A new replacement for small vessels

A new modification of the mandril-grown vascular prosthesis appears to combine the best features of presently available synthetic vascular replacement materials. Glutaraldehyde-tanned polyester mesh-supported conduits (diameters 4, 6, and 8 mm) grown in the subcutaneous tissue of sheep, maintain 100% patency in the aortic, aortoiliac, and common iliac positions of canine recipients for over 2 years. One-millimeter diameter grafts placed in the infrarenal abdominal aorta of rat recipients were patent in 72% for 6-month follow-up periods. The grafts maintained a modicum of antigenicity despite tanning, as evidenced by the slightly elevated hemagglutination (0 to 2 dilutions) titers against sheep red blood cells in ovine graft recipients and the accelerated rejection of the donor strain skin grafts in Fischer rats receiving Brown-Norway conduits. Finally, in a limited clinical study, 21 of 24 femoropopliteal and three of three femoroposterior tibial grafts remained patent in short follow-up periods (2 to 16 months). Two aortocoronary bypass grafts have continued to function in one patient for 19 months. Minimal inflammatory reaction and no aneurysmal degeneration were found in the material studied.