Numerical Study of the Flow over a Ventricle Assist Device Impeller

Mechanical circulatory support devices have improved the management, survival and prognosis of many patients with Acute or Chronic Heart Failure. However, there is still a high mortality and a wide burden of disease, mostly due to related thrombosis and embolization, thus requiring anticoagulation. Most of the current approved ventricle assist devices (VADs) operate far beyond the critical threshold for biological damage which increases those disease. The need for VADs that minimized blood damage is critical. In this study we examine the effect of impeller design on functionally and hemodynamic using numerical models. Steady and transient numerical simulations of rotating frame using ANSYS CFX were developed, analyzed and validated by experimental system. The simulations utilized to estimate the shear stress, regions of stasis and global pump performance such as flow rate, pressure head and power. The results imply that the numerical models have potential in predicting both hemodynamic and thromboembolism characteristics. Understanding the impact of the geometry on the pump performances and blood damage provide the ability to optimize VADs design.