Heart failure remains a leading cause of mortality worldwide, with limited heart donors making Left Ventricular Assist Devices (LVADs) a critical alternative for patients with end-stage heart failure. However, current LVADs pose challenges for patients with smaller body sizes, particularly children. This study evaluates the hemodynamic performance and thrombosis potential of a smaller impeller LVAD using Computational Fluid Dynamics (CFD). A 37 mm diameter, seven-blade impeller was analyzed across rotational speeds of 2000, 2500, and 3000 rpm, and flow rates ranging from 3 to 7 L/min. Validation against experimental data confirmed the model’s accuracy, with pressure differences closely matching the expected flow profile. Results indicated that high shear regions, particularly at rotational speeds of 2500 and 3000 rpm, affected 34.58–47.26% of surfaces, posing a substantial risk for platelet activation. Conversely, low shear rate regions, though minimal, with a maximum of 0.14% of surfaces experiencing shear rates below 54 s⁻1, were concentrated on the suction side of the impeller blades, presenting a potential risk for stagnation and thrombus formation. While a smaller device size has the potential to improve hemodynamics by reducing areas of stagnation, it also poses a heightened risk of platelet activation due to increased shear in key areas.