Numerical modeling of pulsatile blood flow in the pulmonary artery under the influence of pulmonary hypertension and concomitant pathologies

This paper presents a numerical simulation of blood flow in a patient-specific pulmonary artery geometry to study the effect of pulmonary hypertension and associated pathologies such as stenosis and aneurysm on hemodynamics. Six models were investigated: healthy artery, artery with pulmonary hypertension, stenosis, aneurysm, pulmonary hypertension with stenosis, and pulmonary hypertension with aneurysm. Pulsatile blood flow was modeled using a physiologically accurate velocity waveform corresponding to normal and hypertensive conditions. The Carreau rheological model was applied to account for the non-Newtonian behavior of blood, with the flow assumed to be laminar and incompressible. The governing Navier-Stokes equations were discretized using the finite volume method. The analysis focused on the evaluation of pressure distributions, velocity profiles, and wall shear stress. The results showed significant differences between normal and pathological conditions, with pulmonary hypertension leading to increased pressure and wall shear stress, especially in areas of stenosis and bifurcations. Aneurysms caused localized decreases in flow velocity, while stenosis led to increases in velocity and wall shear stress.