Background: Over the past 17 years, our group has developed and clinically applied an in vitro endothelialization procedure whereby infrainguinal expanded polytetrafluoroethylene (ePTFE) prostheses are confluently lined with cultured autologous endothelial cells before implantation. After a successful randomized pilot study from 1989 to 1993, the procedure was adopted for routine operations.
Methods: Since June 1993, 153 endothelialized ePTFE grafts were implanted in the infrainguinal position in 136 patients (102 above knee (AK) and 51 below knee (BK), 89 men and 47 women, mean age 64.7+/-9.4 years). Seventeen patients received an endothelialized prosthesis bilaterally. Autologous endothelial cells were harvested from 4- to 5-cm segments of a subcutaneous vein (in 86% the cephalic vein), grown to first-passage mass cultures and confluently lined onto 6- (n = 113) or 7-mm (n = 40) inner diameter (ID) ePTFE grafts, precoated with fibrin glue. The observation period for 6-mm grafts was 7 years, and for 7-mm grafts was 4 years. Patency assessment for Kaplan-Meier survivorship analyses was based on duplex sonography and angiography.
Results: Kaplan-Meier survivorship function revealed a primary patency rate of 62.8% after 7 years (SE = 0.05) for all infrainguinal reconstructions (60% AK/70.8% BK). The primary patency for stage II and III patients was 64.4% after 7 years. The more recent group of 7-mm ID grafts showed a primary patency of 83.7% after 4 years.
Conclusions: Our data provide strong evidence that autologous endothelial cell lining distinctly improves the patency of small diameter vascular grafts.