RESUMO
We evaluated the effect of a selective thromboxane synthetase inhibitor (TSI) on the patency of autogenous vein grafts in dogs. Treatment involved oral dosing (10 mg/kg bid) of TSI or placebo, combined with local treatment of the graft with TSI or placebo (papavarine) at the time of implantation. At harvest, two animals, one from each oral dosing group, had an occluded graft; both grafts had been locally treated with papavarine. We found no significant histopathologic difference between graft treatment groups. Attempts to estimate the effect of TSI dosing on the prostacyclin/thromboxane balance through radioimmunoassay analysis of graft perfusates were unsuccessful. As measured by in vitro platelet aggregation, oral TSI was found to alter platelet function, though not in a dose-dependent fashion, and the animals rebounded toward normal at 12 hours.
