IN-VIVO MORPHOLOGY OF WOVEN, COLLAGEN-SEALED DACRON PROSTHESES IN THETHORACIC AORTA

Background. Long-term changes in knitted Dacron grafts inserted into t he infrarenal aorta have been addressed by a number of studies indicat ing their potential for postoperative dilatation. In contrast, the beh avior of woven, collagen-presealed, double-velour Dacron grafts used t o replace the thoracic aorta is not known. Methods. Forty-five patient s were examined at a mean of 32.4 +/- 14.8 months after insertion of w oven, collagen-coated, Dacron double-velour prostheses (Meadox woven w ith Hemashield, Meadox, Oakland, NJ) in the thoracic position under hi ghly standardized conditions using spiral computed tomography. Results . Compared with a manufactured diameter of 26 mm, all grafts showed an increase of 1 to 5 mm (mean, 3.0 +/- 1.2 mm [11.6% +/- 4.4%]; p < 0.0 001) with greater enlargement of the ascending than of the descending aortic portions (p = not significant). A further statistically signifi cant progressive dilatation failed to occur. Degenerative changes, inc luding false aneurysm formation, could be excluded. Conclusions. Woven , collagen-coated Dacron prostheses are considered a safe replacement material for the thoracic aorta. (C) 1997 by The Society of Thoracic S urgeons.