Experimental studies of the porosity of the alloplastic vein replacement

The vena cava inferior was replaced by alloplastic vein replacement materials in 60 beagle dogs divided in 6 groups. The wall-porosity varied from 50 to 280 ml/cm2 per minute in the textile prostheses (water porosity) (Groups 1-3), and from 30 to 60 micron fibril length in the expanded PTFE-prostheses. All textile prostheses (woven or knitted) are clearly inferior of expanded PTFE-prostheses. The fibril length of 60 micron represents an improvement in comparison with a length of 30 micron regarding the patency rate and the incorporation process, but it needs a special external support.