Haemodynamic aspects of lower limb arterial reconstruction using Dacron and Goretex prostheses.

We have studied some haemodynamic consequences of vascular grafts of less than 8 mm diameter by animal studies on dogs before and after aortofemoral bypass with either knitted Dacron 5 mm internal diameter (6 dogs) or Goretex 6 mm internal diameter (7 dogs) prostheses between 17 and 24 cm in length. Both materials gave an increased velocity of pulse wave transmission for pressure and flow and an increase in resistance to pulsatile flow. The effects were more severe with Dacron than with Goretex. Pressure index and pressure pulsatility were not significantly altered, but flow pulsatility index, peak flow rate, and peak flow acceleration were all significantly reduced after both implants. These results are due to mismatching of mechanical properties leading to an increased impedance to pulsatile flow.