Evaluation of a clinically useful length of 1 mm diameter PTFE as a microvascular graft.

Previous studies of 1 mm internal diameter polytetrafluoroethylene (PTFE) have investigated short graft lengths. The aim of this experiment was to assess a longer, clinically useful graft. Femoro-femoral crossover grafts 6 cm long were implanted into 20 rats and, after an initial observation period of 1 hour, were followed up for four weeks. Ten grafts failed within the first hour post-operatively, one was occluded at 2 weeks and nine were patent at 4 weeks (45% patency). Technical errors causing stasis within the prosthesis led to the early failures. When stasis was avoided patency was good and did not appear to be dependent upon development of a cellular lining within the graft.