Microarterial grafting into the carotid artery of the rabbit: some considerations concerning species-dependent thrombogenicity.

This study was undertaken to obtain more insight into the performance of microarterial prostheses in an experimental animal that resembles the human thrombogenically more closely than the rat. Therefore, microarterial polyurethane-based (PU) prostheses and polytetrafluoroethylene (PTFE) prostheses were implanted into the carotid artery of the rabbit and were compared with regard to patency and thrombus formation at 1 hour (n = 4), 1 day (n = 4), 2 days (n = 4), 1 week (n = 4), 2 weeks (n = 6), 3 weeks (n = 6) and 6 weeks (n = 6) after implantation. Arterial autografts (n = 22), followed up for 2 weeks after implantation, served as a control for the surgical procedure. All arterial autografts were patent at the time of harvesting. In contrast, although all microarterial prostheses were patent at 1 hour and some were patent at 1 day, 2 days and 1 week, none of them were patent at 2, 3 and 6 weeks. The patent PTFE prostheses showed remarkably less thrombus accumulation on the graft surface when compared to the patent PU prostheses. However, all prostheses had the same amount of thrombus formation at the distal anastomosis.