A comparative thrombogenicity study of heparin soaked fluoro-passivated polyester and ePTFE patches in sheep.

Abstract

to compare heparin soaked fluoro-passivated gelatine sealed polyester and expanded polytetrafluoroethylene (ePTFE) patches in a sheep model of acute platelet accumulation following patch angioplasty. heparin soaked patches were placed in the carotid arteries of 9 sheep and autologous (111)Indium labelled platelets were infused. The patches were explanted two hours after the injection of labelled platelets. Median specimen radioactivity was calculated as a ratio of radioactivity in explanted and in 4 ml of blood. Explanted patches were also investigated by scanning electron microscopy (SEM). platelet accumulation was significantly greater on ePTFE patches. For both materials platelet accumulation was greater at the distal end compared to the proximal (p<0.05). SEM demonstrated more platelets as well as thicker thrombus layer on ePTFE-patches. in sheep carotid arteries, a fluoropassivated gelatine sealed polyester patch appears to result in less platelet accumulation when compared to ePTFE.