased with impaired vascular endothelial function in patients after Fontan operation. We hypothesized that increased oxidative stress is associated with vascular endothelial dysfunction and arterial stiffening in patients with Fontan circulation Methods: Relationship of oxidative stress with endothelial function and arterial stiffness was examined in 16 Fontan patients. Endothelial function and arterial stiffness of forearm artery was measured by flow mediated dilatation. We also measured central arterial stiffness by calculating aortic pulse wave velocity (PWV) during catheter drawback from the ascending aorta to the iliac bifurcation at the time of cardiac catheterization. Oxidative stress was estimated by measuring serum levels of oxidized low-density lipoprotein (LDL) and superoxide dismutase (SOD) activity in the urine as an anti-oxidant. Results: PWV of the ascending aorta but not of the descending aorta was significantly and positively correlated with oxidized LDL level (P Conclusion: Increased oxidative stress is associated with vascular endothelial dysfunction and central and peripheral arterial stiffening in patients with Fontan circulation. Antioxidant therapy may improve vascular health and thereby patient’s outcome after Fontan operation.