Method for coating titanium vascular stents, artificial heart valves and other medical devices

Background

An innovative method for surface treatment of titanium vascular stents and other blood connecting devices has been developed. Method includes nanostructuring the surface of vascular stent by electrochemical anodization and subjecting the nanostructured surface to neutral oxygen atoms to eliminate surface induced thrombotic reactions. The developed method reduces adhesion and activation of platelets on medical devices.

Description of invention

The major cause of mortality in the modern world is coronary artery disease. Most percutaneous coronary interventions involve the use of stents, which are implanted to enlarge the vessel lumen, restore blood flow through the affected artery, and thereby reduce the risk of heart attack. Platelet clumping or aggregation in the blood leads to the formation of a thrombus, which further increases this risk.The success of titanium and titanium alloy stents depends primarily on preventing platelet aggregation within blood vessels. This problem can be addressed by nanostructuring the stent surface and subsequently exposing it to plasma in order to eliminate surface-induced thrombotic reactions. The proposed method provides effective surface conditioning, which significantly reduces platelet adhesion and activation.In particular, the method consists of two steps: first, nanostructuring the titanium surface by electrochemical anodization, and second, exposing the nanostructured surface to neutral oxygen atoms to suppress surface-induced thrombotic reactions. The effects of surface structuring on stent performance were clearly observed. Platelets interacted differently with surfaces depending on the treatment of the tested samples. The method was validated by incubating the samples with blood. Distinct differences in platelet adhesion were observed—on surfaces prepared with this method, practically no platelets were present. According to SEM analysis, platelet adhesion was effectively prevented.

Main advantages

• Method of surface structuring prevents adhesion and activation of platelets

• The surface is free of impurities

• Nanostructured surfaces have appropriate chemical structure and topography which reduces the risk of thrombosis on blood contacting devices.