The influence of arterial stenosis on blood damage under continuous flow

Arterial stenosis, resulting from plaque accumulation, can lead to serious conditions such as thrombosis and von Willebrand syndrome. This study investigates how variations in stenosis shape and severity affect red blood cell (RBC) and von Willebrand factor (VWF) damage through simulations and experimental approaches. A continuous flow generation device was utilized to create a blood circulation platform. The effects of different stenosis shapes and severities under continuous flow conditions on RBC damage and VWF degradation were examined. Blood samples were then analyzed for plasma-free hemoglobin concentration and VWF degradation. The results indicated that increased stenosis severity correlated with elevated hemolysis and a higher degradation rate of high molecular weight VWF (HMW-VWF). Rectangular stenosis induced more severe hemolysis and VWF degradation compared to elliptical stenosis at equivalent stenosis degrees. Both stenosis types demonstrated varying VWF degradation rates at low and medium/high stenosis levels, with elliptical stenosis showing particularly low VWF degradation at lower stenosis levels. The study highlights that different stenosis shapes and severities significantly affect blood damage under continuous flow. Greater stenosis severity resulted in increased blood flow velocity and wall shear stress (WSS), leading to enhanced hemolysis and VWF degradation, with rectangular stenosis showing more pronounced effects.