Research on the Influence of Microstructured Surface Characterization Parameters on Blood Damage.

Background: Mechanical circulatory support devices (MCSDs) are among the most effective treatments of end-stage heart failure. Despite their efficacy, patients often experience hemocompatibility issues such as hemolysis and gastrointestinal bleeding caused by blood damage. The surface characteristics of blood-contacting materials significantly affect hemocompatibility, and designing specific surface microstructures may help mitigate blood damage.

Methods: In this study, microstructures with various morphologies were designed and fabricated on silicon wafer surfaces, and an in vitro blood circulation platform was involved to conduct blood-shearing experiments on these modified surfaces. The sheared blood samples were analyzed for free hemoglobin concentration and high molecular weight von Willebrand Factor (HMW-VWF) degradation.

Results: The results demonstrated that microcylindrical structures with higher aspect ratios could simultaneously reduce both hemolysis and HMW-VWF degradation. While microcylindrical structures outperformed micrograting structures in reducing hemolysis, both of them performed similarly regarding VWF damage. The results highlight that variations in the morphological parameters of the microstructure significantly influence hemolysis and HMW-VWF degradation. Specifically, different aspect ratios and structural designs affect how blood interacts with the surface, altering the extent of blood component damage.

Conclusions: These findings suggest that tailoring surface microstructures could enhance the hemocompatibility of blood-contacting materials in MCSDs, offering valuable insights for their design and optimization.