Surgical aortic valve replacement (SAVR) is the most effective treatment for patients with severe aortic stenosis (AS). However, patient-prosthesis mismatch is prevalent in up to 80% of cases and can lead to left ventricular hypertrophy and diastolic heart failure. Aortic root enlargement (ARE) allows the implantation of larger valves, decreasing pressure gradients while providing a larger annulus for potential future transcatheter AVR (TAVR). However, it has been suggested that ARE may also increase the risk of hemostasis and thrombus formation. To assess the hemodynamic impact of ARE, we performed patient-specific CFD analysis of 4 pairs of matched AS patients. Each pair consists of a patient with AVR+ARE matched with an AVR no ARE patient based on age, sex, ejection fraction, and native annulus size. For each AVR+ARE patient, we virtually deployed a SAV into their pre-operative geometry to act as another control model (virtual AVR no ARE). Hemodynamic parameters, including heart rate and stroke volume, were standardized for all patients to isolate the effects of root anatomy. The 3D model was coupled to 2-element Windkessel models at the coronary arteries and aortic outflow and CFD simulations were performed on the finite-element multiphysics solver Cheart. Transvalvular peak velocities and pressure gradients were calculated, and blood residence time was computed over 5 cardiac cycles. \textit{AVR+ARE} decreased the mean AV pressure gradient by 507% and 542% and decreased the peak velocity by 74% and 56% in the AVR no ARE and virtual AVR no ARE groups respectively. There was less than a 2.7% difference in blood residence time and all models had complete blood washout within 5 cardiac cycles. Hemodynamic simulations of AVR+ARE showed an expected marked reduction in the pressure gradients and peak velocity. Importantly, this came with only a minimal difference in blood stasis in the sinuses, suggesting a limited risk of thrombosis with ARE. Furthermore, the ARE procedure, followed by a simulated valve-in-valve, showed better hemodynamic outcomes over cases without enlargement, highlighting the long-term benefits of ARE.