Effects of the atrium on intraventricular flow patterns during mechanical circulatory support.

Simulations of the ventricular flow patterns during left ventricular assist device (LVAD) support are mainly performed with idealized cylindrical inflow, neglecting the influence of the atrial vortex. In this study, the influence of the left atrium (LA) on the intra-ventricular flow was investigated via Computational Fluid Dynamics (CFD) simulations. Ventricular flow was simulated by a combined Eulerian (carrier flow)/Lagrangian (particles) approach taking into account either the LA or a cylindrical inflow section to mimic a fully support condition.

Effect of Timings of the Lavare Cycle on the Ventricular Washout in an In Vitro Flow Visualization Setup.

Left ventricular assist devices inherently alter the intraventricular flow field and create areas of blood stasis with potential thrombus formation. The Lavare cycle of the Medtronic HeartWare HVAD was designed to improve ventricular washout. This study aims to evaluate its effects on ventricular washout in a pulsatile in vitro setting with a focus on the timing of pump speed changes.

The influence of left ventricular assist device inflow cannula position on thrombosis risk.

The use of left ventricular assist devices (LVADs) as a treatment method for heart failure patients has been steadily increasing; however, pathological studies showed presence of thrombi around the HeartWare ventricular assist device inflow cannula (IC) in more than 95% of patients after device explantation. Flow fields around the IC might trigger thrombus formation and require further investigation. In this study flow dynamics parameters were evaluated for different patient geometries using computational fluid dynamics (CFD) simulations.

Validation of numerically simulated ventricular flow patterns during left ventricular assist device support.

Intraventricular flow patterns during left ventricular assist device support have been investigated via computational fluid dynamics by several groups. Based on such simulations, specific parameters for thrombus formation risk analysis have been developed. However, computational fluid dynamic simulations of complex flow configurations require proper validation by experiments.