BICOMPONENT VASCULAR GRAFTS CONSISTING OF SYNTHETIC ABSORBABLE FIBERS.1. IN-VITRO STUDY

The objective of this study is to determine the effects of the locatio n and concentration of synthetic absorbable yarn components in bicompo nent vascular graft fabrics on their structure and properties in a con trolled in vitro hydrolytic environment. Bicomponent vascular fabrics were made from Dacron and polyglycolic acid (PGA) yams with a range of composition ratios of PGA to Dacron and a range of locations of PGA. Both woven and single jersey knit fabrics were made. These fabrics wer e characterized by standard textile methods and subject to in vitro hy drolytic degradation study. In vitro hydrolytic degradation study show ed that the most dramatic changes in the bicomponent fabric characteri stics and properties occurred 30 and 60 days of hydrolysis. This sched ule coincided with the hydrolytic degradation rate of PGA absorbable s utures. In the woven (W) group, the incorporation of absorbable yarns in the weft direction (W3) of the bicomponent fabrics resulted in the velour-like, loose, and porous surface morphology of the fabric for po tential subsequent tissue ingrowth, while those woven fabrics with abs orbable yams in the warp direction (W1) did not have this unique velou r-like surface. In the knitted (K) group, the concentration of absorba ble yams appeared to be closely related to the observed changes in fab ric properties and structure. The incorporation of absorbable yams int o knitted fabrics did not result in the same level change in fabric st ructure and property as woven fabrics. In both W and K groups, a minim al level of mechanical strength of the fabrics was maintained due to t he remaining Dacron yams. Structural integrity of these fabrics was re tained at the end of hydrolytic degradation study. The data obtained c ould be used to correlate with the subsequent in vivo performance of t hese bicomponent vascular grafts. If correlations exist, they could be used to improve the design of future bicomponent vascular grafts for improved performance. (C) 1993 John Wiley & Sons, Inc.