Heart failure is the leading cause of hospitalisation in people over 65. A left ventricular assist device (LVAD) is an option to provide mechanical circulatory support as a ‘bridge to cardiac transplantation’ or ‘destination therapy’. The aim of this project was to assess the effects of different LVAD connection on the blood flow in order to find the optimum cannula connection. The other aim of this work was to assess the effects of LVAD on the severity of heart failure. In this project, a patient specific configuration, obtained by MRI was converted into a computational model and accurate CFD simulations were carried out for different degree of heart failure. This project resulted in important findings about the surgical configuration and the design of LVAD cannulas.