Reactive Oxygen Species Following Aortic Valve Replacement

Surgical aortic valve replacement (SVAR) is currently the 'Gold Standard' therapy for patients with severe symptomatic aortic stenosis (AS). Approximately 30-50% of patients with severe AS are deemed inoperable due to comorbidities such as severe respiratory disease, chronic renal disease and peripheral vascular disease. Transcatheter aortic valve replacement (TAVR) has emerged as a novel therapeutic modality for inoperable patients and an effective alternative to SAVR in selected high and intermediate-risk patients. Myocardial ischemia and reperfusion injury (MRI), mediated by reactive oxygen species (ROS), related to cardiopulmonary bypass has been linked to adverse clinical outcomes following cardiac surgery. In contrast to SAVR, transcatheter deployment of aortic prostheses requires shorter time of ischemia and hypotension and may be associated with less ROS mediated MRI. Inflammatory responses and reperfusion injury following TAVR have not been previously described nor compared to SAVR. The aim of this study is therefore to compare the oxidative stress response in patients with isolated severe symptomatic AS undergoing SAVR or TAVR and determine whether it correlates with clinical outcomes.