Comparative hemocompatibility assessment of fibrin/heparin-coated and PMEA-coated flow diverters

Flow diverters play an important role in the endovascular treatment of intracranial aneurysms; however, their use can be associated with thromboembolic complications. Thus, in recent years, flow diverters with surface coatings have been developed to prevent thrombus-related complications. In this study, the hemocompatibility of the flow diverters FRED X with poly(2-methoxyethyl acrylate) (PMEA) coating and the DERIVO 2heal with fibrin/heparin coating, as well as the uncoated DERIVO 2 flow diverter, was evaluated using an in vitro blood circulation model. Using enzyme-linked immunosorbent assay (ELISA), biomarkers of thrombocytes (β-thromboglobulin (β-TG)), coagulation (thrombin-antithrombin complex (TAT)), complement system (SC5b-9), and inflammation (PMN elastase) activation were analyzed. Further analyses comprised thrombogenicity assessment by scanning electron microscopy and measurement of blood cell counts and hemolysis. The uncoated DERIVO 2 flow diverter exhibited increased coagulation and platelet activation, accompanied by enhanced adhesion of platelets to the blood-contacting surfaces. In contrast, both the FRED X and the DERIVO 2-heal flow diverter could effectively reduce the coagulation (TAT) and platelet activation (β-TG) and prevent the adhesion of platelets. Notably, DERIVO 2heal flow diverter induced significantly lower activation of the complement system (SC5b-9) and reduced inflammatory response (PMN elastase) compared to FRED X flow diverter. These findings indicate the improved hemocompatibility of the fibrin/heparin-coated DERIVO 2heal flow diverter and its potential to reduce thromboinflammatory complications.