In vitro endothelialization of a mesosystemic shunt: a clinical case report

The existence of a confluently covering endothelium that is free of any thrombotic appositions can be proved 30 days after clinical implantation of an in vitro endothelialized expanded polytetrafluoroethylene graft. The recipient of the mesosystemic H-graft was a 69-year-old man who had a thrombosed portal vein following pancreatitis. Autologous endothelial cells were obtained from the external jugular vein under local anesthesia, applying the in situ cannulation technique. After low-density plating, first-passage mass cultures of 1.22 x 10(6) endothelial cells were obtained 14 days after vein excision. After precoating was accomplished with fibrinolytically inhibited fibrin glue, a 10 mm expanded polytetrafluoroethylene graft was confluently lined with the autologous endothelial cells at a seeding density of 1.2 x 10(5) cells/cm2. After a maturation period of an additional 9 days and the microbiologic exclusion of a possible infection, an 11 cm graft segment was implanted between the superior mesenteric vein and the inferior vena cava. In spite of a patent shunt the patient had a repeat bleeding episode, needed parenteral nutrition, and died of sepsis on day 30. Immediately after the graft had been taken out, specimens were processed by scanning electron microscopy and light microscopy for the immunohistochemical proof of the endothelial nature of the surface-covering cell layer. The entire graft surface displayed a confluent cell lining that was free of any thrombotic appositions. A strongly positive stain result for both factor VIII-related antigen and the fixation-resistant CD34 molecule identified these cells as endothelial. No alpha-actin-positive cells could be detected. The underlying protein matrix was well preserved and unaltered in thickness and appearance, compared with preimplantation samples. None of the specimens showed any evidence of infection. This human demonstration of an intact endothelium on a patent venous prosthesis further establishes in vitro lining as a method that actually creates a persistent and functioning endothelium on a synthetic graft surface.