Finite element analysis of blood flow via a shunt from the left ventricle to the distal segment of a stenosed coronary artery

New methods are currently being developed that provide a direct connection between the left ventricle and the distal portion of an obstructed coronary artery. Optimal design of such a device can be aided by the use of numerical analysis. Here, computational results are presented showing the hemodynamic flows through a bypass shunt providing flow to a stenosed coronary artery. A PISO type finite element method is used to solve the three-dimensional incompressible Navier-Stokes equations for flow passing through a bypass shunt into the occluded coronary artery. Time-varying inlet flow from the left ventricle is obtained from a simulation of the entire coronary and systemic circulations. The main objective of this study is to delineate the influence of shunt angle on detailed flow patterns. Three different shunt angles are examined. Computational results show a recirculating region generated near the junction of the coronary artery with the bypass shunt. Secondary flow is induced in the cross-sectional plane perpendicular to the axis of the artery and is progressively attenuated downstream. Among the three cases studied, secondary flows are greatest with the 90° shunt angle. The maximum pressure drop between inlet to outlet also increases with increasing shunt angle