[thedoctor79]

I'm not a professional so what I'm saying could be stupid, but I don't see why anti-coagulant medication has to act globally in the organism for something that is a localized issue. I realize the circulatory system is not segmented, however couldn't there be something to be done with the time of action of the anti-coagulant? From my vague recollection, clot formation has something to do with turbulent flow post-valve as well, so improvements might be made in this area as well... try getting a fluid dynamics expert in the team that designs the valves, and I'm not joking. FWIW.