Understanding stenotic pulmonary arteries: Can computational fluid dynamics help us out?

Abstract

BackgroundAlthough pulmonary artery stenosis is common in congenital heart disease, not much is known about the hemodynamic impact. The effect of stenosis on flow, pressure and wall shear stress can be visualized with computational fluid dynamics. ObjectivesThe aim of this study was to evaluate whether computational fluid dynamics is able to predict flow distribution and pressure gradients in normal and stenotic pulmonary arteries. MethodsThree cases were selected. The cases included one normal anatomy and two geometries representing common patterns in pulmonary artery stenosis. The pulmonary bifurcation was reconstructed using 3D rotational angiography. On the inlet, a patient-specific transient mass flow curve was applied. Full patient-specific outlet boundary conditions were calculated and applied to the outlets of the models. Pressure and flow distribution outcomes were compared to cardiac catheterization and cardiovascular magnetic resonance imaging data respectively. ResultsIn all three cases, the computationally calculated flow distribution was equal to the values measured by magnetic resonance imaging. In one case the pressure in the main pulmonary artery was slightly overestimated by computational fluid dynamics with 7 mmHg. All other pressure outcomes were in complete agreement with the invasive pressure measurements. ConclusionsPressure and flow distribution can be reliably predicted by computational fluid dynamics for normal and stenotic pulmonary arteries. The calculated values of pressure and flow distribution were in excellent agreement with the clinical values. This demonstrates the feasibility and reliability of this method for flow analysis in patients with stenotic pulmonary arteries.