Abstract
Atherosclerosis is one of the leading causes of death worldwide. It is a chronic inflammatory disease of the arterial wall that progressively reduces the lumen size because of plaque formation. To understand this pathological process, several hemodynamic studies have been carried out, either experimentally or numerically. However, experimental studies have played an important role to validate numerical results. Recent advances in computer-aided design (CAD), medical imaging, and 3D printing technologies have provided a rapid and cost-efficient method to produce physical biomodels for flow visualization. As a manufacturing process, 3D printing techniques have attracted significant attention due to the low cost and potential to rapidly fabricate biomodels to perform flow hemodynamic studies.
In the present work, a study was performed using biomodels manufactured by 3D printing that mimic both healthy and stenotic coronary arteries with different degrees of stenosis (0%, 50% and 70%). Firstly, it was evaluated the influence of the printing resolution on flow visualization, and the results showed that, when comparing to 150 μm, the 100 μm resolution biomodel was the most adequate for performing the proposed experimental studies, presenting an arithmetic average roughness of 7.24 μm. Secondly, the effect of stenosis severity on velocity and flow behavior was studied. It was concluded that as the severity of stenosis increases, the velocity at the stenosis throat also increases. In addition to this, it was also observed a recirculation zone downstream the stenosis, when the diameter was reduced to 70%.