Seeding endothelium onto canine arterial prostheses. The effects of graft design

To identify prosthetic characteristics that support the proliferation of an endothelial lining, 14 different graft designs were studied in dogs. The grafts were prepared by the use of a technique of endothelial seeding that we described previously. They were studied two and four weeks after their implantation. Weft-knit Dacron grafts (water porosity from 1,400 to 1,650 mL/min/sq cm) were the most successful. A velour index (velour stitch frequency times velour loop height) was computed. When the internal velour index (IVI) was greater than 60,000 loop-mu/sq cm, the percentage of clot-free surface was 17.2 +/- 14.5%, compared with 62.0 +/- 26.9% when the IVI less than 60,000 loop-mu/sq cm. Endothelium could be detected on 61.5% of the grafts when the IVI less than 60,00 loop-mu/sq cm, compared with 0% when the IVI greater than 60,000 loop-mu/sq cm. The cells that formed the outer capsule were better organized and more adherent to the graft when an external velour was present, but external velour did not affect the inner lining. We conclude that weft-knit Dacron grafts with water porosities from 1,400 to 1,650 mL/min/sq cm and with limited internal velour (IVI less than 60,000 loop-mu/sq cm) are suitable substrates for single-staged endothelial-cell seeding.